Slashdot Mirror
Mars Express Confirms Water on Mars
jki writes "So, finally: Through the initial mapping of the South polar cap on 18 January, OMEGA, the combined camera and infrared spectrometer, has already revealed the presence of water ice and carbon dioxide ice. This information was confirmed by the PFS, a new high-resolution spectrometer of unprecedented accuracy. The first PFS data also show that the carbon oxide distribution is different in the northern and southern hemispheres of Mars. The MaRS instrument, a sophisticated radio transmitter and receiver, emitted a first signal successfully on 21 January that was received on Earth through a 70- metre antenna in Australia after it was reflected and scattered from the surface of Mars. This new measurement technique allows the detection of the chemical composition of the Mars atmosphere, ionosphere and surface." On another note, NASA has gotten some sort of signal from Spirit, but it's still not fully functional.
It has been confirmed on the north pole before, but not the south. That's why it's news.
it's in my head
no, we knew that there was frozen carbon dioxide on mars (dry ice), but not water ice. we've believed there has been water on the planet at some point due to certain geographical and geological reasons (the way some of the rocks are pointing the same direction, the "canals", etc, etc), but we don't know for sure that there actually was water on the planet.
Looks like some telemetry was just received from Spirit:
http://www.jpl.nasa.gov/releases/2004/30.cfm
Actually, I believe the NASA discovery was at the North pole, though I agree that this news is not very groundbreaking.
BTW, does anyone know how they identified the North/South poles? Was a compass sent there in a previous mission, or was it an arbitrary decision?
/* This sig is disabled. Press CTRL-W to enable. Thankyou */
You must be from Japan ?s pacecraft/ tworovers_br.html
If the rover is the size of compact car, it is very compact !
Here are both the current rover and the previous one in the same picture:
http://marsrovers.jpl.nasa.gov/gallery/
One seat could barely fit.
according to the latest on NASA's marsrover webpage, an additional communication session of ~20 minutes occurred with transmission at 120 bits/sec... hopefully this information will help determine what happened to the Spirit rover 2 days ago...
Easy, Martian atmosphere pressure is only 1% that of Earth's. So whilst the winds on Mars can reach enormous speeds, they actually exert very little force.
Best wishes,
Mike.
Why does every press release have to mention how they are doing it "better" than we Americans are...
The press release doesn't even mention the USA or NASA...
Mars' magnetic field is only a tiny fraction of that of Earth's and is actually dominated by regional poles rather than the strong magnetic poles on Earth. Mars does not appear to have a dynamic Core so its magnetic field is actually the one frozen into the planet when its hot interior solidified.
So a compass wouldn't be much help.
The answer is that the North Martian Pole is the one pointing in much the same way as the Earth's North Pole.
Best wishes,
Mike.
Well, you can have two kinds of poles: geographic and magnetic.
Magnetic is the way your compass points. Planets do not have to have an appreciable magnetic field, so it is possible to have a planet without a magnetic north.
Geographic is based on the direction of a planet's spin. Here's one way to choose geographic north: the right-hand rule.
Stick out your right-hand like you are going to shake hands, but with your thumb pointing upwards. Now curl your fingers in towards your palm. If the curling of your fingers occurs in the same direction as the planet is spinning then north is in the direction of your thumb. If your fingers are curling opposite to the direction of the spin then your thumb is pointing south.
The right-hand rule is used a great deal in the world of physics.
Life is short: void the warranty.
Updated Mars Exploration Rover Mission Status January 23, 2004
The flight team for NASA's Spirit received data from the rover in a communication session that began at 13:26 Universal Time (5:26 a.m. PST) and lasted 20 minutes at a data rate of 120 bits per second.
"The spacecraft sent limted data in a proper response to a ground command, and we're planning for commanding further communication sessions later today," said Mars Exploration Rover Project Manager Pete Theisinger at NASA's Jet Propulsion Laboratory, Pasadena, Calif.
The flight team at JPL had sent a command to Spirit at 13:02 Universal Time (5:02 PST) via the NASA Deep Space Network antenna complex near Madrid, Spain, telling Spirit to begin transmitting.
By increasing the digit at then of of this http://www.jpl.nasa.gov/releases/2004/30.cfm, you can get more news.
This one above is somewhat upbeat. The data rate from this last communication went from 10 minutes at 10 bits per second to 20 minutes at 120 bits per second.
Not quite live streaming, but not yet slashdoted either.
Mars Express has ground-penetrating radar that can read down to 3 miles, so it should see the ice lenses of the cryosphere. We found so much water just from the epithermal neutron counter on Odyssy.
In all seriousness what reason do we have to go to Mars?
That is a difficult question, isn't it? The most common (and vague) answer would be Hillary's, "Because it's there." While that may not seem like a very good reason on the surface, it's really just an attempt to explain a strong pioneering spirit that is pervasive in many cultures.
To actually look at the benefits of space travel however, you need to look at it from an economic standpoint instead of a scientific one. Opening up space to colonization would trigger a new economy. Those who take the step toward space will need various raw materials. Those raw materials are plentiful on asteroids, moons, and planetoids. Thus space based businesses could make a mint by mining and selling raw materials. Those raw materials could then be processed by space smelters and factories. Those factories could then produce a variety of products, including space craft such as cruise ships or colonization ships. Various institutions could then form colonization efforts where the cost is split among the settlers. (Similar to the settlers of the Americas; the Mayflower being a common example.)
But what does this have to do with Mars? Well, space is a pretty vast place. If we assume for a moment that companies become interested in mining asteroids in the belt just past Mars, then we have to ask the question of how they're going to be supported. Sending ships from Earth would be problematic at best, very slow with catastrophic results in case of failure at worst. However, if Mars were used as a staging point for mining support and materials processing, trips back and forth could be substantially shortened.
Of course, all of this requires the development of high thust AND high Isp engines. Of all the options available, only nuclear engines meet the necessary criteria. GCNR (Gas Core Nuclear Rocket) engines can throw the same mass as chemical engines, but have a much higher Isp (3000-5000). These would work well as a launch solution, space plane solution (since they could potentially "breath" atmospheric gases), and as a initial solution for interplanetary travel. However, even GCNR engines have a low Isp when you take into account how much space is out there. Thus the next step would be the development of pure space drives such as Orion or Nuclear Salt Rockets. Both of these would provide an excellent solution for non-landing craft with high thrust, high Isp, and excellent fuel and mass capacity. They'd have so much power, that they could easily carry GCNR space plane crafts as landing shuttles. (The largest Orion design calls for 8 million tons of ship mass.)
More info on propulsion methods on Wikipedia.
Does that help explain it?
Javascript + Nintendo DSi = DSiCade
I'm not an astrophysicist, but based on things I've read, I wouldn't expect 100GeV stuff coming from the sun. But there are other things in the universe (black holes, magnetars) that can make photons and other stuff with that kind of energy, and much higher (I've seen some articles about cosmic rays with energies of ~10^21 eV, although nobody knows for sure where they come from).
As far as distance from the source goes, photons only get scattered if they interact with something . As long as there's not much between 'there' and 'here,' they can get through, even if it does take a while.
[b.belong('us') for b in bases if b.owner() == 'you']