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Rare Water-Rich Mars Meteorite Discovered
astroengine writes "A rare Martian meteorite recently found in Morocco contains minerals with 10 times more water than previously discovered Mars meteorites, a finding that raises new questions about when and how long the planet most like Earth in the solar system had conditions suitable for life. The meteorite, known as Northwest Africa (NWA) 7034, is the second-oldest of 110 named stones originating from Mars that have been retrieved on Earth. Purchased from a Moroccan meteorite dealer in 2011, the black, baseball-sized stone, which weighs less than 1 pound, is 2.1 billion years old, meaning it formed during what is known as the early Amazonian era in Mars' geologic history. 'It's from a time on Mars that we actually don't know much about,' geologist Carl Agee, with the University of New Mexico in Albuquerque, told Discovery News."
Firstly, we probe for much much more than just water.
Secondly, we don't get more information from looking at a rock in Africa. We get some information, and it's different from the information we get from Mars itself.
Thirdly, this is from very early Mars history. It's very different to current Mars.
Or more super computers for New Mexico. Apparently they don't have nearly enough of them.
I'm put'n the trailer back on the rocket. It's time to colomonize me some mars!
Having to work for a living is the root of all evil.
How does someone become a meteorite dealer?
Without the money spent on probes (and, in particular, without the Apollo Lunar samples and the Viking Mars descent mass spectrometer), we wouldn't know that this was a Martian rock.
Does anyone else think they could have picked a better acronym for Africa than NWA?
The article is very short on explanations. For instance:
1/ When they say 'Martian meteorite' do they mean that it actually came from the surface of mars or rather than it's general origin was near to the orbit of mars?
2/ What guarantees are there that this rock is actually from mars?
3/ If so, how can you explain the parent meteor escaping the gravity well of mars? If this piece of rock is about a kilogram, then its entry mass must have been be quite large. The meteorite in California that was tracked with radar (the Sutton Mill's meteorite in 2008) and later collected had an estimated mass of 40,000 kg but only about 1 kg was recoverable from pieces much smaller than the one in the story.
4/ Following this, it would seem an improbable event that a/ there would be some impact on mars that would send ejecta as large as 40000 kg out of mars orbit and that b/ this orbit would be towards the earth. Any impact that could send ejecta into escape velocity would almost have to be tangential to the surface, and even then it is difficult to see how such an impact could even produce large ejecta as the impact would skim more across the surface rather than into the interior of the planet.
5/ usually dating of the material and its mineral composition leads to a supposition that it is of planetary origin. And yet this rock has a different material composition than martian rocks, as per the article. Thus it seems that the entire hypothesis that it came from mars should actually be questioned instead of inferring that mars had more water than because of the composition of this meteorite.
Just how can they actually prove that the rock came from mars? It seems Occam's razor needs some sharpening.
I remember not long ago that they were saying that the Corvid meteoroids were ejecta from the Giordano Bruno impact. This was proven false: http://adsabs.harvard.edu/abs/1993JGR....98.9145H
1. How do we know that a rock is from Mars, especially when its composition is different from what we've found on Mars to date.
Isotope ratios and certain element ratios. These depend on the history of a planetary body, and you can rule out every planet / asteroid but Mars. I always liked the conclusion in this paper :
There seems little likelihood that the SNCs are not from Mars. If they were from another planetary body, it would have to be substantially identical to Mars
Of course, there is no such other Mars in the solar system.
The existence and composition of little atmospheric inclusions (i.e., tiny little bits of Martian air trapped in the rock) were another convincing piece of evidence for the Mars meteorites, as was the evidence of alteration by water.
2. How do rocks leave Mars' gravity well in the first place? Are they shrapnel from Mars being hit by big meteorites?
In a way. Suppose you have a big meteor hit (the size of the one that formed the Baringer Meteor Crater, or bigger). The meteor drills into the body and goes beneath the surface. At some point, it is stopped, and it dumps its kinetic energy into the body of the planet (i.e., for big impacts the meteorite explodes at depth). The shock wave is roughly spherical, and so the part directed upwards lifts up the surface above where the meteorite hit. Most of this material is lifted not much more than the depth of the explosion, forming the characteristic lip of the crater, and typically turning the layers in the rock upside down at the lip. Some of this material can be accelerated to much higher velocities, however, forming (for example) the rays of the new craters on the Moon. If the meteorite is really big, some of the surface material is accelerated to escape velocity and away it goes. After a little while (a few dozen to no more than a million years), some material will hit another planet. Mars and Earth have been trading material like this for the life of the solar system.
The really amazing thing is that some of the material ejected is not treated too roughly. Spores and seeds etc. could definitely survive the trip.
We spend billions on probes, and get more information from looking at a rock in Africa.
Nice work NASA.
I imagine if we probed your ass we'd discover a passaage all the way across the Milky Way, perhaps?
sounds a little BS to me
"and you can rule out every planet / asteroid but Mars"
where is this catalog of every single asteroid to ever come close to earth since creation of earth?
The list of asteroids with an atmosphere and liquid water is rather short (as in, non-existant). That also rules out Venus and Mercury. The isotope data rules out the Earth (or the Moon). These arguments also rule out the Jovian satellites and stuff further out. Conversely, other isotope data make it clear these objects do come from within the solar system somewhere.
This was all argued out at length in the 1980's and there were many skeptics, but they were eventually convinced. I remember being at a debate in Paris where one of the leading skeptics was reduced to saying that, although these came from a body very much like Mars, and not like any other solar system body, that didn't prove they are from Mars. That was about when he lost me. Now, this is regarded as well established and not controversial at all.
"At some point, it is stopped"
yea when its out of energy genius
It has to get vaporized first.
In other news, Martian authorities report that a rare Earth meteor has been discovered to contain 10 times as much fissionable material as found in previous Earth meteorites. The finding calls into question previous assumptions within the scientific community that Earth may contain little fissionable material and therefore was deemed unlikely to support life. Still, some Martians are asking tough questions: "How do you know it came from Earth? Where's your proof? How do we know you're not just trying to save your precious space budget when we have more important things to worry about, like climbing out of the so-called Fiscal Crater?"
We spend billions on probes, and get more information from looking at a rock in Africa.
Nice work NASA.
I imagine if we probed your ass we'd discover a pasaage all the way across the Milky Way, perhaps?
Or at least to Uranus.
It must have been something you assimilated. . . .
We spend billions on probes, and get some complementary information from looking at a rock in Africa.
It's a bit like asking why we sent the Viking landers when we can see it's red from here.
systemd is Roko's Basilisk.