does time travel in speed of light

Why does time change when traveling close to the speed of light? A physicist explains

Assistant Professor of Physics and Astronomy, Rochester Institute of Technology

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Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to [email protected] .

Why does time change when traveling close to the speed of light? – Timothy, age 11, Shoreview, Minnesota

Imagine you’re in a car driving across the country watching the landscape. A tree in the distance gets closer to your car, passes right by you, then moves off again in the distance behind you.

Of course, you know that tree isn’t actually getting up and walking toward or away from you. It’s you in the car who’s moving toward the tree. The tree is moving only in comparison, or relative, to you – that’s what we physicists call relativity . If you had a friend standing by the tree, they would see you moving toward them at the same speed that you see them moving toward you.

In his 1632 book “ Dialogue Concerning the Two Chief World Systems ,” the astronomer Galileo Galilei first described the principle of relativity – the idea that the universe should behave the same way at all times, even if two people experience an event differently because one is moving in respect to the other.

If you are in a car and toss a ball up in the air, the physical laws acting on it, such as the force of gravity, should be the same as the ones acting on an observer watching from the side of the road. However, while you see the ball as moving up and back down, someone on the side of the road will see it moving toward or away from them as well as up and down.

Special relativity and the speed of light

Albert Einstein much later proposed the idea of what’s now known as special relativity to explain some confusing observations that didn’t have an intuitive explanation at the time. Einstein used the work of many physicists and astronomers in the late 1800s to put together his theory in 1905, starting with two key ingredients: the principle of relativity and the strange observation that the speed of light is the same for every observer and nothing can move faster. Everyone measuring the speed of light will get the same result, no matter where they are or how fast they are moving.

Let’s say you’re in the car driving at 60 miles per hour and your friend is standing by the tree. When they throw a ball toward you at a speed of what they perceive to be 60 miles per hour, you might logically think that you would observe your friend and the tree moving toward you at 60 miles per hour and the ball moving toward you at 120 miles per hour. While that’s really close to the correct value, it’s actually slightly wrong.

This discrepancy between what you might expect by adding the two numbers and the true answer grows as one or both of you move closer to the speed of light. If you were traveling in a rocket moving at 75% of the speed of light and your friend throws the ball at the same speed, you would not see the ball moving toward you at 150% of the speed of light. This is because nothing can move faster than light – the ball would still appear to be moving toward you at less than the speed of light. While this all may seem very strange, there is lots of experimental evidence to back up these observations.

Time dilation and the twin paradox

Speed is not the only factor that changes relative to who is making the observation. Another consequence of relativity is the concept of time dilation , whereby people measure different amounts of time passing depending on how fast they move relative to one another.

Each person experiences time normally relative to themselves. But the person moving faster experiences less time passing for them than the person moving slower. It’s only when they reconnect and compare their watches that they realize that one watch says less time has passed while the other says more.

This leads to one of the strangest results of relativity – the twin paradox , which says that if one of a pair of twins makes a trip into space on a high-speed rocket, they will return to Earth to find their twin has aged faster than they have. It’s important to note that time behaves “normally” as perceived by each twin (exactly as you are experiencing time now), even if their measurements disagree.

You might be wondering: If each twin sees themselves as stationary and the other as moving toward them, wouldn’t they each measure the other as aging faster? The answer is no, because they can’t both be older relative to the other twin.

The twin on the spaceship is not only moving at a particular speed where the frame of references stay the same but also accelerating compared with the twin on Earth. Unlike speeds that are relative to the observer, accelerations are absolute. If you step on a scale, the weight you are measuring is actually your acceleration due to gravity. This measurement stays the same regardless of the speed at which the Earth is moving through the solar system, or the solar system is moving through the galaxy or the galaxy through the universe.

Neither twin experiences any strangeness with their watches as one moves closer to the speed of light – they both experience time as normally as you or I do. It’s only when they meet up and compare their observations that they will see a difference – one that is perfectly defined by the mathematics of relativity.

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Is Time Travel Possible?

We all travel in time! We travel one year in time between birthdays, for example. And we are all traveling in time at approximately the same speed: 1 second per second.

We typically experience time at one second per second. Credit: NASA/JPL-Caltech

NASA's space telescopes also give us a way to look back in time. Telescopes help us see stars and galaxies that are very far away . It takes a long time for the light from faraway galaxies to reach us. So, when we look into the sky with a telescope, we are seeing what those stars and galaxies looked like a very long time ago.

However, when we think of the phrase "time travel," we are usually thinking of traveling faster than 1 second per second. That kind of time travel sounds like something you'd only see in movies or science fiction books. Could it be real? Science says yes!

This image from the Hubble Space Telescope shows galaxies that are very far away as they existed a very long time ago. Credit: NASA, ESA and R. Thompson (Univ. Arizona)

How do we know that time travel is possible?

More than 100 years ago, a famous scientist named Albert Einstein came up with an idea about how time works. He called it relativity. This theory says that time and space are linked together. Einstein also said our universe has a speed limit: nothing can travel faster than the speed of light (186,000 miles per second).

Einstein's theory of relativity says that space and time are linked together. Credit: NASA/JPL-Caltech

What does this mean for time travel? Well, according to this theory, the faster you travel, the slower you experience time. Scientists have done some experiments to show that this is true.

For example, there was an experiment that used two clocks set to the exact same time. One clock stayed on Earth, while the other flew in an airplane (going in the same direction Earth rotates).

After the airplane flew around the world, scientists compared the two clocks. The clock on the fast-moving airplane was slightly behind the clock on the ground. So, the clock on the airplane was traveling slightly slower in time than 1 second per second.

Credit: NASA/JPL-Caltech

Can we use time travel in everyday life?

We can't use a time machine to travel hundreds of years into the past or future. That kind of time travel only happens in books and movies. But the math of time travel does affect the things we use every day.

For example, we use GPS satellites to help us figure out how to get to new places. (Check out our video about how GPS satellites work .) NASA scientists also use a high-accuracy version of GPS to keep track of where satellites are in space. But did you know that GPS relies on time-travel calculations to help you get around town?

GPS satellites orbit around Earth very quickly at about 8,700 miles (14,000 kilometers) per hour. This slows down GPS satellite clocks by a small fraction of a second (similar to the airplane example above).

GPS satellites orbit around Earth at about 8,700 miles (14,000 kilometers) per hour. Credit: GPS.gov

However, the satellites are also orbiting Earth about 12,550 miles (20,200 km) above the surface. This actually speeds up GPS satellite clocks by a slighter larger fraction of a second.

Here's how: Einstein's theory also says that gravity curves space and time, causing the passage of time to slow down. High up where the satellites orbit, Earth's gravity is much weaker. This causes the clocks on GPS satellites to run faster than clocks on the ground.

The combined result is that the clocks on GPS satellites experience time at a rate slightly faster than 1 second per second. Luckily, scientists can use math to correct these differences in time.

If scientists didn't correct the GPS clocks, there would be big problems. GPS satellites wouldn't be able to correctly calculate their position or yours. The errors would add up to a few miles each day, which is a big deal. GPS maps might think your home is nowhere near where it actually is!

In Summary:

Yes, time travel is indeed a real thing. But it's not quite what you've probably seen in the movies. Under certain conditions, it is possible to experience time passing at a different rate than 1 second per second. And there are important reasons why we need to understand this real-world form of time travel.

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Would you really age more slowly on a spaceship at close to light speed?

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Every week, the readers of our space newsletter, The Airlock , send in their questions for space reporter Neel V. Patel to answer. This week: time dilation during space travel. 

I heard that time dilation affects high-speed space travel and I am wondering the magnitude of that affect. If we were to launch a round-trip flight to a nearby exoplanet—let's say 10 or 50 light-years away––how would that affect time for humans on the spaceship versus humans on Earth? When the space travelers came back, will they be much younger or older relative to people who stayed on Earth? —Serge

Time dilation is a concept that pops up in lots of sci-fi, including Orson Scott Card’s Ender’s Game , where one character ages only eight years in space while 50 years pass on Earth. This is precisely the scenario outlined in the famous thought experiment the Twin Paradox : an astronaut with an identical twin at mission control makes a journey into space on a high-speed rocket and returns home to find that the twin has aged faster.

Time dilation goes back to Einstein’s theory of special relativity, which teaches us that motion through space actually creates alterations in the flow of time. The faster you move through the three dimensions that define physical space, the more slowly you’re moving through the fourth dimension, time––at least relative to another object. Time is measured differently for the twin who moved through space and the twin who stayed on Earth. The clock in motion will tick more slowly than the clocks we’re watching on Earth. If you’re able to travel near the speed of light, the effects are much more pronounced. 

