When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Light-year - Wikipedia

    en.wikipedia.org/wiki/Light-year

    A light-year, alternatively spelled light year (ly or lyr [3]), is a unit of length used to express astronomical distances and is equal to exactly 9 460 730 472 580.8 km, which is approximately 5.88 trillion mi.

  3. Speed of light - Wikipedia

    en.wikipedia.org/wiki/Speed_of_Light

    A light-year is the distance light travels in one Julian year, around 9461 billion kilometres, 5879 billion miles, or 0.3066 parsecs. In round figures, a light year is nearly 10 trillion kilometres or nearly 6 trillion miles. Proxima Centauri, the closest star to Earth after the Sun, is around 4.2 light-years away. [89]

  4. List of nearest stars - Wikipedia

    en.wikipedia.org/wiki/List_of_nearest_stars

    This number is likely much higher, due to the sheer number of stars needed to be surveyed; a star approaching the Solar System 10 million years ago, moving at a typical Sun-relative 20–200 kilometers per second, would be 600–6,000 light-years from the Sun at present day, with millions of stars closer to the Sun.

  5. Astronomical unit - Wikipedia

    en.wikipedia.org/wiki/Astronomical_unit

    Distance of the outer limit of Oort cloud from the Sun (estimated, corresponds to 1.2 light-years) — Parsec: 206 265 — One parsec. The parsec is defined in terms of the astronomical unit, is used to measure distances beyond the scope of the Solar System and is about 3.26 light-years: 1 pc = 1 au/tan(1″) [6] [61] Proxima Centauri: 268 000 ...

  6. Solar System - Wikipedia

    en.wikipedia.org/wiki/Solar_System

    To a good first approximation, ... Within 10 light-years of the Sun there are ... to calculate the average Earth–Sun distance as 93,726,900 miles (150,838,800 km ...

  7. The first test of two-way laser communication occurred in December 2021 when NASA’s Laser Communications Relay Demonstration launched and went into orbit about 22,000 miles (35,406 kilometers ...

  8. Astronomers Found the Ancient Light Source That Literally ...

    www.aol.com/astronomers-found-ancient-light...

    This is the first time that these galaxies have been imaged in such detail, and the first time scientists were able to confirm that they produced enough radiation to end the light-less tyranny of ...

  9. Alpha Centauri - Wikipedia

    en.wikipedia.org/wiki/Alpha_Centauri

    The distance of Alpha Centauri from the Earth is now reckoned at 4.396 light-years or 4.159 × 10 13 km.) α Centauri A (left) is of the same stellar type G2 as the Sun, while α Centauri B (right) is a K1-type star. [67] Later, John Herschel made the first micrometrical observations in 1834. [68]