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Can a spacecraft accelerate to or near the speed of light and if so if there were a human on board and it traveled 10 light years and came back to Earth how many years would have passed on Earth?
DJRehab
Though light is ever so slightly slower, there is almost no difference between the speed of light in a vacuum and it's speed in our atmosphere. The speed of light in our atmosphere is something like 99.97% of the speed of light in a vacuum.
Wiki User
∙ 15y ago
Wiki User
∙ 14y agoTrick question!! We start with the given that no one can accelerate to the speed of light. Ignoring that: one hour will have passed on earth. When traveling at exactly the speed of light, there is no passage of time, so the traveler would not be able to gauge when to stop the trip. There would be no way to set a timer or other mechanism on the ship to do this, since anything and everything accompanying the traveler occupies a frame of reference in which time is not passing. So someone on earth would have to measure the hour, and that's the hour that would pass. To the traveler the trip would feel as if it didn't even happen. The time spent at light speed would pass instantaneously for her/him. Answer According to Einstein's Special and General Theories of Relativity, it would be impossible for you to travel at the speed of light because, as you approach the speed of light, c, your mass increases until it becomes infinite at the speed of light and therefore it would take an infinite amount of energy to reach that speed. Therefore, no object with mass can ever attain the speed of light. In addition your length in the direction of travel shortens to zero, and the passage of time slows until it stops. However, should you accelerate near the speed of light and stay there in orbit for an hour, and if I assume that you mean an hour your time, then, as your time has slowed down, whilst an hour passes on your space ship, a considerably longer period of time elapses on earth to someone observing you. Depending upon your speed, this could be anything from one hour and a fraction of a second, to billions of years. This is known as the famous 'twin' paradox as postulated by Einstein. If a twin goes off in a spaceship travelling even half the speed of light, and returns to earth hoping to meet with his twin again, he will find his brother either old or dead of old age, as, to the twin accelerating away from earth, time aboard the ship will slow down in comparison with that on earth. This effect has been proved by space missions that have taken atomic clocks into space that had a synchronised comparison clock left on the earth. On the return of the ship it was found that its clock had slowed down by a fraction of a second (as the ship did not reach anywhere near light speed so the effect was small) - an amount exactly as Einstein had predicted by his equations.
Wiki User
∙ 11y agoThe answer would depend on how CLOSE the spacecraft came to lightspeed, and how quickly it could accelerate. The math is somewhat involved, and is related to the inverse square of the difference between lightspeed (abbreviated "c") and the speed of the spacecraft. So a spaceship which maxes out at .90*c will experience some time dilation, while a spacecraft that gets to 99% of c will experience a LOT of time dilation.
If a spacecraft could accelerate to .99999999999c for five years of "ship time", stop and then return at the same speed, the Sun itself would have grown old and died.
However, the answer to the first part of the question is "not by any means we know of." The fastest spacecraft currently (and for the foreseeable future) is Voyager 1, which has a speed relative to the Sun of about 17.3 kilometers per second. This is pretty fast, but light is about 17300 times faster than that; it's all well and good to talk about 0.9c, but we're still dabbling around at about 0.00006c.
Wiki User
∙ 13y ago8 minutes 32 seconds at the speed of light
Wiki User
∙ 14y agoLess than a minute. But that is not likely to happen; apparently it ain't possible to travel faster than light.
Wiki User
∙ 13y agoTime slows down by a factor of 1 / square root of 1- (v2 / c2), where v is the velocity (or speed) of the object, and c is the speed of light.
Wiki User
∙ 6y agoAt the speed of light, a photon will take about 8.3 minutes (500 seconds) to reach Earth
Wiki User
∙ 9y agoLight, traveling at the speed of light, traverses the space
between the sun and the Earth in 81/3 minutes.
Wiki User
∙ 14y agoappoximately 8 minutes
Wiki User
∙ 13y ago2.71 years (rounded)
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Is it true that Earth's gravitational pull on a spacecraft is greater as the spacecraft moves away from Earth?
False. The attractive force of gravity decreases with the square of the distance.
What was the first American spacecraft carrying an astronaut to orbit Earth?
The first American spacecraft which orbited the earth was called The Mercury Friendship 7, and the astronaut was a famous person his name was John Glenn, he was a senator for many years later.
What do astronauts fly in?
Astronauts in their spacecraft (such as the Space Shuttle) are lifted into space by huge rockets which accelerate the craft to "escape velocity" (about 25,000 mph). This puts the craft into orbit around the Earth, its forward velocity balancing the continuous pull of gravity. When they are ready to return to Earth, they use rockets to slow down, and gravity pulls them back out of orbit. When astronauts travelled to the Moon, another smaller rocket pushed the Apollo spacecraft out of orbit, and carried it to the gravitational field of the Moon. Another rocket firing pushed the craft back to Earth. Unmanned space probes have travelled to even farther distances from Earth, including the outer planets Uranus and Neptune. Most of the travel is coasting, because there is practically no matter in space to slow a spacecraft down.
The similarities between an aircraft and a spacecraft?
the both fly and have a streamlined shape.
Why does a spacecraft does not burns when it move from earth to space but it burns while returning from there?
When a spacecraft goes into space its speed increases dramatically once it leave the earths atmosphere. When it is returning to earth, it hits the atmosphere at a faster rate than it was traveling when it left. The friction of the atmosphere against the craft, heats it up.
What spacecraft traveled back and forth between earth and space?
Space shuttles
How many days does it takes to get to the moon from the earth?
At the speed the Apollo spacecraft traveled, it took three to three and a half days.
Where did john glenn traveled?
John Glenn traveled around the earth in a spacecraft. On February 20, 1962, Glenn flew the Friendship 7 mission becoming the third American in space and the first American to orbit the Earth circling it three times.
How fast did Apollo spacecraft travel when going to the moon?
The Apollo spacecraft traveled at a maximum speed of 24,000 mph. To overcome the Earth's gravitational pull, one must travel at or above its escape velocity which is 24,000 mph.
What are parasol used for in space?
Gigantic sails can be used as sun-jammers to propel spacecraft. Unlike a parasol on earth, which is used to block the sun's rays, these contraptions are designed to capture solar radiation and use the radiation energy to accelerate spacecraft.
If a spacecraft travels from earth to the edge of the solar system what will happen to the gravitational pull between earth and the spacecraft?
The gravitational pull between earth and the spacecraft will become insignificant.
What spacecraft landed on Neptune?
No spacecraft from Earth has ever landed on Neptune.
How does Gravity affect astronouts in space?
Gravity from objects such as the Earth, the Moon, the Sun, or the Milky Way will attract and accelerate an astronaut. "Accelerate" implies that the astronaut's velocity will change over time.If the astronaut is in free fall (basically, the spaceship's engine is not pushing the spacecraft), then the astronaut won't FEEL such gravity.
What spacecraft did John Glenn fly in to orbit the earth?
the Friendship 7 spacecraft
How does gravity affect the launch of spacecraft from earth?
It prevents the spacecraft from being launched as gravity causes it to be attracted towards earth.
Is it true that there is a spacecraft on its way to earth?
No.
What spacecraft studied earth?
a doctorinmay
