Research Suggests Mars Once Had a Thick Atmosphere 98
astroengine writes "At one time, Mars had a thick, protective atmosphere — possibly even cushier than Earth's — but the bubble of gases mostly dissipated about 4 billion years ago and has never been replenished, new research shows. The findings come from NASA's Mars rover Curiosity, which has been moonlighting as an atmospheric probe as it scours planet's surface for habitats that could have supported ancient microbial life. 'On Earth, our magnetic field protects us, it shields us from the solar wind particles. Without Earth's magnetic field, we would have no atmosphere and there would be no life on this planet. Everything would be wiped out — especially when you go back 4 billion years. The solar wind was at least 100 times stronger then than it is today. It was a young sun with a very intense radiation,' Chris Webster, manager of the Planetary Sciences Instruments Office at NASA's Jet Propulsion Laboratory in Pasadena, Calif., told Discovery News. Unfortunately for Mars, the last 4 billion years have not been kind."
Planetary magnetic field (Score:5, Interesting)
Are we sure of that? While I can accept that Mars lost its atmosphere due to the solar wind stripping it, it should also be noted that Venus has a very weak magnetic field, yet it has a far larger atmosphere than the Earth. In fact, most of the magnetic field of Venus comes from the solar wind interacting with the atmosphere.
Once again I'll say it (Score:5, Interesting)
Another idea (Score:4, Interesting)
I believe Mars was once equal to Earth: Dense enought atmosphere, oceans of water on the surface, and even a magnetic field protecting the atmosphere. But, some day long, long ago this [wikipedia.org] happened, and caused the equivalent of Armageddon on the planet and turned him into what we know today. A "killed" planet.
Re:Terraforming Mars (Score:5, Interesting)
Think of a planet like a giant centrifuge. Smash the two planets together and you'll create enough heat that you'd end up with a massive molten mass. Have the hit be 'off center' and you'll impart a huge amount of kinetic motion. Between gravity and centrifugal forces the heavier elements like iron will tend to end up towards the center while spinning, thus creating your magnetic field.
How can you resist? (Score:4, Interesting)
Mars is trapped in its orbit and will remain there for the foreseeable future. It will still be there once we have developed the new energy solutions we need on this planet.
What application is demanding the development of new energy solutions? Right now ALL OF OUR EGGS ARE IN ONE BASKET. Solving the extinction problem should be priority #1. You call yourself Sentient?! Get your ass to Mars. Damn, we can't be ANY more blunt than that! The dinosaurs! Think!
So, here you are, with a space program. You've got a HUGE fabulous moon that's easy to see and get to that's got the same chemical composition of your planet, and a nice deep crater at the south pole to hang out in from solar storms. The next planet out has more gravity but has no magnetic field or atmosphere, but it's got resources you can use... PERFECT trial grounds for learning how to survive in deep space. Beyond that, there's a huge asteroid field with abundant resources for building things in space without the gravity tax, including Ceres a dwarf planet made of ice and rock... Ice = water = hydrogen & oxygen... grrrrr. Next we have a HUGE Gas Giant to study gravitational effects without getting burnt by the sun. In the solar system you just happen to find yourself in there are beautiful ringed worlds further out, and There's ice moons and moons full of methane, and... And... AND.
calm, stay calm...
And this puny minded ape wants to JUST SIT THERE?! You let defected pieces of shit like this survive among you?! You'll NEVER solve the Fermi Paradox at this rate!
Re:Terraforming Mars (Score:5, Interesting)
Assuming an Earth-sized planet in Venus orbit, even at its very closest, it would only accelerate the Earth at about 3 mm / s^2. If we can manage to move Mars and Mercury to collide with Venus in such a way that all material is maintained by Venus, such a minute effect on our orbit is meaningless. But since we're dreaming up unicorns, let's move Mars to be a moon of Venus instead. Then we can terraform both and have a nicely habitable double planet.
Atmospheric Loss? (Score:4, Interesting)
This article seems to be alluding to the solar wind stripping Mars's atmosphere away. Wasn't there just a study a few months ago showing that the effects of solar winds on a planetary atmosphere are not nearly as significant as was once believed, and that there is almost no way that the solar wind alone could be responsible for the Martian atmospheres losses. Personally I'd trust that data a lot more as I think it was based on current measurements of the effects of the solar wind on the Martian atmosphere, not extrapolations from microscopic amounts of materials found in Martian meteorites that likely went through extreme events getting here (being blown off of Mars, spending years, decades, centuries and even eons in space, and then atmospheric reentry) that could have altered their chemistry. My two cents on the whole thing is most of the Martian atmosphere is probably still on Mars, tens, hundreds or even thousands of miles below the surface. Most people don't conceive of how narrow a margin we cling to life on this spinning ball of mud floating on a sea of lava. If you took a basketball and laid a single sheet of paper on its surface that width is far more than the area in which humans can survive without supplemental support systems. As the planets interior cooled the atmosphere may have retreated into the crust, on Earth this is prevented the elements in question (water, nitrogen, oxygen) tend to be ejected by Earths interior in a variety of ways (geysers, volcanoes, fissures) because of their tendency to expand when they come into contact with heat. On Mars as the planet cooled the atmosphere could have leaked through fissures and permeable areas in the crust as the internal temperatures were no longer able to keep it near the surface. This could open interesting possibilities for colonization, as to retrieve significant amounts of atmosphere, water and other necessary components future colonists may only need to sink "wells" deep enough to reach those deposits. Microbial life may even have followed these life sustaining elements into the planets crust as they retreated over the eons.
Re:Planetary magnetic field (Score:3, Interesting)
This is an unconvincing argument. Hydrogen would escape into space without the solar wind. And free oxygen is not a normal thing. It required life for it to be released on the Earth (from CO2). And as far as the high concentrations of CO2, the Earth has methods to store it as limestone which makes Venus look more extreme than the Earth even though the actual total carbon levels are similar. Thus, the inference that Earth couldn't have life without geomagnetism is still not conclusive in my opinion.