because light only travels to us at light speed, and so the light that gets to us is reflecting off of things as they were x years ago. If a star is 4 light years away, then the star that we see is the star as it was 4 years ago, because the light from the star took 4 years to reach us. So we are looking into the past.
We see objects in space as YOUNGER than they really are. The reason being, while light is very fast, it still takes many, many years to get from another star to Earth. Thus, the light we see is several years old and only shows the star how it was those years ago.For example, Arcturus, one of the brightest stars in the night sky is about 36 or 37 light years away. This means it takes light from Arcturus 37 years to reach the Earth. So when you see Arcturus in the sky, you're seeing it how it was 37 years ago, not necessarily in this moment.
The Sun's light rays reflect off the Moon and the light enters our eyes and we can see the Moon.We see the Sun because the light rays reflect off the Sun into our eyes.We see the stars the same way as we see the Sun
You can see the Moon and most stars with your eyes. It's pretty easy if you aren't actually blind. However, you should use a solar filter to look at the Sun. Otherwise you can end up blind.The Sun and other stars shine because they are hot. This is worth understanding in detail. The Moon and planets shine with reflected light. The Moon, in particular, is about as bright as asphalt, which is not very much. This is worth understanding in detail.
The sun and other stars make their own light through the process of fusion. The moon and planets are seen by the sunlight reflecting from them.
Refracting telescopes depend on one amazing fact. As light passes through glass, it slows down. Slowing down a light beam makes it bend. Why? Imagine you’re pulling a wagon along a sidewalk, when the wheels on one side slip off into the grass. The wheels turn slower in the grass than they do on the sidewalk, and...