Unlike the Twin Paradox, time dilation isn’t a thought experiment or a hypothetical concept––it’s real. The 1971 Hafele-Keating experiments proved as much, when two atomic clocks were flown on planes traveling in opposite directions. The relative motion actually had a measurable impact and created a time difference between the two clocks. This has also been confirmed in other physics experiments (e.g., fast-moving muon particles take longer to decay ). 

So in your question, an astronaut returning from a space journey at “relativistic speeds” (where the effects of relativity start to manifest—generally at least one-tenth the speed of light ) would, upon return, be younger than same-age friends and family who stayed on Earth. Exactly how much younger depends on exactly how fast the spacecraft had been moving and accelerating, so it’s not something we can readily answer. But if you’re trying to reach an exoplanet 10 to 50 light-years away and still make it home before you yourself die of old age, you’d have to be moving at close to light speed. 

There’s another wrinkle here worth mentioning: time dilation as a result of gravitational effects. You might have seen Christopher Nolan’s movie Interstellar , where the close proximity of a black hole causes time on another planet to slow down tremendously (one hour on that planet is seven Earth years).

This form of time dilation is also real, and it’s because in Einstein’s theory of general relativity, gravity can bend spacetime, and therefore time itself. The closer the clock is to the source of gravitation, the slower time passes; the farther away the clock is from gravity, the faster time will pass. (We can save the details of that explanation for a future Airlock.)

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Why is the speed of light the way it is?

It's just plain weird.

Paul M. Sutter is an astrophysicist at SUNY Stony Brook and the Flatiron Institute, host of Ask a Spaceman and Space Radio , and author of " How to Die in Space ." He contributed this article to Space.com's Expert Voices: Op-Ed & Insights . 

We all know and love the speed of light — 299,792,458 meters per second — but why does it have the value that it does? Why isn't it some other number? And why do we care so much about some random speed of electromagnetic waves? Why did it become such a cornerstone of physics? 

Well, it's because the speed of light is just plain weird.

Related: Constant speed of light: Einstein's special relativity survives a high-energy test

Putting light to the test

The first person to realize that light does indeed have a speed at all was an astronomer by the name of Ole Romer. In the late 1600s, he was obsessed with some strange motions of the moon Io around Jupiter. Every once in a while, the great planet would block our view of its little moon, causing an eclipse, but the timing between eclipses seemed to change over the course of the year. Either something funky was happening with the orbit of Io — which seemed suspicious — or something else was afoot.

After a couple years of observations, Romer made the connection. When we see Io get eclipsed, we're in a certain position in our own orbit around the sun. But by the next time we see another eclipse, a few days later, we're in a slightly different position, maybe closer or farther away from Jupiter than the last time. If we are farther away than the last time we saw an eclipse, then that means we have to wait a little bit of extra time to see the next one because it takes that much longer for the light to reach us, and the reverse is true if we happen to be a little bit closer to Jupiter.

The only way to explain the variations in the timing of eclipses of Io is if light has a finite speed.

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Making it mean something

Continued measurements over the course of the next few centuries solidified the measurement of the speed of light, but it wasn't until the mid-1800s when things really started to come together. That's when the physicist James Clerk Maxwell accidentally invented light.

Maxwell had been playing around with the then-poorly-understood phenomena of electricity and magnetism when he discovered a single unified picture that could explain all the disparate observations. Laying the groundwork for what we now understand to be the electromagnetic force , in those equations he discovered that changing electric fields can create magnetic fields, and vice versa. This allows waves of electricity to create waves of magnetism, which go on to make waves of electricity and back and forth and back and forth, leapfrogging over each other, capable of traveling through space.

And when he went to calculate the speed of these so-called electromagnetic waves, Maxwell got the same number that scientists had been measuring as the speed of light for centuries. Ergo, light is made of electromagnetic waves and it travels at that speed, because that is exactly how quickly waves of electricity and magnetism travel through space.

And this was all well and good until Einstein came along a few decades later and realized that the speed of light had nothing to do with light at all. With his special theory of relativity , Einstein realized the true connection between time and space, a unified fabric known as space-time. But as we all know, space is very different than time. A meter or a foot is very different than a second or a year. They appear to be two completely different things.

So how could they possibly be on the same footing?

There needed to be some sort of glue, some connection that allowed us to translate between movement in space and movement in time. In other words, we need to know how much one meter of space, for example, is worth in time. What's the exchange rate? Einstein found that there was a single constant, a certain speed, that could tell us how much space was equivalent to how much time, and vice versa.

Einstein's theories didn't say what that number was, but then he applied special relativity to the old equations of Maxwell and found that this conversion rate is exactly the speed of light.

Of course, this conversion rate, this fundamental constant that unifies space and time, doesn't know what an electromagnetic wave is, and it doesn't even really care. It's just some number, but it turns out that Maxwell had already calculated this number and discovered it without even knowing it. That's because all massless particles are able to travel at this speed, and since light is massless, it can travel at that speed. And so, the speed of light became an important cornerstone of modern physics.

But still, why that number, with that value, and not some other random number? Why did nature pick that one and no other? What's going on?

Related: The genius of Albert Einstein: his life, theories and impact on science

Making it meaningless

Well, the number doesn't really matter. It has units after all: meters per second. And in physics any number that has units attached to it can have any old value it wants, because it means you have to define what the units are. For example, in order to express the speed of light in meters per second, first you need to decide what the heck a meter is and what the heck a second is. And so the definition of the speed of light is tied up with the definitions of length and time.

In physics, we're more concerned with constants that have no units or dimensions — in other words, constants that appear in our physical theories that are just plain numbers. These appear much more fundamental, because they don't depend on any other definition. Another way of saying it is that, if we were to meet some alien civilization , we would have no way of understanding their measurement of the speed of light, but when it comes to dimensionless constants, we can all agree. They're just numbers.

One such number is known as the fine structure constant, which is a combination of the speed of light, Planck's constant , and something known as the permittivity of free space. Its value is approximately 0.007. 0.007 what? Just 0.007. Like I said, it's just a number.

So on one hand, the speed of light can be whatever it wants to be, because it has units and we need to define the units. But on the other hand, the speed of light can't be anything other than exactly what it is, because if you were to change the speed of light, you would change the fine structure constant. But our universe has chosen the fine structure constant to be approximately 0.007, and nothing else. That is simply the universe we live in, and we get no choice about it at all. And since this is fixed and universal, the speed of light has to be exactly what it is.

So why is the fine structure constant exactly the number that it is, and not something else? Good question. We don't know.

Learn more by listening to the episode "Why is the speed of light the way it is?" on the Ask A Spaceman podcast, available on iTunes and on the Web at http://www.askaspaceman.com. Thanks to Robert H, Michael E., @DesRon94, Evan W., Harry A., @twdixon, Hein P., Colin E., and Lothian53 for the questions that led to this piece! Ask your own question on Twitter using #AskASpaceman or by following Paul @PaulMattSutter and facebook.com/PaulMattSutter.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: [email protected].

Paul M. Sutter is an astrophysicist at SUNY Stony Brook and the Flatiron Institute in New York City. Paul received his PhD in Physics from the University of Illinois at Urbana-Champaign in 2011, and spent three years at the Paris Institute of Astrophysics, followed by a research fellowship in Trieste, Italy, His research focuses on many diverse topics, from the emptiest regions of the universe to the earliest moments of the Big Bang to the hunt for the first stars. As an "Agent to the Stars," Paul has passionately engaged the public in science outreach for several years. He is the host of the popular "Ask a Spaceman!" podcast, author of "Your Place in the Universe" and "How to Die in Space" and he frequently appears on TV — including on The Weather Channel, for which he serves as Official Space Specialist.

