Unfortunately, a Mars mission doesn't have the mass budget for that much radiation shielding, either during the cruise stage or on the planet (which still has a lot more ionizing radiation reaching the surface than Earth does due to the lack of a strong magnetic field + much thinner atmosphere; otherwise, the Odyssey gamma-ray and neutron spectrometers wouldn't work so well). The processors still have to be radiation-hardened.
Sexy doesn't always mean "big-breasted". People like Keira Knightley and Calista Flockhart have been on plenty of magazine covers.
I (for one) am always irritated when all the female avatars in games have super-sized breasts and hips, because I'd rather play one that looks realistically athletic. And yeah, I'm a straight woman.
BTW how do you know that the "girls" you meet in MMOs are actual girls? Just wondering.
Martian rock *is* rusty, but it is not carbonaceous. A major goal of the MGS TES instrument (see for example http://tes.asu.edu/) was to look for carbonates, but they never found any. *Small* amounts of carbonates (less than 1 percent) can be found in Martian meteorites, but not enough to be useful.
The major reservoir of CO2, as other posters have pointed out, is in the seasonal polar ice, although a lot of the permanent ice cap is water ice. If you warmed Mars, you'd have more CO2 in the atmosphere, since it wouldn't freeze out over the winter pole anymore.
Asteroids generally do not have a lot of solid gases on them! Maybe you're thinking of comets? Occasionally people propose that some asteroid or other is actually an extinct comet nucleus, and there's some reason to think that the largest one (Ceres) might have some subsurface frozen volatiles or something, but your run-of-the-mill asteroid is rocky or occasionally metallic. Crashing one into the surface of Mars will not add gases to the atmosphere...
Instead of Ayn Rand, perhaps some actual economics books might be more helpful? I'd recommend the taped lecture series "Contemporary Economic Issues" by Timothy Taylor. (Many public libraries carry these.) Even if you don't agree with all his conclusions, he does a good job of giving a big-picture view of the last ~50 years in the economy of the US and several other regions so you can make up your own mind.
That's a pretty good summary, but people should know that Mars has twomoons. However, they're not nearly as big as Earth's moon and are probably captured asteroids, not the result of a giant impact, so they don't invalidate this theory.
They're going to try for a high-latitude landing again, but this time in the northern hemisphere. The Mars Phoenix lander is scheduled for 2008. You can read more about it here: http://phoenix.lpl.arizona.edu/objectives.php
You don't need to find water, you can make it with Hydrogen and Oxygen. There's a LOT of Oxygen in the moon's crust, and very likely a good amount of Hydrogen in the regolith deposited by the solar wind.
There isn't a lot of free oxygen. There
are a lot of oxygen atoms in the minerals that
make up the rocks and soil, but in order to make
water out of it you'd have to overcome some fairly
large binding energies. It's the same problem
you'd have with making water out of rocks on
Earth. There's a reason people in the middle
of the desert aren't getting oxygen out of the
sand in order to make water for themselves -- it
takes a lot of energy. Sure, if you wanted to
throw enough solar panels or a nuclear reactor
at the problem, you could do it, but the question
is, how much energy would you have to put in
per liter of water?
The hydrogen from the solar wind is a separate
issue -- it's not that there are zero hydrogen
atoms implanted in the soil by the solar wind,
but how many acres of lunar soil would you have
to go through to collect a reasonable amount?
Lunar Prospector's neutron spectrometer was
sensitive to hydrogen, and IIRC came up with
extremely low concentrations except at the south
pole.
The US has tried to be careful about sterilizing
its Mars landers. The Viking landers were very
thoroughly sterilized, since their main purpose was
to look for signs of life; it was important to
eliminate false positive results from terrestrial
"hitchhikers". The Pathfinder and MER landers were
mainly geology missions and that, combined with
the negative Viking results, led to a somewhat
lower standard of sterility. (IIRC they went over
the exterior of the rover with disinfectants, but
did not have to heat sterilize all the internal components.) According to this
interview:
"There is a set of international treaties and agreements that regulate the ability of us to take bacteria or organic material or spores to Mars in order to avoid contaminating Mars for future scientific investigations. The Mars Exploration Rover project is what is called a Class B. We're not involved in the search for life and so we have a level of cleanliness that we did when we put the rovers together. If you were a Class A mission looking more directly for life, the requirements would be much more stringent. You would actually have to sterilize the equipment, almost like an operating room, in order to be able to satisfy these agreements."
I'm curious about the extent to which the Soviet
Mars landers were sterilized. None of them
were exactly successful, but a couple made it to the surface and crashed there.
FYI I asked for a paper ballot today in the same state
as gmhowell, but they refused to give me one,
even though I gave essentially the same explanation
for why I didn't trust the touch screens.
Evidently it varies with the local poll workers.
There's still a lot of water ice at high latitudes,
though, not only in the above-ground polar caps
but underground in the surrounding terrains. In
fact we don't know how much, since the Odyssey
orbiter's gamma-ray/neutron instrument only
sees down to a couple of meters at best. There
could be tens of meters of buried permafrost
with a high (>70%) ice content up there. I
think it's too early to say what the remaining
global water inventory really is.
