In Fact It’s Cold As Hell: Mars Isn’t As Earthlike As It Might Look

[n2doc]

“Mars ain’t no kind of place to raise your kids; in fact it’s cold as hell” sang Elton John in “Rocket Man”, and although the song was released in 1972 — four years before the first successful landing on Mars — his weather forecast was spot-on. Even though the fantastic images that are being returned from NASA’s Curiosity rover show a rocky, ruddy landscape that could easily be mistaken for an arid region of the American Southwest one must remember three things: this is Mars, we’re looking around the inside of an impact crater billions of years old, and it’s cold out there.


Mars Exploration Program blogger Jeffrey Marlow writes in his latest “Martian Diaries” post:

Over the first 30 sols, air temperature has ranged from approximately -103 degrees Fahrenheit (-75 Celsius) at night to roughly 32 degrees Fahrenheit (0 Celsius) in the afternoon. Two factors conspire to cause such a wide daily range (most day-night fluctuations on Earth are about 10 to 30 degrees Fahrenheit). The martian atmosphere is very thin; with fewer molecules in the air to heat up and cool down, there’s more solar power to go around during the day, and less atmospheric warmth at night, so the magnitude of temperature shifts is amplified. There is also very little water vapor; water is particularly good at retaining its heat, and the dryness makes the temperature swings even more pronounced.

In that way Mars is like an Earthly desert; even after a blisteringly hot day the temperatures can plummet at night, leaving an ill-prepared camper shivering beneath the cold glow of starlight. Except on Mars, where the Sun is only 50% as bright as on Earth and the atmosphere only 1% as dense, the nighttime lows dip to Arctic depths.


Read more: http://www.universetoday.com/97369/in-fact-its-cold-as-hell-mars-isnt-as-earthlike-as-it-might-look/

[a geek named Bob]

1. so we terraform it...

takes a long time, and we need to coordinate rock strikes...

Not impossible.

[moobu2]

5. It wouldn't work because Mars has no molten liquid iron core.

On Earth the molten iron core generates a magnetic field which protects it's atmosphere from cosmic rays and the planet from ultraviolet radiation. Everything would be cooked without it. They would have to find some mechanism to restart the core of Mars otherwise it will always remain a dead lifeless planet.

[a geek named Bob]

6. Okay...

that gives me a challenge.

[qazplm]

8. well that wouldn't affect the ability

to make the planet warmer in the short term.

And we wouldn't need the entire planet protected from radiation, just the parts we want to live on.

[Humanist_Activist]

11. Actually the Ozone layer protects the surface from UV radiation...

the Ozone layer being formed by free Oxygen Molecules(O2) interacting with Cosmic Rays in the upper atmosphere, creating Ozone(O3).

What an active magnetosphere is useful for is protecting us from some high energy cosmic rays and the solar wind from the sun. The rest is the atmosphere protecting us, many cosmic rays are absorbed by the molecules present in the atmosphere.

A terraformed Mars would have a much thicker atmosphere, hence a buffer from most harmful radiation. Free oxygen in its atmosphere would naturally form an ozone layer in its upper atmosphere, just like on Earth. The lack of a magnetosphere may pose a different problem, it appears that the atmosphere of planets, at least in the inner solar system, wear away because of the solar wind, unless constantly replenished. This looks to have been what happened to Mars.

What this means is if we do thicken the atmosphere of Mars, it won't "stick" as it were, but will erode into space, being blasted away, slowly, by the solar wind, so would require replenishing.

"The Core" isn't a documentary, if, for example, our magnetosphere collapsed today, we would mostly notice it in some electrical disruptions, compasses not working properly, auroras in odd places, but mostly it would mark the beginning of an erosion of our atmosphere. We wouldn't cook, we wouldn't die immediately, and the time scales of the erosion would be in thousands of years.

[liberal N proud]

2. Lots of room for global warming

[n2doc]

3. It has been suggested

Crash some water, methane and CO2-rich asteroids into Mars until it gets warm enough.

Of course this is science fiction, for now.

[struggle4progress]

4. It seems, however, that one must then do that continually, since the gravity of Mars

is inadequate to hold any significant atmosphere for long

[NickB79]

13. "For long" in geological terms is still probably millions of years

I've actually read studies that found we could terraform the Moon and it's gravity would hold a breathable atmosphere for 10,000 years. A blink of an eye in geological terms, but twice as long as human civilization to date.

[a geek named Bob]

7. Not true

Mars has enough gravity to hold an atmosphere. It's just question of getting it there.

[lastlib]

9. But it would have to be continually replenished....

...because the solar wind will strip it away.

Lacking the strong magnetic field to deflect the sun's particle bombardment, Mars simply cannot long hold an atmosphere that can sustain life.

[a geek named Bob]

10. So we add in belts of satellites that build mag shields...

Not gonna quit on this one...

[sakabatou]

12. If we can't terraform it

We could build build structures in space and then send it to Mars.