What is a light-year and how is it used?? - NASA
What is a light-year. and how is it used? Answer: A light-year is a unit of distance. It is the distance that light can travel in one year. Light moves at a velocity of about 300,000 kilometers (km) each second. So in one year, it can travel about 10 trillion km. More p recisely, one light-year is equal to 9,500,000,000,000 kilometers.
StarChild: Glossary - NASA
LIGHT YEAR The distance light can travel in one year, which is 9,500,000,000,000 kilometers. M MAGNETIC FIELD The area in which an attractive or repelling force exists between two magnets or in association with the element iron. The Earth's magnetic field is thought to be due to the liquid iron-nickel which is in its core.
Just How Big is this Place? - NASA
A light year is equal to 9,500,000,000,000 km and is the distance that light travels in one year. A light year can be expressed as 9.5 trillion km or in scientific notation as 9.5 x 10 12 km. The star outside of our solar system that is closest to Earth is Alpha Centauri C.
Does the Sun move around the Milky Way? - NASA
StarChild Question of the Month for February 2000 Question: Does the Sun move around the Milky Way? Answer: Yes, the Sun - in fact, our whole solar system - orbits around the center of the Milky Way Galaxy.
Parallax - NASA
Parallax. Astronomers derive distances to the nearest stars (closer than about 100 light-years) by a method called stellar parallax.
How long does it take to fly to Saturn? - NASA
StarChild Question of the Month for April 2002 Question: How long does it take to fly to Saturn? Answer: How long it takes to travel anywhere depends on how far you want to go and how fast you move.
StarChild: Galaxies - NASA
A light-year is the distance light travels in one year. It is 9.5 trillion (9,500,000,000,000) kilometers. The size of a galaxy may be as little as a thousand light-years across or as much as a million light-years across.
Where do comets come from? - NASA
StarChild Question of the Month for December 2001 Question: Where do comets come from? Answer: Comets are believed to have two sources.
StarChild: The Milky Way - NASA
The Milky Way is over 100,000 light-years wide. It is called a spiral galaxy because it has long arms which spin around like a giant pinwheel.
Letters Lost In Space Solution - starchild.gsfc.nasa.gov
EAGHILTYR = LIGHT YEAR . The distance that light travels in one year. LIGHT YEAR . A scientist who observes and studies planets, stars, and galaxies. ASTRONOMER . A group of millions or billions of stars, gas, and dust held together by gravity. GALAXY . The invisible force between objects that makes objects attract each other. GRAVITY