How long does it take light to cross the universe?

Answer 1

1 A.U.= 1.49597870 x (10 to the 11th power) metres. The speed of light = 299792458 metres / second. So t=1 A.U. divided by c = 499 seconds or 8 minutes, 19 seconds. An Astronomical Unit is a little less than the average distance between the sun and the earth.

Answer 2

Light can cross the observable universe in about 13.8 billion years, given the current estimate of the universe's age being about 13.8 billion years. This is because the observable universe has a radius of about 46.6 billion light-years.

Answer 3

about 100,000 years.

Not actually. I don't know the exact amount of time, but let me put something else into perspective.

If light were to travel from one end of our universe to the other, traveling at roughly 180,000 miles per second (or 300,000 kilometres per second), it would take about 10,000 years.

So in perspective, maybe like 100 years, maybe less.

Answer 4

An astronomical unit (AU) is the distance between the Earth and the Sun, and is set at 92,963,314.36 miles. The speed of light is defined as 186,282.397 miles per second. So dividing 1 AU by this speed gives a time of 499.0450835 seconds for light to cover that distance. Dividing this value by 60 gives a value of 8.317418058 minutes, or 8 minutes and 19 seconds.

Answer 5

(100 billion light years) x (5.8787 x 1012 miles per light year) = 5.8787 x 1023miles.

But wait! Don't go away disappointed. We know you posted this nonsense question on

WikiAnswers in order to see a big number, and we aim to please. So, here is the same

answer again, written this time in 'standard' form rather than scientific form.

100,000,000,000 light years = 587,870,000,000,000,000,000,000 miles (rounded)

There you are. A distance 7.7 times farther than the radius of the observable universe. How cool is that !

Answer 6

In order for a beam of light to cross the entire known universe, it would take somewhere between 30-36 billion years. However, in that time, the universe will have continued to expand faster than the light is moving, so the light will never reach its destination.

Answer 7

If you'll accept a rounded-off answer:

8.642 x 1022 miles

or

86,417,000,000,000,000,000,000 miles

or

Nearly the distance light has been able to travel in a vacuum since the big bang.

Answer 8

There are approximently 63,239.6717 Astronomical Units (AU) in a Light-year (LY).

Answer 9

1 Astronomical Unit = 8.3167464 light-minutes

Answer 10

The Milky Way is roughly 100,000 light years in diameter. So, observers would conclude that it takes light 100,000 years to make the trip.