2. Numero 1 The sun is about 150 million kilometers from earth. How long does it take light from the sun to reach earth? (The speed of light is 3x10 8 m/s.)

3. Question 2 The horsehead nebula in Orion is 1500 light-years away; the Andromeda galaxy is 2 million light- years away; the most distant quasars are over 10 billion light- years away. Is it possible to know what these objects look like right now? Why or why not?

4. Nombre 3 A light year is a unit of distance, the distance light travels in one year. How many kilometers long is a light-year?

5. Answers 1. t = 8.3 minutes 2. No, it takes a long time for that light to reach us. 3. 1light-year = 9.5 x 10 12 km