What is the reason why we have seasons on the Earth? Give as much detail as you can in your own words, but be careful…if you include a misconception, the score is 0.
We observe a distant object in space and see that the spectral lines for hydrogen in the object’s light appear at a shorter wavelength than normal. What does this tell us about the object and why? What is this effect called? Give as much detail in your own words as you can.
0 comments