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• voidpotentialenergy This is just my opinion but i think L speed is it's speed because the particle part of it is the fastest it can interact with the quanta distance in quantum fluctuation. Light is particle and wave so the wave happens in the void between quanta. Gravity probably travels in that void and why gravity seems instant. Reply
• rod The space.com article wraps up the discussion with, "So on one hand, the speed of light can be whatever it wants to be, because it has units and we need to define the units. But on the other hand, the speed of light can't be anything other than exactly what it is, because if you were to change the speed of light, you would change the fine structure constant. But our universe has chosen the fine structure constant to be approximately 0.007, and nothing else. That is simply the universe we live in, and we get no choice about it at all. And since this is fixed and universal, the speed of light has to be exactly what it is. So why is the fine structure constant exactly the number that it is, and not something else? Good question. We don't know." It seems that the *universe* made this decision, *But our universe has chosen the fine structure constant to be...* I did not know that the universe was capable of making decisions concerning constants used in physics. E=mc^2 is a serious constant. Look at nuclear weapons development, explosive yields, and stellar evolution burn rates for p-p chain and CNO fusion rates. The report indicates why alpha (fine structure constant) is what it is and c is what it is, *We don't know*. Reply

Admin said: We all know and love the speed of light, but why does it have the value that it does? Why isn't it some other number? And why did it become such a cornerstone of physics? Why is the speed of light the way it is? : Read more

rod said: The space.com article wraps up the discussion with, "So on one hand, the speed of light can be whatever it wants to be, because it has units and we need to define the units. But on the other hand, the speed of light can't be anything other than exactly what it is, because if you were to change the speed of light, you would change the fine structure constant. But our universe has chosen the fine structure constant to be approximately 0.007, and nothing else. That is simply the universe we live in, and we get no choice about it at all. And since this is fixed and universal, the speed of light has to be exactly what it is. So why is the fine structure constant exactly the number that it is, and not something else? Good question. We don't know." It seems that the *universe* made this decision, *But our universe has chosen the fine structure constant to be...* I did not know that the universe was capable of making decisions concerning constants used in physics. E=mc^2 is a serious constant. Look at nuclear weapons development, explosive yields, and stellar evolution burn rates for p-p chain and CNO fusion rates. The report indicates why alpha (fine structure constant) is what it is and c is what it is, *We don't know*.

• rod FYI. When someone says *the universe has chosen*, I am reminded of these five lessons from a 1982 Fed. court trial. The essential characteristics of science are: It is guided by natural law; It has to be explanatory by reference to natural law; It is testable against the empirical world; Its conclusions are tentative, i.e., are not necessarily the final word; and It is falsifiable. Five important points about science. Reply
• Gary If the universe is expanding , how can the speed of light be constant ( miles per second , if each mile is getting longer ) ? Can light's velocity be constant while the universe expands ? So, with the expansion of the universe , doesn't the speed of light need to increase in order to stay at a constant velocity in miles per second ? Or, do the miles in the universe remain the same length as the universe 'adds' miles to its diameter ? Are the miles lengthening or are they simply being added / compounded ? Reply
• Gary Lets say we're in outer space and we shoot a laser through a block of glass. What causes the speed of the laser light to return to the speed it held prior to entering the block of glass ? Is there some medium in the vacuum of space that governs the speed of light ? Do the atoms in the glass push it back up to its original speed. If so, why don't those same atoms constantly push the light while it travels through the block of glass ? Reply

Gary said: Lets say we're in outer space and we shoot a laser through a block of glass. What causes the speed of the laser light to return to the speed it held prior to entering the block of glass ? Is there some medium in the vacuum of space that governs the speed of light ? Do the atoms in the glass push it back up to its original speed. If so, why don't those same atoms constantly push the light while it travels through the block of glass ?

Gary said: If the universe is expanding , how can the speed of light be constant ( miles per second , if each mile is getting longer ) ? Can light's velocity be constant while the universe expands ? So, with the expansion of the universe , doesn't the speed of light need to increase in order to stay at a constant velocity in miles per second ? Or, do the miles in the universe remain the same length as the universe 'adds' miles to its diameter ? Are the miles lengthening or are they simply being added / compounded ?

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May 8, 2014

Does light experience time?

by Fraser Cain, Universe Today

Have you ever noticed that time flies when you're having fun? Well, not for light. In fact, photons don't experience any time at all. Here's a mind-bending concept that should shatter your brain into pieces.

As you might know, I co-host Astronomy Cast, and get to pick the brain of the brilliant astrophysicist Dr. Pamela Gay every week about whatever crazy thing I think of in the shower. We were talking about photons one week and she dropped a bombshell on my brain. Photons do not experience time . [SNARK: Are you worried they might get bored?]

Just think about that idea. From the perspective of a photon, there is no such thing as time. It's emitted, and might exist for hundreds of trillions of years, but for the photon, there's zero time elapsed between when it's emitted and when it's absorbed again. It doesn't experience distance either. [SNARK: Clearly, it didn't need to borrow my copy of GQ for the trip.]

Since photons can't think, we don't have to worry too much about their existential horror of experiencing neither time nor distance, but it tells us so much about how they're linked together. Through his Theory of Relativity, Einstein helped us understand how time and distance are connected.

Let's do a quick review. If we want to travel to some distant point in space, and we travel faster and faster, approaching the speed of light our clocks slow down relative to an observer back on Earth. And yet, we reach our destination more quickly than we would expect. Sure, our mass goes up and there are enormous amounts of energy required, but for this example, we'll just ignore all that.

If you could travel at a constant acceleration of 1 g, you could cross billions of light years in a single human generation. Of course, your friends back home would have experienced billions of years in your absence, but much like the mass increase and energy required, we won't worry about them.

The closer you get to light speed , the less time you experience and the shorter a distance you experience. You may recall that these numbers begin to approach zero. According to relativity, mass can never move through the Universe at light speed. Mass will increase to infinity, and the amount of energy required to move it any faster will also be infinite. But for light itself, which is already moving at light speed… You guessed it, the photons reach zero distance and zero time.

Photons can take hundreds of thousands of years to travel from the core of the Sun until they reach the surface and fly off into space. And yet, that final journey, that could take it billions of light years across space, was no different from jumping from atom to atom.

Source: Universe Today

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Is time travel possible? Why one scientist says we 'cannot ignore the possibility.'

A common theme in science-fiction media , time travel is captivating. It’s defined by the late philosopher David Lewis in his essay “The Paradoxes of Time Travel” as “[involving] a discrepancy between time and space time. Any traveler departs and then arrives at his destination; the time elapsed from departure to arrival … is the duration of the journey.”

Time travel is usually understood by most as going back to a bygone era or jumping forward to a point far in the future . But how much of the idea is based in reality? Is it possible to travel through time? 

Is time travel possible?

According to NASA, time travel is possible , just not in the way you might expect. Albert Einstein’s theory of relativity says time and motion are relative to each other, and nothing can go faster than the speed of light , which is 186,000 miles per second. Time travel happens through what’s called “time dilation.”

Time dilation , according to Live Science, is how one’s perception of time is different to another's, depending on their motion or where they are. Hence, time being relative. 

Learn more: Best travel insurance

Dr. Ana Alonso-Serrano, a postdoctoral researcher at the Max Planck Institute for Gravitational Physics in Germany, explained the possibility of time travel and how researchers test theories. 

Space and time are not absolute values, Alonso-Serrano said. And what makes this all more complex is that you are able to carve space-time .

“In the moment that you carve the space-time, you can play with that curvature to make the time come in a circle and make a time machine,” Alonso-Serrano told USA TODAY. 

She explained how, theoretically, time travel is possible. The mathematics behind creating curvature of space-time are solid, but trying to re-create the strict physical conditions needed to prove these theories can be challenging. 

“The tricky point of that is if you can find a physical, realistic, way to do it,” she said. 

Alonso-Serrano said wormholes and warp drives are tools that are used to create this curvature. The matter needed to achieve curving space-time via a wormhole is exotic matter , which hasn’t been done successfully. Researchers don’t even know if this type of matter exists, she said.

“It's something that we work on because it's theoretically possible, and because it's a very nice way to test our theory, to look for possible paradoxes,” Alonso-Serrano added.

“I could not say that nothing is possible, but I cannot ignore the possibility,” she said. 

She also mentioned the anecdote of  Stephen Hawking’s Champagne party for time travelers . Hawking had a GPS-specific location for the party. He didn’t send out invites until the party had already happened, so only people who could travel to the past would be able to attend. No one showed up, and Hawking referred to this event as "experimental evidence" that time travel wasn't possible.

What did Albert Einstein invent?: Discoveries that changed the world

Just Curious for more? We've got you covered

USA TODAY is exploring the questions you and others ask every day. From "How to watch the Marvel movies in order" to "Why is Pluto not a planet?" to "What to do if your dog eats weed?" – we're striving to find answers to the most common questions you ask every day. Head to our Just Curious section to see what else we can answer for you. 

