Should Mars be Terraformed?

[Odin]

Originally posted by Ned
Yeah, maybe it collapsing for its last time and we will share the fate of Mars.

I think science needs to take a hard look at what's going on to happen and see whether we can do anything about it.

BTW, I liked the movie Core. But I don't see how we could send a craft to the center of the earth.

We will have a magnetic field as long as we have a liquid outer core. Living things have gone through reversals THOUSANDS of times over the past 3.9 billion years with no ill effects, why start worrying now.

[Ned]

Heres more on an upcoming Odyssey mission. It includes package called Marie that will measure harmful radiation at the surface. Here is quote from Nasa's site.

"Mars is substantially exposed to the harshest elements of space weather. Unlike Earth, which sits inside a protective magnetic field called the magnetosphere, Mars does not have a global magnetic field to shield it from solar flares and cosmic rays. Another factor is the lack of atmosphere. Mars’ atmosphere is less than 1% as thick as Earth. These two factors make Mars vulnerable to space radiation. The Marie instrument was designed to measure the amount of harmful radiation in the Mars environment.

The radiation particles which are harmful to humans falls mostly in the energy range of 15 Me V to 500 MeV per nucleon. These are the particles with enough energy to damage human DNA. Some of the particles with 500 MeV/n and above pass through the human body so quickly there is not enough time to transfer their energy into the surrounding tissue. The Marie instrument is designed to measure particles in the range of 15 MeV to 500 MeV/n. The data gathered is combined into an energy spectrum which tells the story of how many particles at what energy level were present."

http://marie.jsc.nasa.gov/main.html

[Sava]

Sure, but I'm sure spacesuits have sufficient protection. There's no doubt that a naked Sava in space would get cancer. But I'd probably die from decompression or get frozen solid before that.

[Ned]

Originally posted by Odin


We will have a magnetic field as long as we have a liquid outer core. Living things have gone through reversals THOUSANDS of times over the past 3.9 billion years with no ill effects, why start worrying now.

Really? We survived, but the field reversals were short - a matter of weeks. What happens when they last 1,000 years? Who knows what happens then. Perhaps the only things that survived were fish living in the protected ocean and animals that lived in caves. Who knows. I haven't seen any studies on this.

The data from Mars suggests that even there that 1.5 years is tolerable, assuming the data pans out as expected. But longer?

[Ned]

Originally posted by Sava
Sure, but I'm sure spacesuits have sufficient protection. There's no doubt that a naked Sava in space would get cancer. But I'd probably die from decompression or get frozen solid before that.

Sava, NASA is planning, I believe, to generate powerful local magnetic fields using nuclear reactors. I can see these protecting the spacecraft on the way to Mars, and a base. But what about exploring vehicles on the surface?

Man, we are really going to have to come up with some neat inventions to put nuclear reactors on Mars cars.

[Sava]

Data from Mars? There were humans on Mars?

[Sava]

Man, we are really going to have to come up with some neat inventions to put nuclear reactors on Mars cars.

I want a Nukemobile!

[Ned]

Here is a summary from the Mar. 13 Odyssey report:

"Odyssey has measured radiation levels at Mars that are substantially higher than in low-Earth orbit. "The martian radiation environment experiment has confirmed expectations that future human explorers of Mars will face significant long-term health risks from space radiation," said Dr. Cary Zeitlin, principal investigator for the martian radiation environment experiment, National Space Biomedical Research Institute, Houston. "We've also observed solar particle events not seen by near-Earth radiation detectors."

http://mars.jpl.nasa.gov/odyssey/newsroom/pressreleases/20030313a.html

[Odin]

I highly dought the reversal will take 1000 years. I tust Discovery Mag with my science news thank you.

[Ned]

I don't see NASA allowing astronauts to go to Mars only to be killed or worse from the radiation, even if some think that 1.5 years can be "tolerated."

[Ned]

Originally posted by Odin
I highly dought the reversal will take 1000 years. I tust Discovery Mag with my science news thank you.

What did Discovery Mag. have to say?

[Odin]

Originally posted by Ned
What did Discovery Mag. have to say?

I was just questioning the credibility of your sorce.

[Straybow]

Lunar space suits are bulky gadgets designed to provide radiation protection. Astronauts were able to move easily in Lunar .16 gee gravity. The current design is lighter, but spacewalks are conducted in LEO well below the Van Allen Belts providing the bulk of protection against solar wind and flares.

As for reversals, these processes aren't as "clockwork" as some suggest. The statistical distribution is almost certainly a c² or similar weighting that isn't intuitively assessed as easily as a Gaussian. A 250k average could easily allow a 1000k interval around 2s (the upper 10% probability).

If Earth did enter a reversal transition we'd get nifty aurorae at all lattitudes. Other than that, duration and effects are a big unknown.

[yavoon]

why is it almost certainly x^2? and I dont remember it being a 250k avg. I remember being "every 250k years"

certainly if there is valid sources for this its all good. but if its just conjecture then why bother?

[Ned]

Originally posted by Straybow
Lunar space suits are bulky gadgets designed to provide radiation protection. Astronauts were able to move easily in Lunar .16 gee gravity. The current design is lighter, but spacewalks are conducted in LEO well below the Van Allen Belts providing the bulk of protection against solar wind and flares.

As for reversals, these processes aren't as "clockwork" as some suggest. The statistical distribution is almost certainly a c² or similar weighting that isn't intuitively assessed as easily as a Gaussian. A 250k average could easily allow a 1000k interval around 2s (the upper 10% probability).

If Earth did enter a reversal transition we'd get nifty aurorae at all lattitudes. Other than that, duration and effects are a big unknown.

Since it is not whether there will be a reversal, the question is how soon. It could happen "anytime" in the next 1000 years. The idea that the process is gradual is belied by the examples of weeks for a reversal to complete.

The next question, is what will be the effects on earth.

Since no one really knows the answer, we need someone to start finding out now.