1. Light - year is an astronomical unit.

2. Do you know the light year?

3. The outer disk contains unusual light-year long orange filaments.

4. A light-year is the distance light travels in one Earth year

5. Every stock market within a light year is arguing in your head.

6. The distance travelled by light in one year is called a light year.

7. And one light year is the distance that light travels in a year .

8. And one light year is the distance that light travels in a year.

9. The distance traveled by light in one year is called a light year.

10. Its bright ring with pearls of glowing gas is half a light-year across.

11. Know astronomical unit and light year are used for expressing the distance between celestial bodies.

12. * In a globular cluster, the stars are packed tightly, about one tenth of a light-year apart.

13. It spans about 000 light-years in diameter, compared to the Milky Way's 000 light-year diameter.

14. The light-month, roughly one-twelfth of a light-year, is also used occasionally for approximate measures.

15. The average separation between the stars at its centre is no more than a tenth of a light-year.

16. Within just a light-year of the black hole swarm more than 000 other stars caught far more firmly in its grip.

17. Scientists have already proposed that a hidden star, which they call 'Nemesis,' might exist a light-year or so away from our sun.

18. About a light-year across, the ring material itself was likely shed by the star about 000 years before it went supernova, according to HubbleSite.

19. The object is actually a shell of gas and dust that has been blown off by a faint central star, lying around 700 light-year away in the constellation of Aquarius.

20. By 2011 debris in the center of the ring, which is about a light-year in diameter, was blazing more intensely as the supernova entered a new stage of stellar demise.

21. None of those planets are like Gliese 581 g, a rocky world about three times the mass of Earth orbiting -- along with five sibling planets -- a red dwarf star 20 light-year from Earth.

22. Clues might include the high 1000-kilometer per second speed of the expelled gas, the light-year long length of the structure, and the magnetism of the star visible above at the nebula's center.

23. Contents: The Infinite Assassin (1991) The Hundred Light-Year Diary (1992) Eugene (1990) The Caress (1990) Blood Sisters (1991) Axiomatic (1990) The Safe-Deposit Box (1990) Seeing (1995) A Kidnapping (1995) Learning to Be Me

24. This is an illustration of how the night sky might look to a dweller in the core of galaxy NGC 42 which harbors an 800-light-year-wide disk of dust and 2 billion-solar-mass black hole.