Re:Spirit not that impressive...?
on
News from Mars
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· Score: 1
"it weighed just under 2,000 pounds and was designed to operate for 90 days while guided in real-time by a five person team at the Deep Space Center near Moscow"
That's a whole lot different than the semi-autonomous driving of the MER's. You may think it's dull, others see the value in going easy, step by step, evaluating each step before a bigger step is taken. Well, maybe it is dull, but IMHO it's the right thing to do with a $800 million asset...
I like the Mozilla user interface better, and the preferences section too. In Firebird many things are being dumbed down, and to get the same functionality as in Mozilla you need to download and install several extensions, that may or may not work. And then do the same thing with each update:-/ Mozilla gives me one single archive to download, extract, copy plugins over, (make backup of profile directory just in case) and run.
Okay, I challenge you to wear a BSD t-shirt and walk around several south-US states (texas would be a good one).
Trust me, those religious nuts will have you arrested. And bring the asbestos underwear because they'll probably try burning you as a devil worshiper...
While your comment is funny, IMHO the difference is that in those days NASA didn't have as many obligations to big, long term projects as it does now. I'm pretty sure a moonlanding can be done in 5 years, but not without a huge funding increase. And that will never happen, ofcourse. In a later briefing NASA director O'Keefe said that the funding increase shown on Bush's slides is pretty much inflation correction. Don't know enough about the US economy, and too lazy to google, to tell if that is correct.
Maybe that was a bit harsh, but have you ever seen a sophisticated piece of consume electronics, such as a Palm Pilot or laptop, taken along with astronauts on their missions?
Yes, laptops, they run Windows, and you can read about the scheduled reboots here in the status reports.
Other space news sources (like Spaceflight Now) mention the fact that the leakage was already known late last year, dec 29 IIRC. Maybe your parent knew that. Then again, that still makes it less than half a month.
the precision would be so bad that they could spend their entire 90 day mission searching the area without ever finding the probe
Spirit landed 6 or 7 miles off the target point (IIRC), and that is considered hitting the bullseye on planetary missions. The rovers range is supposed to be about one mile max. And the Beagle 2 position is unknown. So, the chance of finding it would be very, very small indeed.
Yes. Let me eat my own words, I've stated here before that Beagle 2 was privately funded. It was not. It was originally meant to be privately funded, but that's not how it turned out. Still, it was a very cheap mission, considering the possible return value. Here is some more info on the funding, just click... "Funding":)
Colin Pillinger was asked that very question: "WHY didn't you include such a device?". The answer was clear: to do that within the very limited weight restrictions (that already had been halved) it would have meant giving up more science. 5 kilograms worth of science. That's about 15% of the lander weight (without heat shield and such).
It all boils down to: you build the best spacecraft that you can within budget and weight restraints, and hope for the best. Even if you build in a lot of redundancy, there is still chance of failure. At some point you need to decide what to do: take a chance, or lose science. I guess in the end different people will come to different conclusions on how much of a chance you're willing to take.
Just in case you (or someone else) don't know: the solar panels degrade over time because of dust build up. So at some point it will just run out of juice...
"The data rate direct-to-Earth varies from about 12,000 bits per second to 3,500 bits per second (roughly a third as fast as a standard home modem). The data rate to the orbiters is a constant 128,000 bits per second"
I'm having trouble getting to the Mars Odyssey page (NASA.. slashdotted!!.. ) but I'm sure the orbiter->earth datarate is a lot more than 10 bits/sec.
"IRC? What's that?"
"Oh, it's just like having a MSN chat with more than 1 person at once." "Oh, I often chat with my buddy and my mom at the same time."
"No... all the people in one window." "Huh?"
"Spirit is being sent to Gusev Crater, a depression the size of Connecticut that scientists believe once held a lake. It is set to land Saturday."
January 3, 11:35pm EST 8:35pm PST in the US, january 4, 4:35am GMT 5:35am CET in Europe for those planning to slashdot the website waiting for news of the landing:)
Does anyone know the different purposes they have?
Quick list, by no means meant to be complete, just to give an impression of the differences between the missions:
Beagle 2: Lander, search for signs of past or present life on the planet surface Mars Express: Orbiter, study atmosphere and surface with radar and spectrometers Mars Rovers: 2 Landers, search for signs of past or present water (NASA's Follow The Water strategy) Nozomi: Orbiter, study atmoshpere and interaction with solar wind. Mission failed.