Do you know whether the various Soviet missions to
Mars were disinfected to the same standards? Many
of them failed before reaching Mars, but on this
list I count at least two that made it to the
surface before failure:
Yes, but the Earth's core is not a permanently
magnetized ferromagnet. It's a magnetic
dynamo. Google "planetary magnetic field" and
"dynamo" if you don't believe me.
Most naturally occuring iron deposits are not
enormous permanent magnets.
Actually the main reason why there's no magnetic
field is because the rotation period is too slow.
No matter how much iron and nickel
you have in the core -- no rotation, no dynamo.
I'm a girl. Legos were among my favorite toys and not because we built a lot of tea sets out of them. My sister and I built tons of stuff out of both the bricks and the specialized sets (mostly the castles but also airports and stuff).
We played with dolls too, but usually we equipped them with homemade swords and bows (parents didn't believe in buying us toy weapons, so we made them out of pipe cleaners) and pretended they were the queens of Amazon kingdoms. Boys weren't allowed, though, on account of cooties. We did get interested in boys eventually, but that was much later.
Anyway, I guess I'm saying (1) yes, girls play with Legos and (2) girls who play with Legos can also play with dolls, and you'd be surprised how un-"girlie-girl" dolls can be.
For example, a dip in neutron readings could also come from a simple lack of radioactive elements in that portion of the crust, though this is unlikely.
These neutrons are actually mainly created by cosmic-ray induced activity, not natural radioactivity, so a lack of radiogenic elements wouldn't really do much to the numbers.
For the same reason, you wouldn't get the same result from an orbiting neutron detector on Earth-- the Earth's atmosphere, being much thicker than the Martian atmosphere, intereferes with most of the cosmic rays before they can interact with the surface and produce neutrons.
The Outer Planets program is a specific program that is in charge of the Pluto and Europa missions. It does not include the missions you're thinking of (Galileo, Cassini, Voyager, Pioneer), although, confusingly, those missions did go to the outer planets.
As an aside, Galileo, Voyager, et al. are all powered by RTGs (Radioisotope Thermoelectric Generators), as were the Viking Mars landers. They wouldn't have been able to perform their missions at all without them, except possibly for Viking. If I'm reading the article correctly, these are the sorts of nuclear technologies that the administration plans to support. There's an informative page on them at this page [jpl.nasa.gov].
Re:How this impacts *my* company
on
Loki Games Closing?
·
· Score: 2, Informative
Please, please don't steer them toward Pine or Mutt. If pine had been my first linux experience,
I would have run away screaming. I mean, even techmail was more fun to use than pine. Meanwhile, Eudora (and presumably outlook, kmail, and evolution) will let you sort messages and
even view more than one email at a time. It's really hard to give that up once you're
used to it.
Seriously, you shouldn't be pushing free solutions that are less useful than the windows
or mac equivalents or of course people will conclude that free software is inferior, and
they may never try it again. Concentrate on the linux applications that actually do what they do better than the non-free competition. They're out there.
Slashdot Mirror
Unfortunately, a Mars mission doesn't have the mass budget for that much radiation shielding, either during the cruise stage or on the planet (which still has a lot more ionizing radiation reaching the surface than Earth does due to the lack of a strong magnetic field + much thinner atmosphere; otherwise, the Odyssey gamma-ray and neutron spectrometers wouldn't work so well). The processors still have to be radiation-hardened.
I (for one) am always irritated when all the female avatars in games have super-sized breasts and hips, because I'd rather play one that looks realistically athletic. And yeah, I'm a straight woman.
BTW how do you know that the "girls" you meet in MMOs are actual girls? Just wondering.
Martian rock *is* rusty, but it is not carbonaceous. A major goal of the MGS TES instrument (see for example http://tes.asu.edu/) was to look for carbonates, but they never found any. *Small* amounts of carbonates (less than 1 percent) can be found in Martian meteorites, but not enough to be useful.
The major reservoir of CO2, as other posters have pointed out, is in the seasonal polar ice, although a lot of the permanent ice cap is water ice. If you warmed Mars, you'd have more CO2 in the atmosphere, since it wouldn't freeze out over the winter pole anymore.
Asteroids generally do not have a lot of solid gases on them! Maybe you're thinking of comets? Occasionally people propose that some asteroid or other is actually an extinct comet nucleus, and there's some reason to think that the largest one (Ceres) might have some subsurface frozen volatiles or something, but your run-of-the-mill asteroid is rocky or occasionally metallic. Crashing one into the surface of Mars will not add gases to the atmosphere...
Instead of Ayn Rand, perhaps some actual economics books might be more helpful? I'd recommend the taped lecture series "Contemporary Economic Issues" by Timothy Taylor. (Many public libraries carry these.) Even if you don't agree with all his conclusions, he does a good job of giving a big-picture view of the last ~50 years in the economy of the US and several other regions so you can make up your own mind.
That's a pretty good summary, but people should know that Mars has two moons. However, they're not nearly as big as Earth's moon and are probably captured asteroids, not the result of a giant impact, so they don't invalidate this theory.
