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There's a site that JPL maintains with information, but it's been tough for me to maintain a link to it because they keep reorganizing their file directories. As of the current nano-second, more information is available via the Stardust FAQ.

Also, if anyone would like to get their own name onto one of the next missions (or see if you're already included), here's where you can enter/search for your name aboard the Deep Impact probe, which is heading out to meet with a comet in 2005. Keep in mind though that January 2004 is the deadline for entering new names. For more info, check here for the Deep Impact fact sheet.

Elonka :)

There's a site that JPL maintains with information, but it's been tough for me to maintain a link to it because they keep reorganizing their file directories. As of the current nano-second, more information is available via the Stardust FAQ.

Also, if anyone would like to get their own name onto one of the next missions (or see if you're already included), here's where you can enter/search for your name aboard the Deep Impact probe, which is heading out to meet with a comet in 2005. Keep in mind though that January 2004 is the deadline for entering new names. For more info, check here for the Deep Impact fact sheet.

Elonka :)

There's a site that JPL maintains with information, but it's been tough for me to maintain a link to it because they keep reorganizing their file directories. As of the current nano-second, more information is available via the Stardust FAQ.

Also, if anyone would like to get their own name onto one of the next missions (or see if you're already included), here's where you can enter/search for your name aboard the Deep Impact probe, which is heading out to meet with a comet in 2005. Keep in mind though that January 2004 is the deadline for entering new names. For more info, check here for the Deep Impact fact sheet.

Elonka :)

It's a silicon-based solid with a porous, sponge-like structure in which 99.8 percent of the volume is empty space. By comparison, aerogel is 1,000 times less dense than glass.

The above line, and more, are available here

And yeah, I'd like to play around with some of this stuff as well. The picture of someone holding a 'brick' of it looks like a bad Photoshop job.

Low earth orbit is still in the atmosphere, specifically called the thermosphere it has the least amount but the most energetic particles and is therefore the "hottest" by the definition of temperature. You don't go hard vacuum for 500-600 km.

I recently had to implement code to convert terrestrial time (TT) to martian solar day (MSD). Some interesting tidbits in that research follow.

As you might guess, the extra days in leap years help keep our calendars synchronized with our actual position about the sun (heliocentric longitude). This is called intercalation, and the general rules governing the gregorian calendar cover 400 year periods. Other methods exist which are in a sense more "accurate," but less useful for predicting future dates. Fortunately, the earth is pretty regular in its movement around the sun.

The 0 degree mark for heliocentric longitude occurs at the vernal equinox, an event that can be easily determined from earth, and has been for centuries. In the Iranian calendar, the new year begins on the day of the vernal equinox. Since this event occurs later in the day each year, eventually an extra day must be added. Such calendars are based on observation rather than rule-based model and consequently are implicitly self-calibrating.

Leap seconds, as pointed out, are an entirely different beast, and are meant to shore up the discrepency between our actual rotation and the atomic clocks we use. The current offset is 22 seconds slow officially. Oddly enough, a NASA document from 1997 uses a value of 63 seconds as the offset between TT (terrestial time) and UTC (Greenwich Mean Time). Another from 2000 shows a 32.184 second offset from TT to TIA (atomic). It doesn't exactly correlate or add up, and I'm not precisely sure why that is. Perhaps someone could enlighten me on the matter.

Curiously, our leap years follow the mathematical model while our leap seconds follow the observation method of calibration. Consequently, you can determine the correct date in the future, but not the correct second.

-Hope

I recently had to implement code to convert terrestrial time (TT) to martian solar day (MSD). Some interesting tidbits in that research follow.

As you might guess, the extra days in leap years help keep our calendars synchronized with our actual position about the sun (heliocentric longitude). This is called intercalation, and the general rules governing the gregorian calendar cover 400 year periods. Other methods exist which are in a sense more "accurate," but less useful for predicting future dates. Fortunately, the earth is pretty regular in its movement around the sun.

The 0 degree mark for heliocentric longitude occurs at the vernal equinox, an event that can be easily determined from earth, and has been for centuries. In the Iranian calendar, the new year begins on the day of the vernal equinox. Since this event occurs later in the day each year, eventually an extra day must be added. Such calendars are based on observation rather than rule-based model and consequently are implicitly self-calibrating.