Come on... go sit in the corner like I told you before. Heat braking was followed by parachute deployement. The fact that pathfinder used a couple of retro rockets to slow down final landing speed had nothing to do with heat breaking. Really, I mean it, go away. Sit in a corner. Suck on thumg, and wait until you're old enough to enter grown-up's discussions.
It is sitting on Mars alright. The trajectory that it was on when released from Mars Express made it pretty hard to miss the planet. What state it is sitting in is what needs to be determined. Now go sit in the corner and be quiet until you are old enough to vote.
Only one probe to Mars (Nozomi) from the current missions failed so far. The Mars Express mission is still 100% succesfull, only the Beagle 2 lander is performing subnominal;) The first MER, Spirit, will attempt landing on Jan. 3, the second a couple of days later.
That depends on the current state of Beagle 2. If it's in pieces scattered around, even Mars Express can't do anything to chance that, unfortunately. But.. if it landed succesfully, then the failure to communicate could be caused by a number of things. For one, the software might have some error in it, it may have its time wrong, one or two of the solar panels may be shielding the antenna.
Some of the possible failure scenarios might be fixed by sending certain commands to the lander. Ie: tell it to move the panels, or to reset the internal clock. That last one has already been tried via Mars Odyssey, but it did not result in success (obviously). AFAIK, these commands have to be sent through an orbiter.
Why put so much hope on Mars Express then? As someone else already posted: the communication link through MEX is the only one thoroughly tested, end to end. Talking to a spacecraft is not easy, many things can go wrong. One of the things currently being looked at is if the Odyssey's tranceiver may be damaged in the recent solar storms. If that is the case then MEX might still have a chance of sending commands to the lander.
In 1997, Mars Pathfinder successfully landed on Mars and deployed a rover. That demonstrated that the design worked, and that all the various hardware and software pieces could come together for a successful mission.
Did Mars Express / Beagle 2 reuse any of that, or did they start from scratch?
They used similar landing technology. For the rest there was not much that could be copied or emulated, since the Pathfinder was a couple of magnitudes bigger than the Beagle 2.
Yup... All these folks ready to give up on a "shoddy euro spacecraft" are probably forgetting all the months of searching for NASA's Polar Lander, and Jodrell Bank and Westerbork observatories pitching in to do their part in that search.
What kind of shoddy poster believes anything in the slashdot write up of an article? There is no need for a command to recharge batteries. When the lander was being designed, there was no agreement yet with NASA to use the Mars Odyssey probe for communications, and the use of Jodrell Bank Observatory was only agreed on after launch of the Mars Express (IIRC).
So, during design, the only available method of communication would be Mars Express. It was already known that for several days after landing, MEX would not be in position to talk to the lander (due to the need to change its orbit from equatorial to polar).
Thus they had to plan for the lander to stay alive and healthy on its own for at least 10 days. That is why it was programmed to automatically recharge its batteries as soon as the solar panels were unfolded and the sun would appear.
Slashdot Mirror
That's a whole lot different than the semi-autonomous driving of the MER's. You may think it's dull, others see the value in going easy, step by step, evaluating each step before a bigger step is taken. Well, maybe it is dull, but IMHO it's the right thing to do with a $800 million asset...
I like the Mozilla user interface better, and the preferences section too. In Firebird many things are being dumbed down, and to get the same functionality as in Mozilla you need to download and install several extensions, that may or may not work. And then do the same thing with each update :-/ Mozilla gives me one single archive to download, extract, copy plugins over, (make backup of profile directory just in case) and run.
Trust me, those religious nuts will have you arrested. And bring the asbestos underwear because they'll probably try burning you as a devil worshiper...
That has been done.. Read this nice short story :)
While your comment is funny, IMHO the difference is that in those days NASA didn't have as many obligations to big, long term projects as it does now. I'm pretty sure a moonlanding can be done in 5 years, but not without a huge funding increase. And that will never happen, ofcourse. In a later briefing NASA director O'Keefe said that the funding increase shown on Bush's slides is pretty much inflation correction. Don't know enough about the US economy, and too lazy to google, to tell if that is correct.
Yes, laptops, they run Windows, and you can read about the scheduled reboots here in the status reports.
Other space news sources (like Spaceflight Now) mention the fact that the leakage was already known late last year, dec 29 IIRC. Maybe your parent knew that. Then again, that still makes it less than half a month.
Well, no... but it's certainly not the first time that windows leak resources... ...space intentionally left blank for groans...
