What great questions you have!! These were some of the questions scientists asked and only just answered in the past hundreds of years.

The answer about the Sun is tricky because first I have to ask you to think about the Sun a little different than you think about it right now. The Sun is moving through space with lots of other stars that are far far away. But compared to Earth, it mostly stays in one place in space and Earth moves around the Sun, like horses moving around the center post of a carousel. Gravity is what ties Earth and the Sun together and Earth is moving in such a way that it will not "fall" into the Sun. If Earth did "fall" into the Sun, from our perspective on Earth it would look to you and I like the Sun falling out of the Sky. Luckily we don't expect this to happen so the Sun will always "stay up in space."

Another perspective is that we sit on Earth and see the Sun giving us daytime and disappearing at night - it rises and sets every day. But what actually happens is that Earth rotates on its axis - like a ballerina doing a piroutte. But we are on one place on the Earth and as Earth turns, we move into daylight and then out of it again.

For both of these answers, it would very much help to have a globe of Earth to show what we are talking about. Perhaps, Mrs. Martin can do a demonstration of some of these concepts!

The Sun is all different colors, but it is the brightest in the yellowish-green color and this is why many children's book show the Sun as yellow. Because it is brightest in yellow, we call it yellow. But it also has red, blue, ultraviolet, infrared... and many more colors.

Laura

Thank you SO much. My class was SO excited to get the response from a real scientist. We did the globe demonstration too. We really appreciate your time :).

Hi Mrs. Martin's 2nd grade class!

Your first question is a tricky one to answer because it seems to assume that everything in space would fall to Earth if it weren't being held to space by some force. But this way of thinking is only true close to Earth. One we travel out away from Earth, things no longer fall towards Earth, but will fall towards other things with gravity. Also, things with more stuff pushed together, like the Sun, will pull other things with less stuff towards it. So in fact, the Sun is always pulling Earth towards it. But Earth is moving in a circle around the Sun, so the Sun's pull can never get it to come closer - just like spinning around in a circle with a yo-yo at the end of a string. You are pulling the yo-yo towards you using the string, but you are spinning so the yo-yo just goes in a circle instead of crashing into you. The same thing happens with the Sun and Earth. The Sun is pulling Earth as Earth spins around the Sun. The string is called 'gravity' and is invisible. So the Sun uses gravity to pull Earth and Earth goes in a circle so it never goes into the Sun - just around and around the Sun. The Sun travels out in space with Earth orbiting around it and so it looks like the Sun is staying up in space but really, Earth is staying 'up in space!'

Your second question is a bit easier! The Sun's light is brightest in the green color. But because all the colors from red to purple coming from the Sun come out almost at the same brightness, we can also say that the Sun is white. The Sun appears yellow in part because the only time our eyes can kind of glimpse at the Sun (never look directly at the Sun!), it is usually near the horizon. There is so much atmosphere that the light has to pass through that the atmosphere scatters the blue light, making the Sun look yellow.

You asked some tough questions, so I hope these answers make sense. Ask if you have more questions and we can try and help you understand it all!

Laura