Speed of Light Calculator

Table of contents

With this speed of light calculator, we aim to help you calculate the distance light can travel in a fixed time . As the speed of light is the fastest speed in the universe, it would be fascinating to know just how far it can travel in a short amount of time.

We have written this article to help you understand what the speed of light is , how fast the speed of light is , and how to calculate the speed of light . We will also demonstrate some examples to help you understand the computation of the speed of light.

What is the speed of light? How fast is the speed of light?

The speed of light is scientifically proven to be the universe's maximum speed. This means no matter how hard you try, you can never exceed this speed in this universe. Hence, there are also some theories on getting into another universe by breaking this limit. You can understand this more using our speed calculator and distance calculator .

So, how fast is the speed of light? The speed of light is 299,792,458 m/s in a vacuum. The speed of light in mph is 670,616,629 mph . With this speed, one can go around the globe more than 400,000 times in a minute!

One thing to note is that the speed of light slows down when it goes through different mediums. Light travels faster in air than in water, for instance. This phenomenon causes the refraction of light.

Now, let's look at how to calculate the speed of light.

How to calculate the speed of light?

As the speed of light is constant, calculating the speed of light usually falls on calculating the distance that light can travel in a certain time period. Hence, let's have a look at the following example:

• Source: Light
• Speed of light: 299,792,458 m/s
• Time traveled: 100 seconds

You can perform the calculation in three steps:

Determine the speed of light.

As mentioned, the speed of light is the fastest speed in the universe, and it is always a constant in a vacuum. Hence, the speed of light is 299,792,458 m/s .

Determine the time that the light has traveled.

The next step is to know how much time the light has traveled. Unlike looking at the speed of a sports car or a train, the speed of light is extremely fast, so the time interval that we look at is usually measured in seconds instead of minutes and hours. You can use our time lapse calculator to help you with this calculation.

For this example, the time that the light has traveled is 100 seconds .

Calculate the distance that the light has traveled.

The final step is to calculate the total distance that the light has traveled within the time . You can calculate this answer using the speed of light formula:

distance = speed of light × time

Thus, the distance that the light can travel in 100 seconds is 299,792,458 m/s × 100 seconds = 29,979,245,800 m

What is the speed of light in mph when it is in a vacuum?

The speed of light in a vacuum is 670,616,629 mph . This is equivalent to 299,792,458 m/s or 1,079,252,849 km/h. This is the fastest speed in the universe.

Is the speed of light always constant?

Yes , the speed of light is always constant for a given medium. The speed of light changes when going through different mediums. For example, light travels slower in water than in air.

How can I calculate the speed of light?

You can calculate the speed of light in three steps:

Determine the distance the light has traveled.

Apply the speed of light formula :

speed of light = distance / time

How far can the speed of light travel in 1 minute?

Light can travel 17,987,547,480 m in 1 minute . This means that light can travel around the earth more than 448 times in a minute.

Speed of light

The speed of light in the medium. In a vacuum, the speed of light is 299,792,458 m/s.

Can anything travel faster than the speed of light?

Does it matter if it's in a vacuum?

In 1676, by studying the motion of Jupiter's moon Io, Danish astronomer Ole Rømer calculated that light travels at a finite speed. Two years later, building on data gathered by Rømer, Dutch mathematician and scientist Christiaan Huygens became the first person to attempt to determine the actual speed of light, according to the American Museum of Natural History in New York City. Huygens came up with a figure of 131,000 miles per second (211,000 kilometers per second), a number that isn't accurate by today's standards — we now know that the speed of light in the "vacuum" of empty space is about 186,282 miles per second (299,792 km per second) — but his assessment showcased that light travels at an incredible speed.

According to Albert Einstein 's theory of special relativity , light travels so fast that, in a vacuum, nothing in the universe is capable of moving faster. 

"We cannot move through the vacuum of space faster than the speed of light," confirmed Jason Cassibry, an associate professor of aerospace engineering at the Propulsion Research Center, University of Alabama in Huntsville.

Question answered, right? Maybe not. When light is not in a vacuum, does the rule still apply?

Related: How many atoms are in the observable universe?

"Technically, the statement 'nothing can travel faster than the speed of light' isn't quite correct by itself," at least in a non-vacuum setting, Claudia de Rham, a theoretical physicist at Imperial College London, told Live Science in an email. But there are certain caveats to consider, she said. Light exhibits both particle-like and wave-like characteristics, and can therefore be regarded as both a particle (a photon ) and a wave. This is known as wave-particle duality.

If we look at light as a wave, then there are "multiple reasons" why certain waves can travel faster than white (or colorless) light in a medium, de Rham said. One such reason, she said, is that "as light travels through a medium — for instance, glass or water droplets — the different frequencies or colors of light travel at different speeds." The most obvious visual example of this occurs in rainbows, which typically have the long, faster red wavelengths at the top and the short, slower violet wavelengths at the bottom, according to a post by the University of Wisconsin-Madison . 

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When light travels through a vacuum, however, the same is not true. "All light is a type of electromagnetic wave, and they all have the same speed in a vacuum (3 x 10^8 meters per second). This means both radio waves and gamma rays have the same speed," Rhett Allain, a physics professor at Southeastern Louisiana University, told Live Science in an email.

So, according to de Rham, the only thing capable of traveling faster than the speed of light is, somewhat paradoxically, light itself, though only when not in the vacuum of space. Of note, regardless of the medium, light will never exceed its maximum speed of 186,282 miles per second.

Universal look

According to Cassibry, however, there is something else to consider when discussing things moving faster than the speed of light.

"There are parts of the universe that are expanding away from us faster than the speed of light, because space-time is expanding," he said. For example, the Hubble Space Telescope recently spotted 12.9 billion year-old light from a distant star known as Earendel. But, because the universe is expanding at every point, Earendel is moving away from Earth and has been since its formation, so the galaxy is now 28 billion light years away from Earth.

In this case, space-time is expanding, but the material in space-time is still traveling within the bounds of light speed.

Related: Why is space a vacuum?

So, it's clear that nothing travels faster than light that we know of, but is there any situation where it might be possible? Einstein's theory of special relativity, and his subsequent theory of general relativity, is "built under the principle that the notions of space and time are relative," de Rham said. But what does this mean? "If someone [were] able to travel faster than light and carry information with them, their notion of time would be twisted as compared to ours," de Rham said. "There could be situations where the future could affect our past, and then the whole structure of reality would stop making sense."

This would indicate that it would probably not be desirable to make a human travel faster than the speed of light. But could it ever be possible? Will there ever be a time when we are capable of creating craft that could propel materials — and ultimately humans — through space at a pace that outstrips light speed? "Theorists have proposed various types of warp bubbles that could enable faster-than-light travel," Cassibry said.

But is de Rham convinced?

"We can imagine being able to communicate at the speed of light with systems outside our solar system ," de Rham said. "But sending actual physical humans at the speed of light is simply impossible, because we cannot accelerate ourselves to such speed.

"Even in a very idealistic situation where we imagine we could keep accelerating ourselves at a constant rate — ignoring how we could even reach a technology that could keep accelerating us continuously — we would never actually reach the speed of light," she added. "We could get close, but never quite reach it."

Related: How long is a galactic year?

This is a point confirmed by Cassibry. "Neglecting relativity, if you were to accelerate with a rate of 1G [Earth gravity], it would take you a year to reach the speed of light. However, you would never really reach that velocity because as you start to approach lightspeed, your mass energy increases, approaching infinite. "One of the few known possible 'cheat codes' for this limitation is to expand and contract spacetime, thereby pulling your destination closer to you. There seems to be no fundamental limit on the rate at which spacetime can expand or contract, meaning we might be able to get around this velocity limit someday."

— What would happen if the speed of light were much lower?

— What if the speed of sound were as fast as the speed of light?

— How does the rubber pencil illusion work?

Allain is similarly confident that going faster than light is far from likely, but, like Cassibry, noted that if humans want to explore distant planets, it may not actually be necessary to reach such speeds. "The only way we could understand going faster than light would be to use some type of wormhole in space," Allain said. "This wouldn't actually make us go faster than light, but instead give us a shortcut to some other location in space."

Cassibry, however, is unsure if wormholes will ever be a realistic option.

"Wormholes are theorized to be possible based on a special solution to Einstein's field equations," he said. "Basically, wormholes, if possible, would give you a shortcut from one destination to another. I have no idea if it's possible to construct one, or how we would even go about doing it." Originally published on Live Science.