They're going to try for a high-latitude landing again, but this time in the northern hemisphere. The Mars Phoenix lander is scheduled for 2008. You can read more about it here:
http://phoenix.lpl.arizona.edu/objectives.php
Or catdoc will do it, even without starting Emacs. Text only though.
There isn't a lot of free oxygen. There are a lot of oxygen atoms in the minerals that make up the rocks and soil, but in order to make water out of it you'd have to overcome some fairly large binding energies. It's the same problem you'd have with making water out of rocks on Earth. There's a reason people in the middle of the desert aren't getting oxygen out of the sand in order to make water for themselves -- it takes a lot of energy. Sure, if you wanted to throw enough solar panels or a nuclear reactor at the problem, you could do it, but the question is, how much energy would you have to put in per liter of water?
The hydrogen from the solar wind is a separate issue -- it's not that there are zero hydrogen atoms implanted in the soil by the solar wind, but how many acres of lunar soil would you have to go through to collect a reasonable amount? Lunar Prospector's neutron spectrometer was sensitive to hydrogen, and IIRC came up with extremely low concentrations except at the south pole.
The US has tried to be careful about sterilizing its Mars landers. The Viking landers were very thoroughly sterilized, since their main purpose was to look for signs of life; it was important to eliminate false positive results from terrestrial "hitchhikers". The Pathfinder and MER landers were mainly geology missions and that, combined with the negative Viking results, led to a somewhat lower standard of sterility. (IIRC they went over the exterior of the rover with disinfectants, but did not have to heat sterilize all the internal components.) According to this interview:
http://www.ksc.nasa.gov/nasadirect/elv/merb/theis- ab.htm
"There is a set of international treaties and agreements that regulate the ability of us to take bacteria or organic material or spores to Mars in order to avoid contaminating Mars for future scientific investigations. The Mars Exploration Rover project is what is called a Class B. We're not involved in the search for life and so we have a level of cleanliness that we did when we put the rovers together. If you were a Class A mission looking more directly for life, the requirements would be much more stringent. You would actually have to sterilize the equipment, almost like an operating room, in order to be able to satisfy these agreements."
I'm curious about the extent to which the Soviet Mars landers were sterilized. None of them were exactly successful, but a couple made it to the surface and crashed there.
FYI I asked for a paper ballot today in the same state as gmhowell, but they refused to give me one, even though I gave essentially the same explanation for why I didn't trust the touch screens. Evidently it varies with the local poll workers.
There's still a lot of water ice at high latitudes, though, not only in the above-ground polar caps but underground in the surrounding terrains. In fact we don't know how much, since the Odyssey orbiter's gamma-ray/neutron instrument only sees down to a couple of meters at best. There could be tens of meters of buried permafrost with a high (>70%) ice content up there. I think it's too early to say what the remaining global water inventory really is.
http://www.russianspaceweb.com/spacecraft_planetar y_mars.html
Most naturally occuring iron deposits are not enormous permanent magnets.
Actually the main reason why there's no magnetic field is because the rotation period is too slow. No matter how much iron and nickel you have in the core -- no rotation, no dynamo.
We played with dolls too, but usually we equipped them with homemade swords and bows (parents didn't believe in buying us toy weapons, so we made them out of pipe cleaners) and pretended they were the queens of Amazon kingdoms. Boys weren't allowed, though, on account of cooties. We did get interested in boys eventually, but that was much later.
Anyway, I guess I'm saying (1) yes, girls play with Legos and (2) girls who play with Legos can also play with dolls, and you'd be surprised how un-"girlie-girl" dolls can be.
For example, a dip in neutron readings could also come from a simple lack of radioactive elements in that portion of the crust, though this is unlikely. These neutrons are actually mainly created by cosmic-ray induced activity, not natural radioactivity, so a lack of radiogenic elements wouldn't really do much to the numbers. For the same reason, you wouldn't get the same result from an orbiting neutron detector on Earth-- the Earth's atmosphere, being much thicker than the Martian atmosphere, intereferes with most of the cosmic rays before they can interact with the surface and produce neutrons.
The Outer Planets program is a specific program that is in charge of the Pluto and Europa missions. It does not include the missions you're thinking of (Galileo, Cassini, Voyager, Pioneer), although, confusingly, those missions did go to the outer planets.
As an aside, Galileo, Voyager, et al. are all powered by RTGs (Radioisotope Thermoelectric Generators), as were the Viking Mars landers. They wouldn't have been able to perform their missions at all without them, except possibly for Viking. If I'm reading the article correctly, these are the sorts of nuclear technologies that the administration plans to support. There's an informative page on them at this page [jpl.nasa.gov].
I would have run away screaming. I mean, even techmail was more fun to use than pine. Meanwhile, Eudora (and presumably outlook, kmail, and evolution) will let you sort messages and
even view more than one email at a time. It's really hard to give that up once you're
used to it.
Seriously, you shouldn't be pushing free solutions that are less useful than the windows
or mac equivalents or of course people will conclude that free software is inferior, and
they may never try it again. Concentrate on the linux applications that actually do what they do better than the non-free competition. They're out there.