Leap seconds, as pointed out, are an entirely different beast, and are meant to shore up the discrepency between our actual rotation and the atomic clocks we use. The current offset is 22 seconds slow officially. Oddly enough, a NASA document from 1997 uses a value of 63 seconds as the offset between TT (terrestial time) and UTC (Greenwich Mean Time). Another from 2000 shows a 32.184 second offset from TT to TIA (atomic). It doesn't exactly correlate or add up, and I'm not precisely sure why that is. Perhaps someone could enlighten me on the matter.

Curiously, our leap years follow the mathematical model while our leap seconds follow the observation method of calibration. Consequently, you can determine the correct date in the future, but not the correct second.

-Hope

According to this, 22% of all atmospheric methane (a major greenhouse gas) comes from rotting vegetation in wetlands - a natural process. Another 12% comes from rice cultivation, and fully 16% is cow farts.

Are you suggesting that because a huge component of greenhouse gas output is independent of humanity, we shouldn't do anything about it?

There's a page on the Nasa site here that contains links to some downloads. I've not tried any of it yet, though, as I'm at work at the moment...

What you are looking for is here

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.

I think that probes need to send more telemetry as they are in the process of landing. I think the new rovers have done this to some extent because of the Polar Lander problems.

Information here...

Test your landing equipment better. Or at least once.

According to a previous /. story, the airbags were a major risk for this project.

If anything goes wrong the engineers suspect it will be [the air bags]. They failed their first tests and had to be designed and built without a full testing regime.

Now scientists are claiming that this "recently discovered" crater is near the center of the landing elipse. Either someone did not do their homework or they made a BIG mistake.

Scientists also say that they have ruled out hardware problems. Does that include landing equipment? Parachute failure: Beagle2 would have been travelling to fast for the airbags to deploy in time/protect it from impact. Airbag failure: failure to deploy would leave the craft unprotected on impact; failure to detach could cripple the craft. Pathfinder had an issue where an airbag partially obstructed the deployment of the ramp for the Sojouner.

This may have been the cheapest mission of this sort, but it also may be as big a catastrophe as the Polar Lander. If we (people in general) are going to continue spending vast sums of money to send probes and rovers to the planets, comets, and far reaches of the solar system, I for one would like it if we actually got some tangible return on our investment. Galileo, and Voyager, and Pathfinder are/were examples of missions were of incredible worth. That is space exploration as it should be. Take the time. Test your systems individually and together. Ensure that all calculations are correct. Check and re-check everything. As Yoda would say "Do or do not. There is no try." So should it be with any bit of space exploration

Test your landing equipment better. Or at least once.

According to a previous /. story, the airbags were a major risk for this project.

If anything goes wrong the engineers suspect it will be [the air bags]. They failed their first tests and had to be designed and built without a full testing regime.

Now scientists are claiming that this "recently discovered" crater is near the center of the landing elipse. Either someone did not do their homework or they made a BIG mistake.

Scientists also say that they have ruled out hardware problems. Does that include landing equipment? Parachute failure: Beagle2 would have been travelling to fast for the airbags to deploy in time/protect it from impact. Airbag failure: failure to deploy would leave the craft unprotected on impact; failure to detach could cripple the craft. Pathfinder had an issue where an airbag partially obstructed the deployment of the ramp for the Sojouner.

This may have been the cheapest mission of this sort, but it also may be as big a catastrophe as the Polar Lander. If we (people in general) are going to continue spending vast sums of money to send probes and rovers to the planets, comets, and far reaches of the solar system, I for one would like it if we actually got some tangible return on our investment. Galileo, and Voyager, and Pathfinder are/were examples of missions were of incredible worth. That is space exploration as it should be. Take the time. Test your systems individually and together. Ensure that all calculations are correct. Check and re-check everything. As Yoda would say "Do or do not. There is no try." So should it be with any bit of space exploration

Test your landing equipment better. Or at least once.

According to a previous /. story, the airbags were a major risk for this project.

If anything goes wrong the engineers suspect it will be [the air bags]. They failed their first tests and had to be designed and built without a full testing regime.

Now scientists are claiming that this "recently discovered" crater is near the center of the landing elipse. Either someone did not do their homework or they made a BIG mistake.

Scientists also say that they have ruled out hardware problems. Does that include landing equipment? Parachute failure: Beagle2 would have been travelling to fast for the airbags to deploy in time/protect it from impact. Airbag failure: failure to deploy would leave the craft unprotected on impact; failure to detach could cripple the craft. Pathfinder had an issue where an airbag partially obstructed the deployment of the ramp for the Sojouner.