Joe Phelan is a journalist based in London. His work has appeared in VICE, National Geographic, World Soccer and The Blizzard, and has been a guest on Times Radio. He is drawn to the weird, wonderful and under examined, as well as anything related to life in the Arctic Circle. He holds a bachelor's degree in journalism from the University of Chester. 

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Here's What Actually Happens When You Travel at the Speed of Light, According to NASA

NASA created a fun video to answer all of our burning questions about near-light-speed travel.

Ever wish you could travel at the speed of light to your favorite destinations ? Once you see the reality of that speed, you may rethink everything.

"There are some important things you should probably know about approaching the speed of light," NASA's video, Guide to Near-light-speed Travel , explains. "First, a lot of weird things can happen, like time and space getting all bent out of shape."

According to the video, if you're traveling at nearly the speed of light, the clock inside your rocket would show it takes less time to travel to your destination than it would on Earth. But, since the clocks at home would be moving at a standard rate you'd return home to everyone else being quite a bit older.

"Also, because you're going so fast, what would otherwise be just a few hydrogen atoms that you'd run into quickly becomes a lot of dangerous particles. So you should probably have shields that keep them from frying your ship and also you."

Finally, the video tackles the fact that even if you were moving at the speed of light, the "universe is also a very big place, so you might be in for some surprises." For example, your rocket's clock will say it takes about nine months to get from Earth to the edge of the solar system. An Earth clock would say it took about a year and a half. Fortunately, NASA astronauts have a slew of tips for avoiding jet lag along the way.

"If you want to get to farther out vacation spots," the video explains, "you'll probably need more than a few extra snacks. A trip to the Andromeda Galaxy, our nearest large neighbor galaxy, can take over one million years. And a trip to the farthest known galaxy where it currently sits might take over 15 billion years, which is more vacation time than I think I'll ever have."

The video doesn't explain how your rocket will travel at the speed of light. Our technology just isn't there yet, but maybe the aliens will share that tech with us soon. Until then, you can track the first crew launch of Artemis II , a rocket that will fly around the moon in 2024 before making its first lunar landing in 2025.

What If Humans Traveled at the Speed of Light? Here's What Happens

S pace is always ripe for theoretical thought exercises, such as the intriguing question, “What would happen if humans traveled at the speed of light?”

Knewz.com has learned that humans would probably not realize we were moving at the speed of light because we cannot feel constant velocity.

However, the main problem would be accelerating to the 671 million miles per hour that light travels, according to an interview published by Space.com .

Rapid acceleration can be extremely painful and even deadly to humans, and we can only handle forces of four to six times the pull of gravity (4 to 6 gs). That makes the 6,000 gs of accelerating to the speed of light completely untenable.

Even more reasonable gs from endeavors like taking off on a space rocket or flying a fighter jet can kill a person because the force makes it difficult for the body to pump blood from the feet to the brain, which is why passing out is such a threat for pilots.

“Your blood will have a hard time pumping to your extremities,” said Michael Pravica, a professor of physics at the University of Nevada, Las Vegas, in the article.

If the g-force does not subside, the person will die because the blood is no longer transporting oxygen throughout the body.

That being said, 6,000 gs would flatten the person like a pancake before that ever became an issue.

The article posited that humans could potentially travel at the speed of light if they accelerated slowly. At the rate of a free fall (1 g), it would take 11 months to reach the speed of light.

Unfortunately, physics still presents a problem, specifically Einstein’s theory of relativity. As objects travel closer to the speed of light, their mass starts to grow, and the theory has proven that it would require infinite mass to travel at the speed of light.

This problem of physics is why humans have never managed to get anything to travel at the speed of light. Scientists have pushed sub-atomic particles to move at 99.9% the speed of light, but never 100%.

As humans are much larger than sub-atomic particles, the amount of energy required to push a human even to 99.9% the speed of light would be “extremely improbable” said Pravica.

However, suppose we allow ourselves to break physics and enable a person to travel at the speed of light, Einstein's theory of relativity argues that the person would age incredibly slowly thanks to time dilation.

Additionally, despite aging slower, people moving at normal speed would appear to be moving in slow motion. So, the speed-of-light travellers would simultaneously be moving much faster than their slow-motion peers while also aging slower.

One fascinating idea is that the speed of light is a foundation of modern physics, but there is no true rule that light must be the fastest object in the universe, according to Discover Magazine .

Our current understanding of physics puts light as the limit of speed, but humans in the distant future could theoretically experience a breakthrough and discover a means to travel faster than the speed of light.

While the idea is fun to ponder, there are significant hurdles that essentially guarantee humans will not be able to travel at the speed of light anytime in the foreseeable future.

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Voyager 1 transmitting data again after Nasa remotely fixes 46-year-old probe

Engineers spent months working to repair link with Earth’s most distant spacecraft, says space agency

Earth’s most distant spacecraft, Voyager 1, has started communicating properly again with Nasa after engineers worked for months to remotely fix the 46-year-old probe.

Nasa’s Jet Propulsion Laboratory (JPL), which makes and operates the agency’s robotic spacecraft, said in December that the probe – more than 15bn miles (24bn kilometres) away – was sending gibberish code back to Earth.

In an update released on Monday , JPL announced the mission team had managed “after some inventive sleuthing” to receive usable data about the health and status of Voyager 1’s engineering systems. “The next step is to enable the spacecraft to begin returning science data again,” JPL said. Despite the fault, Voyager 1 had operated normally throughout, it added.

Launched in 1977, Voyager 1 was designed with the primary goal of conducting close-up studies of Jupiter and Saturn in a five-year mission. However, its journey continued and the spacecraft is now approaching a half-century in operation.

Voyager 1 crossed into interstellar space in August 2012, making it the first human-made object to venture out of the solar system. It is currently travelling at 37,800mph (60,821km/h).

Hi, it's me. - V1 https://t.co/jgGFBfxIOe — NASA Voyager (@NASAVoyager) April 22, 2024

The recent problem was related to one of the spacecraft’s three onboard computers, which are responsible for packaging the science and engineering data before it is sent to Earth. Unable to repair a broken chip, the JPL team decided to move the corrupted code elsewhere, a tricky job considering the old technology.

The computers on Voyager 1 and its sister probe, Voyager 2, have less than 70 kilobytes of memory in total – the equivalent of a low-resolution computer image. They use old-fashioned digital tape to record data.

The fix was transmitted from Earth on 18 April but it took two days to assess if it had been successful as a radio signal takes about 22 and a half hours to reach Voyager 1 and another 22 and a half hours for a response to come back to Earth. “When the mission flight team heard back from the spacecraft on 20 April, they saw that the modification worked,” JPL said.

Alongside its announcement, JPL posted a photo of members of the Voyager flight team cheering and clapping in a conference room after receiving usable data again, with laptops, notebooks and doughnuts on the table in front of them.

The Retired Canadian astronaut Chris Hadfield, who flew two space shuttle missions and acted as commander of the International Space Station, compared the JPL mission to long-distance maintenance on a vintage car.

“Imagine a computer chip fails in your 1977 vehicle. Now imagine it’s in interstellar space, 15bn miles away,” Hadfield wrote on X . “Nasa’s Voyager probe just got fixed by this team of brilliant software mechanics.

Voyager 1 and 2 have made numerous scientific discoveries , including taking detailed recordings of Saturn and revealing that Jupiter also has rings, as well as active volcanism on one of its moons, Io. The probes later discovered 23 new moons around the outer planets.

As their trajectory takes them so far from the sun, the Voyager probes are unable to use solar panels, instead converting the heat produced from the natural radioactive decay of plutonium into electricity to power the spacecraft’s systems.

Nasa hopes to continue to collect data from the two Voyager spacecraft for several more years but engineers expect the probes will be too far out of range to communicate in about a decade, depending on how much power they can generate. Voyager 2 is slightly behind its twin and is moving slightly slower.

In roughly 40,000 years, the probes will pass relatively close, in astronomical terms, to two stars. Voyager 1 will come within 1.7 light years of a star in the constellation Ursa Minor, while Voyager 2 will come within a similar distance of a star called Ross 248 in the constellation of Andromeda.

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April 22, 2024

Making history: brightline west breaks ground on america’s first high-speed rail project connecting las vegas to southern california  , officials hammer the first spike commemorating the groundbreaking for brightline west.

