Exploring Mars will be a risky business
Are humans ready to stay on Mars for several months? Can we deal with all the risks that its environment may cause to astronauts and space missions? Red Nova says that some answers are contained in a report from NASA. According to this report, the #1 risk is Martian dust because it can potentially damage power systems, space suits and filtration systems. So NASA wants to launch a space robotic mission to bring back to Earth a sample of at least one kilogram of Martian dust to evaluate how chemically toxic it is.
The Red Nova focuses on Murphy's law and here is how it introduces it.
According to Murphy's Law, whatever can go wrong, will go wrong, and presumably this applies on Mars as well as Earth. So if things go wrong on Mars, are we ready for them? What do we need to know about Mars before we send people there?
Some of the answers are contained in a report from NASA's Mars Exploration Program Analysis Group (MEPAG) published in June 2005 and titled "An Analysis of the Precursor Measurements of Mars Needed to Reduce the Risk of the First Human Mission to Mars." Here is a link to this report (PDF format, 77 pages, 1.66 MB, June 2005).
The heart of MEPAG's June report is a full-page table on p. 11 that lists 20 risks, "any one of which could take out a mission," says David Beaty, Mars Program Science Manager at the Jet Propulsion Laboratory, and the report's lead author.
Here are some of the major risks by decreasing priority.
- Is Martian dust toxic and dangerous?
- Are there organisms dangerous for humans living on Mars?
- How Martian dust storms can affect space missions during landings and takeoffs?
- Is there water available if astronauts stay for more than a year?
But there are other risks as well.
For example, take the Galactic Cosmic Radiation (GCR), which is a continuous, low-dose source of charged particles -- because . And a chronic exposure to GCR might have "late" effects that might only be detected years or decades after a space mission, such as an increased cancer risk.
Below is a "Mars radiation globe calculated"with the NASA transport code HZETRN. The contribution from albedo neutrons is not included. The color-coded scale is in units of Sieverts per year (Credit: NASA).
If you want to know what is a Sievert, here is a link to its definition by Wikipedia. In short, the sievert attempts to reflect the biological effects of radiation as opposed to the physical aspects. And one sievert is equal to 100 rems, a more common unit of radiation, but which is no longer a SI unit.
Here are more details about Martian dust from the Red Nova article.
Loud and clear from the MEPAG report is that "Martian dust is a #1 risk," says Jim Garvin, NASA chief scientist at the Goddard Space Flight Center. "We need to understand the dust in designing power systems, space suits and filtration systems. We need to mitigate it, keep it out, figure out how to live with it."
This is why a robotic mission to Mars is absolutely essential before sending humans to the red planet.
Scientists and engineers simply need to get their hands on real Martian dirt. The significance of a sample even as small as 1 kilogram "should not be underestimated" for both its scientific and engineering value, Beaty adds.
And for more information about a future human mission to Mars and its associated risks, please read the full METAG report, or jump to its conclusions which you'll find on pages 63 and 64.
Sources: Red Nova, October 30, 2005; and various NASA's web sites
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