Alex Stephens Jnr wrote:

"Chris Handscomb" wrote in message
...

From a scientific viewpoint, what would happen if the sun just stopped
producing light and heat in an instant? What would happen on the day and
night sides of the Earth respectively? How long would it take for the

Earth

to freeze - what would the lowest temperature be? What would happen to the
weather systems in the atmosphere, how long would it take for life to

become

extinct? Would there still be electricity? For how long? Forgetting about
the social and political aspects of it?

Anyone want to be curious about this and give some answers?

Jeremy (not Chris)



Hi Jeremy,
A very strange question indeed.

It's an interesting, metaphorical question

The sun could never stop producing heat and light in an instant of course,
to do that it would have to vanish from existence and in that process (if it
were possible) it's mass would create vast amounts of energy. E=MC².

*BANG*

But let's suppose the mass of the sun could just vanish without trace. The
whole Earth would instantly be plummeted into perpetual night - no moonlight
or planets to see in the sky - just starlight. The planet would no longer
be bound in a gravitational orbit and would just travel freely through
space.

Not true. The Earth would still be bound by the gravitational effects of
the Moon, Jupiter, Saturn, Neptune, Uranus, Venus, Mars, Mercury, Pluto
and all the other bits of rock and gas in the solar system.

The instant effects would be vast I guess. On the surface the air would
rapidly cool down. Without solar energy, convection and evaporation would
cease within a few days. All water vapour would precipitate or condense out
of the sky, the air would cool very rapidly - then the land and seas.

It cools quickly enough at sunset and during eclipses!

Oceans would freeze within 2 weeks probably, then the very air we breathe
would condense out of the atmosphere and eventually freeze as solid Nitrogen
and Oxygen etc on the surface. I'm not sure of the timescale - but this
would all happen within a month I reckon.
The effects on the planet beneath the surface would be equally dramatic no
doubt.

The planet itself should retain a significant amount of heat I guess.
It's hot down there!

Forget about electricity or weather, they would disappear.

Electricity wouldn't disappear.

Gradually the earth would cool down to the temperature of empty space (3°K?
/ -270°C).

It would take a significant amount of time for this to happen fully; the
core temperature of the Earth would be retained for quite a while.

I'm sure a book could be written on the additional effects I've neglected.
I hope my glimpse into some of the possible effects sheds some light on
your question(s) anyway.

Yes. If anyone has access, I'm sure certain parts of this question have
been answered by The Last Word column in the New Scientist magazine.

Jonathan