LAS VEGAS (April 22, 2024)  – Today, Brightline West officially broke ground on the nation's first true high-speed rail system which will connect Las Vegas to Southern California. The 218-mile system will be constructed in the middle of the I-15 and is based on Brightline’s vision to connect city pairs that are too short to fly and too far to drive. Hailed as the greenest form of transportation in the world, Brightline West will run zero emission, fully electric trains capable of speeds of 200 miles per hour. Brightline West is a watershed project for high-speed rail in America and will establish the foundation for the creation of a new industry and supply chain. The project was recently awarded $3 billion in funding from President Biden’s Bipartisan Infrastructure Bill. The rest of the project will be privately funded and has received a total allocation of $3.5 billion in private activity bonds from USDOT.

The groundbreaking included remarks from U.S. Transportation Secretary Pete Buttigieg, Brightline Founder Wes Edens, Nevada Gov. Joe Lombardo, Sen. Catherine Cortez Masto, Sen. Jacky Rosen, Senior Advisor to President Biden Steve Benjamin and Vince Saavedra of the Southern Nevada Building Trades. In addition, Nevada Reps. Dina Titus, Susie Lee and Steve Horsford and California Reps. Pete Aguilar and Norma Torres made remarks and joined the celebration. More than 600 people, including union representatives, project supporters and other state and local officials from California and Nevada, attended the event.

“People have been dreaming of high-speed rail in America for decades – and now, with billions of dollars of support made possible by President Biden’s historic infrastructure law, it’s finally happening,” said Secretary Buttigieg. “Partnering with state leaders and Brightline West, we’re writing a new chapter in our country’s transportation story that includes thousands of union jobs, new connections to better economic opportunity, less congestion on the roads, and less pollution in the air.”

“This is a historic project and a proud moment where we break ground on America’s first high-speed rail system and lay the foundation for a new industry,” said Wes Edens, Brightline founder. “Today is long overdue, but the blueprint we’ve created with Brightline will allow us to repeat this model in other city pairs around the country.”

CONSTRUCTION OF BRIGHTLINE WEST

Brightline West's rail system will span 218 miles and reach speeds of 200 mph. The route, which has full environmental clearance, will run within the median of the I-15 highway with zero grade crossings. The system will have stops in Las Vegas, Nev., as well as Victor Valley, Hesperia and Rancho Cucamonga, Calif.

The privately led infrastructure project is one of the largest in the nation and will be constructed and operated by union labor. It will use 700,000 concrete rail ties, 2.2 million tons of ballast, and 63,000 tons of 100% American steel rail during construction. Upon completion, it will include 322 miles of overhead lines to power the trains and will include 3.4 million square feet of retaining walls. The project covers more than 160 structures including viaducts and bridges. Brightline West will be fully Buy America Compliant.

STATIONS AND FACILITIES

Brightline West will connect Southern California and Las Vegas in two hours or almost half the time as driving. The Las Vegas Station will be located near the iconic Las Vegas Strip, on a 110-acre property north of Blue Diamond Road between I-15 and Las Vegas Boulevard. The site provides convenient access to the Harry Reid International Airport, the Las Vegas Convention Center and the Raiders’ Allegiant Stadium. The station is approximately 80,000 square feet plus parking.

The Victor Valley Station in Apple Valley will be located on a 300-acre parcel southeast of Dale Evans Parkway and the I-15 interchange. The station is intended to offer a future connection to the High Desert Corridor and California High Speed Rail. The Victor Valley Station is approximately 20,000 square feet plus parking.

The Rancho Cucamonga Station will be located on a 5-acre property at the northwest corner of Milliken Avenue and Azusa Court near Ontario International Airport. The station will be co-located with existing multi-modal transportation options including California Metrolink, for seamless connectivity to Downtown Los Angeles and other locations in Los Angeles, Orange, San Bernardino and Riverside Counties. The Rancho Cucamonga Station is approximately 80,000 square feet plus parking.

The Hesperia Station will be located within the I-15 median at the I-15/Joshua Street interchange and will function primarily as a local rail service for residents in the High Desert on select southbound morning and northbound evening weekday trains.

The Vehicle Maintenance Facility (VMF) is a 200,000-square-foot building located on 238 acres in Sloan, Nev., and will be the base for daily maintenance and staging of trains. This site will also serve as one of two hubs for the maintenance of way operations and the operations control center. More than 100 permanent employees will report on a daily basis once operations begin and will serve as train crews, corridor maintenance crews, or operations control center teammates. A second maintenance of way facility will be located adjacent to the Apple Valley station.

The Las Vegas and Southern California travel market is one of the nation’s most attractive corridors with over 50 million trips between the region each year. Additionally, Las Vegas continues to attract visitors from around the world, with 4.7 million international travelers flying into the destination. The city dubs itself on being the world’s No. 1 meeting destination, welcoming nearly 6 million people to the Las Vegas Convention Center last year.

In California, approximately 17 million Southern California residents are within 25 miles of the Brightline West station sites. Studies show that one out of every three visits to Las Vegas come from Southern California.

ECONOMIC & ENVIRONMENTAL BENEFITS

Brightline West's $12 billion infrastructure investment will create over $10 billion in economic impact for Nevada and California and will generate more than 35,000 jobs, including 10,000 direct union construction roles and 1,000 permanent operations and maintenance positions. The investment also includes over $800 million in improvements to the I-15 corridor and involves agreements with several unions for skilled labor. The project supports Nevada and California's climate goals by offering a no-emission mobility option that reduces greenhouse gasses by over 400,000 tons of CO2 annually – reducing vehicle miles traveled by more than 700 million each year and the equivalent of 16,000 short-haul flights. The company will also construct three wildlife overpasses, in partnership with the California Department of Fish and Wildlife and Caltrans for the safe passage of native species, primarily the bighorn sheep.

BRIGHTLINE FLORIDA

Brightline’s first rail system in Florida connecting Miami to Orlando began initial service between its South Florida stations in 2018. In September 2023, Brightline’s Orlando station opened at Orlando International Airport, connecting South Florida to Central Florida. The company has plans to expand its system with future stops in Tampa, Florida’s Space Coast in Cocoa and the Treasure Coast in Stuart.

BRIGHTLINE WEST

ABOUT BRIGHTLINE WEST

Brightline is the only private provider of modern, eco-friendly, intercity passenger rail service in America – offering a guest-first experience designed to reinvent train travel and take cars off the road by connecting city pairs and congested corridors that are too short to fly and too long to drive. Brightline West will connect Las Vegas and Southern California with the first true high-speed passenger rail system in the nation. The 218-mile, all-electric rail service will include a flagship station in Las Vegas, with additional stations in Victor Valley and Rancho Cucamonga. At speeds up to 200 miles per hour, trains will take passengers from Las Vegas to Rancho Cucamonga in about two hours, twice as fast as the normal drive time.

Brightline is currently operating its first passenger rail system connecting Central and South Florida with stations in Miami, Aventura, Fort Lauderdale, Boca Raton, West Palm Beach, and Orlando, with future stations coming to Stuart and Cocoa. For more information, visit  www.brightlinewest.com  and follow on  LinkedIn ,  X ,  Instagram  and  Facebook .

QUOTE SHEET

“Through this visionary partnership, we are going to create thousands of jobs, bring critical transportation infrastructure to the West, and create an innovative, fast, and sustainable transportation solution. Nevada looks forward to partnering with Brightline on this historic project.”  - Governor Joe Lombardo, Nevada

“Today, not only are we breaking ground on a historic high-speed rail project here in Nevada, we are breaking ground on thousands of good paying American jobs, union jobs.”  - Steve Benjamin, Senior Advisor to the President and Director of the White House Office of Public Engagement

“For decades, Nevadans heard about the promise of high-speed rail in our state, and I’m proud to have led the charge to secure the funding to make it a reality. Today’s groundbreaking is the beginning of a new era for southern Nevada -- creating thousands of good-paying union jobs, bringing in billions of dollars of economic development, enhancing tourism to the state, reducing traffic, and creating a more efficient and cleaner way to travel. This is a monumental step, and I’m glad to have worked across the aisle to make this project come true.”  - Senator Jacky Rosen (D-NV)

“Having high-speed rail in Las Vegas will electrify our economy in Southern Nevada, and I’m thrilled to celebrate this milestone today. This project is on track to create tens of thousands of good-paying union jobs while cutting down traffic on I-15, and I’ll keep working with the Biden Administration to get this done as quickly as possible and continue delivering easier and cleaner transportation options for everyone in Nevada.”  - Senator Catherine Cortez Masto (D-NV)

“Today’s groundbreaking is a historic step in modernizing rail service in the United States. Californians driving between the Los Angeles region and Las Vegas often face heavy traffic, causing emissions that pollute the air in surrounding communities. The Brightline West Project will provide travelers with more options—helping Californians and visitors alike get to their final destination without facing gridlock on the road.”  - Senator Alex Padilla (D-Calif.)