This may have been the cheapest mission of this sort, but it also may be as big a catastrophe as the Polar Lander. If we (people in general) are going to continue spending vast sums of money to send probes and rovers to the planets, comets, and far reaches of the solar system, I for one would like it if we actually got some tangible return on our investment. Galileo, and Voyager, and Pathfinder are/were examples of missions were of incredible worth. That is space exploration as it should be. Take the time. Test your systems individually and together. Ensure that all calculations are correct. Check and re-check everything. As Yoda would say "Do or do not. There is no try." So should it be with any bit of space exploration

Where does the organization end, an another begin? NASA is a good place to examine this murky, yet fundamental, factor of the GPL. Can the GSFC use it internally, without triggering the distribution clauses? All of NASA? The US Federal Government? US Citizens? The American People?

FlightLinux is a customized copy of a standard Linux distribution, adapted to the unique environment of a spacecraft embedded control computer.

The first instance of FlightLinux will be on the 80386EX processor of the currently in-orbit UoSat-12 spacecraft, of Surrey Space Technology, Ltd (UK). As a basis, we are currently using the ELKS distribution, due to its small size. We will migrate to BlueCat Linux from LynuxWorks, and add real-time features as required.

[...]

At the moment, we have not posted any downloadable code, due to issues of export restrictions on satellite control software.

http://flightlinux.gsfc.nasa.gov/ Or by proxy Like these

Solar electric propulsion is hardly new. It's been used for getting communications satellites out to their final geosynchronous orbits for a number of years now, and NASA demonstrated using solar-powered ion engines for interplanetary primary propulsion on Deep Space 1 [nasa.gov] back in '98.

What ESA is claiming is new about this mission is that they'll be combining ion propulsion with gravity assist maneuvers. AFAIK that hasn't really been done yet (although I know some guys at JPL who're working on it), and given how difficult it can be to work out low-thrust trajectories in the first place I would imagine that successfully throwing gravity assists into the mix would be a significant acheivement.

http://www.ghcc.msfc.nasa.gov/MSU/msusci.html

orbiters page at nasa

Basically columbia's structure was overengineered as it was the first. Gotta remember, shuttle was designed in the early 70s when computer simulations were still very crude. Actually the foundations of shuttle design started not long after apollo 11 landed...

While columbia was being built, the designers went and reworked the structure to be optimized as much as possible. They built a test structure and loaded onto a vibration stand since computer simulators were still not up to the challenge. Later on this structure would become Challenger and saved a couple thousand pounds.

Further refinements (thanks in part to huge improvements in computing power) led to Discovery, Atlantis and Endeavor which were all pretty similar in structure, and weighed nearly 7000 lbs less than columbia.

Each shuttle has had increment improvements over earlier versions, and some of the shuttle have been retrofitted with newer avionics systems among other improvements. One of the lesser known ones was the main engine upgrades that made them much more reliable..early engines seem like ticking timebombs when you read about some of the upgrades they've done lately.

panoramic camera

There are a total of nine cameras on the rover. I suspect that the pair of Navcams (which don't have solar filters) would be used for task should the pair of Pancams malfunction.

• Viking Lander A was near 600 kg, 20W antenna, direct to earth communications, 1281 days of operation.
• Beagle 2 was under 30 kg, under 5W antenna, direct to earth capable
• Mars Opportunity is 185kg, UHF antenna to Mars orbiter module, 90 days operation(planned)
• Mars Spirit is about the same as Opportunity

• Viking Lander A was near 600 kg, 20W antenna, direct to earth communications, 1281 days of operation.
• Beagle 2 was under 30 kg, under 5W antenna, direct to earth capable
• Mars Opportunity is 185kg, UHF antenna to Mars orbiter module, 90 days operation(planned)
• Mars Spirit is about the same as Opportunity

• Viking Lander A was near 600 kg, 20W antenna, direct to earth communications, 1281 days of operation.
• Beagle 2 was under 30 kg, under 5W antenna, direct to earth capable
• Mars Opportunity is 185kg, UHF antenna to Mars orbiter module, 90 days operation(planned)
• Mars Spirit is about the same as Opportunity

I have a photo of the White Sands landing, and it is perhaps the coolest shuttle landing photo. Can we all agree that they don't land or launch the shuttle on the coast near Santa Barbara, at least? Check it out for yourself: White Sands Space Harbor

On August 21, 1993 the spacecraft transmitters were turned off during the final approach to Mars to protect the components against shock from the pressurization sequence. After the transmitter was turned off the tanks were supposed to be pressurized and then the transmitters turned back on and communications with Earth resumed, but no further signals were ever received on Earth.

