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Why is the sun a star if stars shine at night? Why is the sun the only star during the day?
Question Date: 2020-08-24
Answer 1:

Well, first off, the Sun is a star like the billions upon billions of other stars in the Milky Way galaxy that we live in. By the way, the Milky Way galaxy is only one of almost a Trillion other GALAXIES!

In fact the Sun appears different only because it is so close to us.

The light the Sun emits at its surface (photosphere actually since the Sun does NOT have a surface you could stand on) takes 8 minutes to reach us travelling at the speed of light. The NEXT nearest star to Earth is called Proxima Centauri and light from THAT star takes four years to reach us!

Now many of the stars you can see on a clear night all night long (the circumpolar stars of our latitude) are still “out there” during the day. You can’t see them because the Sun is so bright. It would be like you facing a car at night with its HIGH BEAMS on shining right in your face. Now, if someone siting in the car in addition shined a flashlight towards you, you would not be able to realize that… the high beam auto lights would make that impossible!

The Sun actually is fixed in the sky and its motion across OUR sky is called apparent motion. That is the Sun sets each day because the Earth is spinning and the spin carries everyone into the sun at local dawn and away from the sun at local sunset. Just do a simple experiment:
Take a ball and have a friend stand away from you and rotate the ball on its up/down axis while you shine a flashlight at the globe. At any given instant half the globe is getting light and the other have is in darkness; this is why we don’t see the Sun 24/7.

However, now imagine a star that is far, far away and sits along the projection of the Earth spin axis… then that star will never set or use since the spin of the Earth will never block its light from reaching us. A good example is the North Star, a star called Polaris.

Now you should make the following observation TONIGHT after dark if it is clear: Go outside and point yourself towards the North (use a compass or your iPhone!) Then look up about 35 degrees above the North Horizon. You should be able to spot the North Star.

Good luck.

Answer 2:

Hi Khloe, this is a great question! Stars come in a lot of different shapes and sizes throughout the galaxies in our universe. The important distinction about the sun is that it is our star; simply put, it's the closest one and it provides the energy and heat to keep the earth functioning in harmony.

The nuclear reactions that happen within the core of the sun produce a gargantuan amount of energy and light that is emitted in every direction. When the part of the Earth that you stand on is facing the sun, it is day for you as the light from the sun outshines all other sources of light because it is so much closer than any other stars. It is night when your part of the Earth faces the opposite direction. Many of the stars that you see at night are the same as the sun but are light years away. That distance makes them look like just a speck in the sky at night.

Answer 3:

All stars shine, all the time. We can't see the sun at night only because it's on the other side of the Earth, so our view of the sun is blocked. This is why when it's day time in Santa Barbara, it will be night in Calcutta (a city in India), and when it is night in Santa Barbara, it will be day in Calcutta.

The sun is really close to Earth, close enough that it takes light about eight minutes to reach the Earth from the sun. The next-closest start to Earth, Proxima Centauri, is so far away that it takes light a little over four years for light to get here. Four years is a lot longer than eight minutes!

Because the sun is so close, it looks really bright, so bright that it lights up the whole rest of the sky to the point that we can't see anything that isn't pretty bright. Other stars are so far away that they look really faint to us, too faint for us to see during the day, even though they're still there.

Answer 4:

Stars shine all night and all day. They're huge burning things. Our Sun is a star so close to us that it lights up the whole sky, and we can't see all the other stars. When it starts to get dark, we say, "The stars come out" - first, the brightest stars, and then dimmer stars, when the sky gets darker.

There's a famous science fiction story about a planet with 5 suns, and they only have a night every 2,049 years. Then civilization falls apart. The next night is due soon, and some people put their important things in a cave and trap themselves there, to see what night is like. They figure there are probably a few stars, besides their own; but they go crazy when they see thousands and thousands of other stars. It's called 'Nightfall' and it's by Isaac Asimov.

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