I don't know either, just repeating what the head of the project said in one of his briefings.
Spirit landed 6 or 7 miles off the target point (IIRC), and that is considered hitting the bullseye on planetary missions. The rovers range is supposed to be about one mile max. And the Beagle 2 position is unknown. So, the chance of finding it would be very, very small indeed.
Yes. Let me eat my own words, I've stated here before that Beagle 2 was privately funded. It was not. It was originally meant to be privately funded, but that's not how it turned out. Still, it was a very cheap mission, considering the possible return value. Here is some more info on the funding, just click ... "Funding" :)
It all boils down to: you build the best spacecraft that you can within budget and weight restraints, and hope for the best. Even if you build in a lot of redundancy, there is still chance of failure. At some point you need to decide what to do: take a chance, or lose science. I guess in the end different people will come to different conclusions on how much of a chance you're willing to take.
Just in case you (or someone else) don't know: the solar panels degrade over time because of dust build up. So at some point it will just run out of juice...
"The data rate direct-to-Earth varies from about 12,000 bits per second to 3,500 bits per second (roughly a third as fast as a standard home modem). The data rate to the orbiters is a constant 128,000 bits per second"
I'm having trouble getting to the Mars Odyssey page (NASA .. slashdotted!!.. ) but I'm sure the orbiter->earth datarate is a lot more than 10 bits/sec.
Google calculator to the rescue!
"IRC? What's that?"
"Oh, it's just like having a MSN chat with more than 1 person at once."
"Oh, I often chat with my buddy and my mom at the same time."
"No... all the people in one window."
"Huh?"
January 3, 11:35pm EST 8:35pm PST in the US, january 4, 4:35am GMT 5:35am CET in Europe for those planning to slashdot the website waiting for news of the landing :)
Quick list, by no means meant to be complete, just to give an impression of the differences between the missions:
Beagle 2: Lander, search for signs of past or present life on the planet surface
Mars Express: Orbiter, study atmosphere and surface with radar and spectrometers
Mars Rovers: 2 Landers, search for signs of past or present water (NASA's Follow The Water strategy)
Nozomi: Orbiter, study atmoshpere and interaction with solar wind. Mission failed.
Come on.. be helpful. Do a traceroute to see at which host it fails ;)
Come on... go sit in the corner like I told you before. Heat braking was followed by parachute deployement. The fact that pathfinder used a couple of retro rockets to slow down final landing speed had nothing to do with heat breaking. Really, I mean it, go away. Sit in a corner. Suck on thumg, and wait until you're old enough to enter grown-up's discussions.
It is sitting on Mars alright. The trajectory that it was on when released from Mars Express made it pretty hard to miss the planet. What state it is sitting in is what needs to be determined. Now go sit in the corner and be quiet until you are old enough to vote.
Only one probe to Mars (Nozomi) from the current missions failed so far. The Mars Express mission is still 100% succesfull, only the Beagle 2 lander is performing subnominal ;) The first MER, Spirit, will attempt landing on Jan. 3, the second a couple of days later.
Some of the possible failure scenarios might be fixed by sending certain commands to the lander. Ie: tell it to move the panels, or to reset the internal clock. That last one has already been tried via Mars Odyssey, but it did not result in success (obviously). AFAIK, these commands have to be sent through an orbiter.
Why put so much hope on Mars Express then? As someone else already posted: the communication link through MEX is the only one thoroughly tested, end to end. Talking to a spacecraft is not easy, many things can go wrong. One of the things currently being looked at is if the Odyssey's tranceiver may be damaged in the recent solar storms. If that is the case then MEX might still have a chance of sending commands to the lander.
Did Mars Express / Beagle 2 reuse any of that, or did they start from scratch?
They used similar landing technology. For the rest there was not much that could be copied or emulated, since the Pathfinder was a couple of magnitudes bigger than the Beagle 2.
Yup... All these folks ready to give up on a "shoddy euro spacecraft" are probably forgetting all the months of searching for NASA's Polar Lander, and Jodrell Bank and Westerbork observatories pitching in to do their part in that search.
So, during design, the only available method of communication would be Mars Express. It was already known that for several days after landing, MEX would not be in position to talk to the lander (due to the need to change its orbit from equatorial to polar).
Thus they had to plan for the lander to stay alive and healthy on its own for at least 10 days. That is why it was programmed to automatically recharge its batteries as soon as the solar panels were unfolded and the sun would appear.