Curious Kids: does the Sun spin as well as the planets?
- Written by Belinda Nicholson, Lecturer, University of Southern Queensland
Curious Kids is a series for children. If you have a question you’d like an expert to answer, send it to curiouskids@theconversation.edu.au You might also like the podcast Imagine This, a co-production between ABC KIDS listen and The Conversation, based on Curious Kids.
Does the Sun spin as well as the planets? - Max, Ebony, Calissa, Daniel, Mason, Jewels, Ever, Ludah, Tyler, Finbar, Enda, Riley, ages 5 - 8, Australia.
Yes, the Sun absolutely spins.
In fact, everything in the universe spins. Some things spin faster than the Sun, some are slower than the Sun, and some things spin “backwards”.
How did the Sun start to spin? Well, when the Sun was born, it formed from a big cloud of swirling gas. This gas fell inwards and began to tighten into a ball shape to form the star. The small swirling motion turned into a lot of swirling motion and gave the Sun its spin.
And here’s another interesting Sun spin fact: the middle part of the Sun - its equator – spins more quickly than the top and bottom parts, which are called the Sun’s poles. It can do that because the Sun isn’t solid, it’s a ball of gas.
Read more: Curious Kids: how is the Sun burning?
When it was young, the Sun spun fast – very fast. It would do one rotation in a just a few Earth days.
But as it got older, the Sun slowed down. Now it spins once every 25 days at the equator and once every 35 days at the poles. That means we have to wait for nearly a month to go by here on Earth before most of the Sun finishes one complete spin.
The reason it slowed down is hard to explain, but it’s got to do with its magnetic fields. When it was young and hyperactive, Sun spun fast and had a super strong magnetic field. This big magnetic field dragged through space, acting like a brake and slowing the Sun down. The slower spin then made the magnetic field much smaller too, so today the Sun is slowing down by only a very little bit.
Have you ever heard of a pulsar? That’s what’s left when a huge star dies. They spin super fast. In fact, they can do one whole rotation in a fraction of a second.
How do we know that? Well, pulsars shoot out a big beam of energy and we can pick up a flash of that beam as it goes past, rotating like this lighthouse light, only faster.
The flashes of energy from the pulsar go past very fast and very often, so we know it is spinning incredibly fast.
So as you can see, lots of things in space are spinning. Our galaxy, the Milky Way, is also spinning.
With all of this spinning, why don’t we get dizzy? Humans have evolved here so we are used to the spinning, but if everything stopped spinning (which is not likely to happen) we would really feel it!
Read more: Curious Kids: What's going to happen to the Sun in the future? Will it explode?
Authors: Belinda Nicholson, Lecturer, University of Southern Queensland
Read more http://theconversation.com/curious-kids-does-the-sun-spin-as-well-as-the-planets-119877