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Phoenix Mars Lander Deploys Robotic Arm, Possibly Finds Ice
The Phoenix Mars Lander has successfully deployed its robotic arm and tested other instruments including a laser designed to detect dust, clouds, and fog. The arm will be used to dig up samples of the Martian surface, which will be analyzed as a possible habitat for life. A camera on the arm will allow pictures to be taken of the ground directly beneath the lander. The camera has already seen what may be ice, which was exposed when the soil was disturbed by the landing. The data collected by the arm will be compared to recent findings which suggest that water on Mars may have been too salty for most known forms of life.
The rovers can't dig as deep, nor could they have survived more than a season at these polar latitudes either. There isn't as much ice (or for that matter, any ice that we've been able to find) at the latitudes where the rovers are operating.
As for what we already have on Mars, we have rovers that have amazingly gone almost 10km each. That's about 1% of the distance they'd have to cover to get to where this one is. So in terms of "what we have on mars" that "are capable of finding out what the polar ice caps are like", we currently had nothing until Phoenix.
"The scientists say that the handful of terrestrial halophiles -- species that can tolerate high salinity -- descended from ancestors that first evolved in purer waters. Based on what we know about Earth, they say that it's difficult to imagine life arising in acidic, oxidizing brines like those inferred for ancient Mars."
Looks like it is just very unlikely with what we know.
The take multiple images with different filters in front of the lens then create a composite of these images to generate a approx. color image.
Additionally they use color patterns on the probes body to calibrate the color generation based on the known color of the patterns (American flag, etc. on Phoenix). They need this because of the way that sun light is affected by the martian atmosphere (which can vary based on local conditions).
Because other than the "gee, that's pretty" factor, a color image doesn't have as much significance as a grayscale image that has been taken through specific filters. The probe has multiple filters so they can take images that are sensitive at different wavelengths (depending on what they want to "see").
If they want a standard color image, they can take three pictures with R, G, B filters and combine them. It's not like anything they're (likely) going to take a picture of is going to move anyway, so taking 3 sequential images won't be a problem.
Grayscale images are also smaller (bandwidth-wise) so they can transmit faster. No use wasting time transmitting a larger image if your camera is pointed at the wrong thing.
The supposed salinity of the water on Mars is much higher than any halophile could survive.
great idea, since water vapor accounts for like 80%-90% of greenhouse gases.
NASA is the catalyst behind much of the research and development in areas that might help solve this problem you are so worried about.
Fuel Cells, Solar Technology, and a better understanding of the Sun and it's fission come to mind.
Planetary geology, atmospheric science, agriculture (thanks for the weather satellites and accurate maps of the Earth guys) gee I could go on.. all these things are directly beneficial to humanity and the quest of sustaining our existence on this planet.
I just can't fathom how anyone thinks planetary science and exploring space is pointless intellectual drivel. Wow.
I took a course with Steve Squyres (the principal investigator for the rover mission) in the fall semester. According to him, you can't look to Earth extremophiles as evidence that life can arise in these conditions. Extremophiles apparently all have adaptations such that, inside their cells, they can do their chemistry in 'normal' (non-acidic, non-salty, ...) conditions. If life were to arise in extreme conditions, they'd probably need totally different chemistry.
There's certainly a possibility of some exotic form of life arising in extreme (for us) conditions, but we shouldn't be expecting it to be possible, as there's no evidence that it can happen.
It's the first successful landing that used retrorockets since the Vikings (IIRC) in the 70s. All other retrorocket-based landings have failed. The rovers used airbags.
Yes. The chances of destroying life that can withstand extremely high radiation levels, a virtual vacuum, and living in frozen C02 is unlikely to be bothered by a little bit of ammonia steam for a few seconds. Additionally the design intentionally spreads the plume over a wide area to lower the local heating, pressure, or contamination effects. Melting ice isn't likely given the small heat input and short duration, but it's not clear that melting a little bit of ice for a few seconds before it refreezes actually hurts anything much.
Brett
You state that as if it were a fact, rather than the opinion it actually is.
They aren't saying conditions are good for life based on what we consider habitable. They saying conditions are good for life based on the laws of physics and chemistry and reasonable extrapolations from the same.
Yes. The retrorockets are designed to produce minimal contamination and/or disturbance. (And they shut off a couple of meters above the ground to further reduce the effects.) The arm is designed to dig down well below the expected penetration level of any contamination or disturbance.
Which is the attitude that's killing NASA. When you need 10s of billions of dollars from an intellectually disinterested tax base, "gee, that's pretty" can sell your ideas and pay the bills. I'm not saying sell out, but try to make the science more accessible.
I swear to God...I swear to God! That is NOT how you treat your human!