1 : a unit of length in astronomy equal to the distance that light travels in one year in a vacuum or about 5.88 trillion miles (9.46 trillion kilometers)

The particle energy is calculated based on the mass and velocity. The particles does not show interference. The wave is defined as the propagating dynamic distrubance. The energy of the wave is calculated based on the wavelength and velocity.

Light behaves as a wave – it undergoes reflection, refraction, and diffraction just like any wave would. Yet there is still more reason to believe in the wavelike nature of light. Continue with Lesson 1 to learn about more behaviors that could never be explained by a strictly particle-view of light.

As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year (365.25 days). Because it includes the word “year”, the term light-year is sometimes misinterpreted as a unit of time….

63,241 astronomical units

Solution : Light year and wavelength both represents the distance, so both has dimension of length not of time.

For most space objects, we use light-years to describe their distance. A light-year is the distance light travels in one Earth year. One light-year is about 6 trillion miles (9 trillion km).

Answer. The distance that light travels in one year is called a light year. The speed of a light year travel is 3 x 108 meters in one second.

30 billion light-years away

This duration is a bit of a problem, as it makes space exploration a painstakingly slow process. Even if we hopped aboard the space shuttle discovery, which can travel 5 miles a second, it would take us about 37,200 years to go one light-year.

roughly 1,736,809 years

To do so, you will need a speed of almost the speed of light, so in the reference frame of Earth, you will have spent just a tad more that 1000 yr to travel 1000 ly. i.e. 1000 years, 4 hours, and 23 minutes in Earth’s reference frame.

It is as enourmous as 279 trillion kilometers or AU. You need to develop a Vehicle nothing less than 1/1000th the speed of light to transport to this gigantic distance it would take you minimum 31000 years.

The planet is so far away, spaceships travelling close to the speed of light would take 20 years to make the journey. If a rocket was one day able to travel at a tenth of the speed of light, it would take 200 years to make the journey.

First of all, a light-year is the distance light travels in one year. The star Alpha Centauri is about 4 light-years away, so light from Alpha Centauri takes 4 years to get to the Earth.