

However, the space shuttle doesn’t go that fast all the time. In order to stay in space orbit, the shuttle must reach a speed of 28,000 km / h. Its successor, the Apollo 11, reached tremendous speeds at times but traveled at an average speed of 5,000 km / h. Such speed is still not possible to reach with today’s technology. When returning from lunar orbit, their spacecraft reached a speed of 39,897 kilometers per hour. Apollo 10 was a test mission just before sending a man to the Moon. The human speed record was set by astronauts during the Apollo 10 mission. The speed at which we will travel in space depends on the spacecraft we use. One parsec is equal to 3.3 light years or 31 trillion kilometers. It is used to measure the distance between celestial bodies located outside the Solar System. There is even a unit that is larger than a light year, and that is the parsec. The distances in space are becoming so great that it is impractical to express them in common units of measurement, so we turn to light years. When we hear the term light year, we immediately think of time, but a light year has nothing to do with calculating the year. There is no difference in the length of the light year and human year.Ī light year is just a name used for a unit of distance, not time. One light year is therefore the same as one human year. How many days is a light year in human years?Ī light year is used to calculate the distance that light travels in a human year. One Julian year, the year how we measure it, has 365.25 days, or 31,500,000 seconds. The speed of light is 299 792458 meters per second. It would be a bit complicated to use kilometers or miles to measure distances in space given that the distance between certain celestial bodies would require numerous zeros.

This unit of measurement is used primarily in astronomy to calculate the distance between celestial objects. It is assumed that there are no strong magnetic or gravitational fields at this distance.

How long is a light year?įirst thing you need to know: a light year is a unit of measurement for distance, not for time! It is a unit of distance that represents the total distance that the beam of light travels in one year moving in a straight line in empty space. A journey lasting one light year or a billion light years for a person traveling at the speed of light will seem absolutely the same in time. For an object traveling at the speed of light, time is irrelevant. On Earth, we have learned to count time in seconds, minutes, hours, days and years. The difference in the experience of traveling one light year occurs due to different perceptions of time on Earth and in space. Time stops for a man, as does his aging, as long as his spacecraft travels at the speed of light.įor people on Earth, however, the journey of one light year would take one year. In spacecraft, time would pass differently, so one would not even have the feeling of traveling and the travel time would fly by in less than a second. To travel one light year, if we travel at the speed of light, it would take us one year. How long would it take to travel one light year? We can easily determine how long it takes us to cover a certain distance in kilometers if we know how fast we are going, but we never calculate how long it takes us to travel a light year. In space, it is easier to measure distance with the help of light years. The universe is so large, that sometimes measuring in kilometers or miles is pointless. On Earth, we measure distance through steps, meters, kilometers, miles, or some other unit of measurement by which we can determine distance.
