Naked Science Forum

General Science => General Science => Topic started by: @mykie213 on 04/04/2011 16:30:03

Title: How long could we live without the Sun?
Post by: @mykie213 on 04/04/2011 16:30:03

@mykie213 asked the Naked Scientists:
   
Hi, if the sun was to just stop burning, how long would we have to live here on earth?,

love the show (http://www.thenakedscientists.com/HTML/podcasts/)!, thank you.
What do you think?

Title: How long could we live without the Sun?
Post by: GlentoranMark on 04/04/2011 19:45:52

I'd hazard a guess of only seconds unless we had a source of heat. Everything would simply freeze solid.

Title: How long could we live without the Sun?
Post by: CliffordK on 04/04/2011 21:08:04

Quote from: GlentoranMark on 04/04/2011 19:45:52

I'd hazard a guess of only seconds unless we had a source of heat. Everything would simply freeze solid.

Most of us can survive the night without the sun.

Based on the day/night temperature differences, I would guess that we could loose about 5°C or 10°F a day (or more) for the first couple of weeks.

Humans would survive as long as our energy and food supplies would last.  But within a few weeks the devastation would be be tremendous. 

Food chains would collapse around the planet.

Geothermal heat vent extremophile bacteria would survive for quite a while.  Many seeds and spores would go dormant and might survive in a dormant state for several decades, perhaps a few centuries until DNA degraded enough that recovery would be impossible.

Some isolated pockets of humans would likely be able to maintain non-solar power sources including geothermal, wind, and nuclear, and convert to grow lights for crops.  Perhaps humans would rebuild underground dwellings to utilize geothermal energy sources.  However, the number of survivors beyond a year or so would be only a small fraction of a percent of the population at the onset of the problem.

Title: How long could we live without the Sun?
Post by: GrapperJ on 08/04/2011 18:08:33

Quote from: @mykie213 on 04/04/2011 16:30:03

@mykie213 asked the Naked Scientists:
   
Hi, if the sun was to just stop burning, how long would we have to live here on earth?,
What do you think?

The earth's surface would become unlivable within a matter of weeks due to the extreme cold. The temperature on the surface of the outer are around –355 degrees Fahrenheit. The earth's surface temperature would rapidly dive to that inhabitable temperature.

Geothermal heat from the earth will continue independent from the sun's existence so it would be possible to maintain a livable subterranean habitat . Geothermal electricity generation would also still be possible and because of that, food could be grown underground using artificial lights. Since geothermal energy will be around for a long long time, I think it would be theoretically possible for humans to live indefinitely if proper preparations were made.

I say indefinitely, because if geothermal did eventually die out, humans could transition into uranium/thorium nuclear reactors and eventually into fusion (if discovered/possible).

Title: How long could we live without the Sun?
Post by: Madidus_Scientia on 09/04/2011 13:25:00

Quote from: GlentoranMark on 04/04/2011 19:45:52

I'd hazard a guess of only seconds unless we had a source of heat. Everything would simply freeze solid.

In addition to, as CliffordK points out, surviving the night without the sun, we would be able to survive at least the 8 minutes it takes for the light (and lack of light) to reach us from the sun.