"High-speed rail in the Southwest has been a dream as far back as the nineties when Governor Bob Miller appointed me to the California-Nevada Super Speed Train Commission. As a senior Member of the House Transportation & Infrastructure Committee, I am honored to have helped write the Bipartisan Infrastructure Law and secure $3 billion to turn that dream into a reality which will generate millions of dollars in tax revenue, reduce carbon emissions by easing traffic on Interstate 15, and create thousands of good-paying union jobs. I am proud to stand with advocates and transportation leaders as we break ground on the Brightline West project and look forward to welcoming high-speed passenger rail to Southern Nevada."  - Congresswoman Dina Titus (NV-1)

“For decades, high-speed rail was just a dream in southern Nevada – but now, I’m beyond proud that we finally made it a reality. I worked across the aisle to help negotiate, craft, and ultimately pass the Bipartisan Infrastructure Law because I knew it would kickstart transformative projects like Brightline West that will stand the test of time. Together, we’re cutting down on traffic, boosting our tourism economy, and creating thousands of good-paying union jobs.”  - Congresswoman Susie Lee (NV-3)

“I am proud to join Brightline West for the groundbreaking of this monumental project for Southern Nevada and the southwestern United States. By connecting Las Vegas to Southern California via high-speed rail, we will boost tourism, reduce congestion on the I-15 corridor, and create jobs. The impact on our local economy and the people of the Silver State will be tremendous. In my conversations with Secretary Buttigieg, Brightline West, and our Nevada labor leaders, I know that local workers and our Nevada small businesses will benefit from this transformational investment. This will be the nation's first true high-speed rail system, blazing a new path forward for our nation’s rail infrastructure, and we hope it will serve as a blueprint for fostering greater regional connections for many other cities across the country.  - Congressman Steven Horsford (NV-4)

“Brightline West’s groundbreaking today marks the construction of a dynamic high-speed rail system that will link Las Vegas, Hesperia, and Apple Valley to Rancho Cucamonga’s Metrolink Station, creating new jobs and fostering economic growth in California’s 23rd Congressional District. This convenient alternative to driving will reduce the number of cars on the road, decreasing emissions and reducing congestion in our High Desert communities. This is an exciting step and I look forward to the completion of this project.”  - Congressman Jay Obernolte (CA-23)

"Today's groundbreaking on the Brightline West high-speed rail project marks an incredible milestone in the Biden-Harris Administration's commitment to fulfilling the promise of high-speed rail and emissions-free transportation across the country. As a longtime supporter of this project, I helped pass the Bipartisan Infrastructure Law, which has already invested over $3 billion to support the completion of this project. By increasing transportation options, spurring job creation and new economic opportunities, and improving our environment through cutting over 400,000 tons of carbon pollution each year, this project will be transformative to my district and all of Southern California for generations—particularly in and around the last stop in Rancho Cucamonga. With the goal of being operational in time for Los Angeles to host the Summer Olympic Games in 2028, I look forward to Brightline West facilitating travel for the millions visiting our region and elevating our 21st-century connectivity on the global stage."  - Congresswoman Judy Chu (CA-28)

"As the Member of Congress that represents the City of Rancho Cucamonga and a member of the House Appropriations Subcommittee on Transportation, Housing, and Urban Development, it is my honor to participate in breaking ground on one of the most highly anticipated high-speed rail projects in the country. We gathered today thanks to the Biden Administration's leadership, which enacted the Bipartisan Infrastructure Law and the Inflation Reduction Act to fund vital projects like this and transform our economy. The Brightline project is a stellar illustration of the power of successful public-private partnerships. Thanks to all the labor unions, Tribes, and wildlife advocates for their hard work, which brought this project to life. The bright line is fully electric and has zero emissions, which is excellent for our environment. I am eagerly anticipating the completion of this project in my district and look forward to seeing everyone there."  - Congresswoman Norma J. Torres (CA-35)

Media Contact

Vanessa Alfonso [email protected]

US finally breaks ground on its first-ever high-speed rail

The rail could connect Los Angeles and Las Vegas by the end of the decade.

By Mack DeGeurin | Published Apr 23, 2024 5:05 PM EDT

Builders have officially broken ground on a new $12 billion train that could zoom travelers between Las Vegas and Los Angeles in just under two hours by the end of the decade. The new train, which is considered the first “high-speed” rail in the United States, could cut down commute time for travelers and reduce greenhouse gas emissions that would otherwise be emitted from cars and planes. Brightline, the firm responsible for the project, received $3 billion in support from the federal government as part of the 2021 bipartisan Infrastructure law.

Department of Transportation Secretary Pete Buttigieg, who was one of several Biden Administration officials on site for a groundbreaking ceremony Monday, described the moment as a “major milestone in building the future of American rail.” The ceremony symbolically took place on Earth Day. 

“Partnering with state leaders and Brightline West, we’re writing a new chapter in our country’s transportation story that includes thousands of union jobs, new connections to better economic opportunity, less congestion on the roads, and less pollution in the air,” Buttigieg said in a statement . 

On behalf of the Biden administration, it was my great honor to help break ground on what's expected to be the first operating high-speed rail line in American history! pic.twitter.com/VJjz849t03 — Secretary Pete Buttigieg (@SecretaryPete) April 23, 2024

This day is a major milestone in building the future of American rail and the jobs that come with it. Today we celebrate the groundbreaking of the Brightline West high-speed rail project, connecting Las Vegas to Southern California. — Secretary Pete Buttigieg (@SecretaryPete) April 22, 2024

Brightline expects its trains will depart every 40 minutes from a station outside of the Vegas strip and another one in the LA suburb of Rancho Cucamonga. When it’s completed, the train will travel at 186 miles per hour, making it the fastest train in the US and comparable to Japan’s famous bullet trains. For context, Brightline’s most recently completed train connecting parts of Florida is estimated to top out around 130 miles per hour . Both of those still fall far short of the speed achieved by the world fastest commuter train in Shanghai, which can reportedly reach a speed of 286 miles per hour. Still, the new train could complete the 218 mile trip between Sin City and a suburb of the City of Angels in just 2 hours and 10 minutes. That same trip would take about four hours by car, and that’s without substantial traffic. 

Once built, the trains will reportedly include onboard Wi-Fi, restrooms, and food and drinks available for purchase. Brightline hasn’t provided an exact price for how much an individual train ticket will cost but has instead said they expect it to be roughly equivalent to the price of an airline flight. Brightline reportedly believes the train could attract 11 million one-way passengers annually once it’s up and running.

“Today is long overdue, but the blueprint we’ve created with Brightline will allow us to repeat this model in other city pairs around the country,” Brightline founder Wes Edens said in a statement. 

The US Department of Transportation estimates the new train could cut back 400,000 tons of carbon dioxide per year and create 35,000 new jobs. It could also help foster new, much-needed competition. Amtrak, the nation’s primary long distance rail provider, has long held a monopoly over long distance rail in the US, but many areas still remain unserved. Prior to this project, Las Vegas, for example, did not have Amtrak service. Brightline is looking to build out more trains in the coming decade, with a focus on connecting areas that commuters find too close to fly and too far to comfortably drive.

American high-speed rail is having a moment (finally)

US infrastructure policy has long favored automobiles over long-distance rail and mass transit, much to the consternation of climate activists who argue an over reliance on gas burning cars is contributing to worsening climate change . But there are signs the country’s attitude toward rails is beginning to change. Brightline, the same company attempting to link Las Vegas and LA, recently completed a first-of-its-kind train linking Miami, Aventura, Fort Lauderdale, Boca Raton, and West Palm Beach in Florida. Brightline reportedly claims its Florida train had 258,307 passengers in March. 

Elsewhere, other new high-speed train routes are being considered in Texas, the Pacific Northwest and other parts of California . Those efforts, if they materialize, will be made possible in part by billions of dollars worth of grants set aside for rail as part of the infrastructure law. Still, receiving funds and beginning projects are only the beginning of the battle. Rising costs and routing disputes can delay and complicate and delay actual development. One proposed rail line running roughly 300 miles between San Francisco and LA was first approved by voters in 2008 and has still yet to materialize . As of today, nearly two decades later, less than a quarter of that rail line has been completed. Brightline is hoping it can avoid those complications with its new high-speed rail. If it does, commuters could expect to make the trip between Sin City and Hollywood by 2028.

