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A 2001 space odyssey indeed! On this day in 2001, the Mars Odyssey spacecraft launched, and now, 3,333 days later, the robotic spacecraft is still going strong. In orbit around the Red Planet, Mars Odyssey has collected more than 130,000 images and continues to send information to Earth about Martian geology, climate, and mineralogy. Last December, Mars Odyssey broke the record for the longest-serving spacecraft at Mars, besting the Mars Global Surveyor, which operated in orbit of Mars from 1997 to 2006.
Measurements by Odyssey have enabled scientists to create maps of minerals and chemical elements and identify regions with buried water ice. Images that measure the surface temperature have provided spectacular views of Martian topography.
Early in the mission, Odyssey determined that radiation in low-Mars orbit is twice that in low-Earth orbit. This is an essential piece of information for eventual human exploration because of its potential health effects — Odyssey has provided vital support to ongoing exploration of Mars by relaying data from the Mars rovers to Earth via the spacecraft’s UHF antenna.
Odyssey will support the 2012 landing of the Mars Science Laboratory and surface operations of that mission. Mars Science Laboratory, a.k.a Curiosity, will assess whether its landing area has had environmental conditions favorable for microbial life and preserving evidence about whether life has existed there. The rover will carry the largest, most advanced set of instruments for scientific studies ever sent to the Martian surface.
Mars Odyssey carries three main science instruments: The Gamma Ray Spectrometer (GRS), the Thermal Emission Imaging System (THEMIS), and the Mars Radiation Environment Experiment (MARIE).
More info: Mars Odyssey website, THEMIS website (tons of great images)
Mars is a bit further than one and a half times as far as Earth is to Sol @1.5 A.U. and yet “…radiation in low-Mars orbit is twice that in low-Earth orbit.”
We’d all be ‘toast’ without our beautiful magnetic field to shield us from harsher rads.! I’m quite thankful for that, but may be verging on a ‘blasphemous’ subject even mentioning it? But thanks Supreme Being, for thy electric presence!
Somehow, an Amen seems appropriate here.
I suggest swearing by “Goodness” as a way of swearing, affirmation, expressing hope… etc… which is not loaded or biased and should be acceptable to most proponents and opponents of various belief systems and theories… 😉
Actually what is causing most radiation problem of Earth LEO is the Van Allen belts of the geomagnetic field. And what is shielding inhabitants from radiation, whether solar of cosmic, is our atmosphere.
An atmosphere will generally leak faster with a weaker field, since it shields from CMEs that may stand for 2/3 or more of leakage (~ 2/3 on Earth, AFAIU).
But in Mars case I have read that the magnetic field remnants may accelerate its leakage from various processes. Also, the heavy carbonate and extensive ice layers unveiled now points to geological deposition as the historical primary remover, AFAIU.
And in Venus case it still holds “too much atmosphere”, without having much of a magnetic field (due to exceedingly slow rotation).
So, you may keep or lose a geomagnetic field, whether it is useful for protection may be locally decided. (Though in general it should be beneficial.)
Now you can make a case for the heliospheric field, that shields from ~ 90 % of cosmic rays IIRC. But that is a balance with the same CMEs that threatens our atmosphere blowing up the heliosphere.
In no way are magnetic fields the prime movers here, or always beneficial. What protects us is the atmosphere. And, considering the EU/PU bullshit paraded around here as if it was of any physics importance, that is a gas. 😀
Actually, even the founder of Universe Today Frasier Cain thinks its the Earth’s magnetic field that protects us from harmful radiation! A quote in part from his article published March 12, 2009 entitled: Earth’s Magnetic Field
“You can’t see it, but there’s an invisible force field around the Earth. Okay, not a force field, exactly, but a gigantic magnetic field surrounding the Earth, and it acts like a force field, protecting the planet – and all the life – from space radiation.”
http://www.universetoday.com/27005/earths-magnetic-field/
“But in Mars case I have read that the magnetic field remnants may accelerate its leakage from various processes.”
Which processes exactly? My understanding is that without a magnetic field to repel charged particles coming from the sun and other stars the atmosphere is essentially blown away. Indeed our atmosphere protects us, but what would protect our atmosphere with no magnetic field?
I’d love to understand this better though,
E
I’m enjoying NASA and the entire extra-planetary research industry, both National and Private’s remarkable track record, especially of late, for both launch success and average mission longevity…