Expert: James Gort - 4/22/2005

Question
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Followup To
Question -
Have you ever been into space? If yes please discrab you exerinces and fealing about what you saw in space, Did you enjoy space? What do you think would happen when the earth stops rotaing? Is that possible?  
Answer -
Hello Becca,

No, I've never been in space.  But I did apply to the Canadian Astronauts Program.  Thousand of people applied.  I made it pretty far, but wasn't selected.  Would you like to apply to NASA some day?

Now, about the earth stopping to rotate-

The earth's rotation carries a LOT of energy, in the form of "angular momentum".  It gained that energy when the planet condensed from the gas and dust forming the early solar system.  To stop the rotation, something would have to somehow get rid of that energy (to stop it).

That's not impossible, but it's unlikely we could live through such an event.  In Uranus's early history, astronomers think it collided with a large body that changed its rotation.  It didn't completely stop it, but it knocked it on "its side".  So Uranus doesn't rotate from west to east, but from north to south!  I suppose if the body would have hit it somewhat differently (rapidly moving objects carry a lot of momentum), the direction of rotation of Uranus could have been totally stopped.

In the case of the earth, nothing internal (like earthquakes or magnetic poles changing) could totally stop the rotation (although a large earthquake slightly does change the axis of rotation).  But a collision with an earth-sized body could cause it to change its rotation, although that collision could also break up the planet, or otherwise make it uninhabitable.

If the earth stopped rotating, the days would get longer than 24 hours, until one side of the earth would always be day, and the other side would always be night.  But because the earth is tilted 23.5 degrees to its orbit, the extreme northern and southern hemispheres would still have days and nights, but they would each be about a year long.  Weather would become much more extreme (the sunlit side would become very hot, and the dark side very cold, although very strong winds would try to even it out a little).  Very little vegetation would grow on the dark side.  The earth would become a very much harsher place to live, and droughts would be common.  Many plants and animals would die, but humans would probably adapt and survive.

Hope that answers your question.  It can happen by a collision, but I know of nothing else that can cause it.

Prof. James Gort


Hey I rated you a 10 out of ten in everything. Your space adventure awnsers  
where exitent and fast. What is the Candian Astronuts Program about and like?  

Answer
Hello Becca,

The Canadian Astronaut's Program was set up by Canada to train Canadians for space travel.  Canada has done much in space.  It was the first country in the world to launch communications satellites (for T.V. and telephones), and still has the largest ones.

Canadians also invented the Space Arm used on the Shuttle so that other satellites could be grabbed and repaired.

Canadians now go into space regularly, if they were trained as astronauts.

Hope that helps.

Prof. James Gort