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Your how-to guide for the new Eastside light rail line

The East Link Starter Line, also called the 2 Line, begins service 11 a.m. Saturday with eight stops in Bellevue and Redmond. If you’re a newcomer to Sound Transit light rail, here’s what to know.

Hours: Eastside trains are scheduled to arrive every 10 minutes, seven days a week from 5:30 a.m. to 9:30 p.m.

Travel time: A ride on the 6-mile line, end to end, lasts 20 minutes.

Capacity: Two-car trains are intended to carry 300 people, when half are seated and half standing.

Locations: At the south end is South Bellevue Station. From there, trains head northeast to East Main, Bellevue Downtown, Wilburton, Spring District, BelRed, Overlake Village and the last stop, Redmond Technology Station. Free park-and-ride space is available at South Bellevue (1,500 stalls), BelRed (300), Overlake Village (203 stalls, four blocks away) and Redmond Technology (300). The other four stations include passenger drop-off sites and connecting bus stops.

Fares: Standard adult fares are $2.25 to $2.50 depending on distance. Link light rail charges $1 for 65+, disabled and low-income passengers holding a discounted ORCA fare card. People 18 and younger ride transit free throughout Washington state. Fares will be collected opening weekend.

How to pay: Fares are paid before entering trains. Most people use a regional ORCA fare card, tapping it on a yellow detector near the station entrance. Tap again when leaving a station to avoid overcharges. See orcacard.com to order fare cards online or find in-person sites . ORCA cards are available at many QFC and Fred Meyer stores. Paper single-trip and all-day tickets are sold in station vending machines, which accept cash or credit/debit cards. If you’re taking more than a couple of rides, it’s simpler to buy an ORCA fare card directly from the ticket machine. You pay $3 for the card, then load it with funds. Or download the Transit Go app .

Station entry: There are no turnstiles. “Fare ambassadors” canvass some trains to check for proof of payment and help people navigate. They issue advice or warnings and can cite repeat evaders for $50 or more. Pedestrians should look all ways for trains next to station platforms and at grade crossings around BelRed Station.

Bicycles: Bikes are allowed onboard light rail, hanging from a hook in a nook that doubles as luggage space.

Restrooms: There are no public restrooms in the eight stations.

Buses: The primary train-bus connections are I-90 routes that swing by South Bellevue Station; Highway 520 routes next to Redmond Technology Station; and I-405 buses that converge at Bellevue Downtown Station. Metro’s B Line bus links the Crossroads neighborhood to multiple train stops including Wilburton.

Traffic Lab | Eastside Light Rail

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• Eastside’s biggest employer has been getting ready for this day for years
• Eastside light rail line opens as huge crowds try out the ride
• The highs and lows of Eastside’s 8 new light rail stations, from parking to traffic hazards
• New to light rail? Here’s your starter kit for riding
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• Timeline: Eastside light rail has been a long time coming

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Midwest tornadoes cause severe damage in Omaha suburbs

The Associated Press

Gopala Penmetsa walks past his house after it was leveled by a tornado near Omaha, Neb., on Friday. Chris Machian/Omaha World-Herald via AP hide caption

Gopala Penmetsa walks past his house after it was leveled by a tornado near Omaha, Neb., on Friday.

OMAHA, Neb. — A tornado plowed through suburban Omaha, Nebraska, on Friday afternoon, damaging hundreds of homes and other structures as the twister tore for miles along farmland and into subdivisions. Injuries were reported but it wasn't yet clear if anyone was killed in the storm.

Multiple tornadoes were reported in Nebraska but the most destructive storm moved from a largely rural area into suburbs northwest of Omaha, a city of 485,000 people.

Photos on social media showed heavily damaged homes and shredded trees. Video showed homes with roofs stripped of shingles, in a rural area near Omaha. Law enforcement were blocking off roads in the area.

Hundreds of houses sustained damage in Omaha, mostly in the Elkhorn area in the western part of the city, police Lt. Neal Bonacci said.

Police and firefighters are now going door-to-door helping people who are trapped.

Omaha Fire Chief Kathy Bossman said crews had gone to the "hardest hit area" and had a plan to search anywhere someone could be trapped.

"They're going to be putting together a strategic plan for a detailed search of the area, starting with the properties with most damage," Bossman said. "We'll be looking throughout properties in debris piles, we'll be looking in basements, trying to find any victims and make sure everybody is rescued who needs assistance."

Damaged houses are seen after a tornado passed through the area near Omaha, Neb., on Friday. Chris Machian/Omaha World-Herald via AP hide caption

Damaged houses are seen after a tornado passed through the area near Omaha, Neb., on Friday.

Omaha police Lt. Neal Bonacci said many homes were destroyed or severely damaged.

"You definitely see the path of the tornado," Bonacci said.

In one area of Elkhorn, dozens of newly built, large homes were damaged. At least six were destroyed, including one that was leveled, while others had the top half ripped off.

There were dozens of emergency vehicles in the area.

"We watched it touch down like 200 yards over there and then we took shelter," said Pat Woods, who lives in Elkhorn. "We could hear it coming through. When we came up our fence was gone and we looked to the northwest and the whole neighborhood's gone."

His wife, Kim Woods added, "The whole neighborhood just to the north of us is pretty flattened."

Dhaval Naik, who said he works with the man whose house was demolished, said three people, including a child, were in the basement when the tornado hit. They got out safely.

KETV-TV video showed one woman being removed from a demolished home on a stretcher in Blair, a city just north of Omaha.

Omaha Police Chief Todd Schmaderer said there appeared to be few serious injuries, in part because people had plenty of warning that storms were likely.

The exact link between tornadoes and climate change is hard to draw. Here's why

"We not upon by a sudden storm," Schmaderer said. "People had warnings of this and that saved lives."

The tornado warning was issued in the Omaha area on Friday afternoon just as children were due to be released from school. Many schools had students shelter in place until the storm passed. Hours later, buses were still transporting students home.

Another tornado hit an area on the eastern edge of Omaha, passing directly through parts of Eppley Airfield, the city's airport. Officials closed the airport to aircraft operations to access damage but then reopened the facility, Omaha Airport Authority Chief Strategy Officer Steve McCoy said.

Severe weather damage to Eppley Airfield in Omaha, Neb., can be seen from the Lewis and Clark Monument in Council Bluffs, Iowa on Friday Anna Reed/Omaha World-Herald via AP hide caption

Severe weather damage to Eppley Airfield in Omaha, Neb., can be seen from the Lewis and Clark Monument in Council Bluffs, Iowa on Friday

The passenger terminal wasn't hit by the tornado but people rushed to storm shelters until the twister passed, McCoy said.

Flight delays are expected Friday evening.

After passing through the airport, the tornado crossed the Missouri River and into Iowa, north of Council Bluffs.

Nebraska Emergency Management Agency spokesperson Katrina Sperl said damage is just now being reported. Taylor Wilson, a spokesperson for the University of Nebraska Medical Center, said they hadn't seen any injuries yet.

Before the tornado hit the Omaha area, three workers in an industrial plant were injured Friday afternoon when a tornado struck an industrial plant in Lancaster County, sheriff's officials said in an update on the damage.

The building just northeast of the state capital of Lincoln had collapsed with about 70 employees inside and several people trapped, sheriff's officials said. Everyone was evacuated, and three people had injuries that were considered not life-threatening, authorities said.

Sheriff's officials say they also had reports of a tipped-over train near Waverly, also in Lancaster County.

Two people who were injured when the tornado passed through Lancaster County were being treated at the trauma center at Bryan Medical Center West Campus in Lincoln, the facility said in a news release. It said the patients were in triage and no details were released on their condition.

The Omaha Public Power District reported that nearly 10,000 customers were without power in the Omaha area.

Daniel Fienhold, manager of the Pink Poodle Steakhouse in Crescent, Iowa, said he was outside watching the weather with his daughter and restaurant employees. He said "it looked like a pretty big tornado was forming" northeast of town.

"It started raining, and then it started hailing, and then all the clouds started to kind of swirl and come together, and as soon as the wind started to pick up, that's when I headed for the basement, but we never saw it," Fienhold said.

The Weather Service also issued tornado watches across parts of Iowa, Kansas, Missouri, Oklahoma and Texas. And forecasters warned that large hail and damaging wind gusts were possible.