NASA Planetary FAQ

Slightly off topic, but there are some absolutely awesome images of the surface of Venus available here (towards the top of the page).

The Russians first landed probes there in *1970* (all the more amazing to think this was before I was born). Their landers have typically lasted between 20 minutes and 60 minutes before the hostile environment has atmosphere destroyed them.

I would have sent a black lab myself. Beagles never come back.

This must be a job for... Skylab!

(But seriously, I guess you're right. The last time anyone sent a beagle into space, she did indeed never come back.)

The CONTOUR Board concludes that the probable proximate cause for loss of the CONTOUR spacecraft was overheating of the forward-end of the spacecraft due to base heating from the SRM exhaust plume. The CONTOUR SRM nozzle was embedded within the spacecraft to a greater degree than is typical (Fig. 3), and the resultant near-field effect of exhaust plume heating was not adequately accounted for in the design. Overheating may have caused substantial material weakening and structural degradation, which could have led to catastrophic dynamic instability.

This has been said before in some above posts but obviously needs to be said again, BEAGLE WAS NOT IN ANY DANGER FROM THE DUST STORM ON MARS. The dust storm which started on ~ December 14th. has been winding down (look at the Mars Global Surveyor's Thermal Emission Spectrometer images to see current atmospheric dust levels) in the past week and was nowhere near the beagle 2 landing site for most of its duration anyway. Anyway, the USSR's Mars 3 Lander probe is thought to have probably never even transmitted anything from the surface at all. It's suspected that they just wanted to be the first to claim 'first mars surface transmission' and made up the story that the probe actually transmitted a picture which just happened to be nearly completely black(how convienient). I hope Beagle 2 is still alive and on the surface but if it did die it was almost certainly a failure of one of the many(non-redundant to save mass)entry descent and landing system devices, and not a dust storm which is at fault.

The caption for the pic here says that the surveyor moon lander is in a circle but it's not. To see the surveyor get the TIFF high-res image and look at the bottom of that image for a small white "boomerang". The "boomerang" is two of the three legs of the lander, the third is obscured by a black shadow cast by the solar panels.

I guess the current Mars satellites don't have enough resolution for them to photograph the expected landing site

A neat concept. Unfortunately, I think the design team was visualizing the hard pack on a ski slope, or sand dunes in the Mojave, rather than the -100C, ice impregnated, rock hard soil the probes actual hit... basically a sandy glacier. The JPL post-mortem report (http://sunnyday.mit.edu/accidents/mpl_report_1.pd f - 400KB) ripped the project up one side and down the other for poor planning and testing, and virtually non-existant program management. Hell, if the project lead had so much as pitched a prototype off the roof onto the sidewalk at JPL, she would have had a pretty good approximation of what they were in for, IMO.

The upshot was that the project was doomed to failure on the shoestring budget.

This appears to be the joint press release referred to in the space.com article. It diplomatically states that NASA believes that the features detected by the NIMA analysis could be noise in the camera system (don't they have multiple images to use? seems unlikely that there could be a recurring noise pattern over the same pixels).

But Snoopy already went to space!

In terms of expectations/cost factor the Beagle/Mars Express is perhaps the most ambitious one, therefore the high emphasis on what could go wrong in the Beeb article. A kind of be hopeful but keep your fingers crossed thingy.

The answer is possibly related to the Scientists involved.

The Spirit and Opportunity landers may have been made by experienced scientists in scientifically clean labs and using wind tunnels designed for the military.

Beagle2 (not the Mars Express Orbiter) was cobbled together with pop groups and artists. There's a picture of the project PI (Collin Pillinger) pushing Beagle2 on a shopping trolley. This wasn't a "let's play up the low price tag" PR photograph. He really was transporting the lander on a shopping trolley.

There is then the technical complications. NASA have built two remote controlled sem-autonomous rovers, they have been designed to move about on terrain which has never been seen (from the ground) before. The Sojourner rover from the 90s did very little science because it was mostly wheels and batteries. The only thing I remember from the Sojourner mission is a rock named Yogi.

The thing that separates the two missions is really only the PR. NASA tried to get the fancy rover factor that worked well with Sojourner, and even borrowed a few tricks from Beagle2 in their "were using musical tones to represent spacecraft state".

Beagle2, on the other hand, has a PI who can get people to work for free with the promise of fame (and fortune?). using an artist to paint a spotted calibration plate for the spectrometers/cameras which a scientist would have otherwise done. Using a pop group to play the "mission success" tune on landing (which, I have no doubt, will come through in crystal clear surround sound in the Lander Mission Control).

Going to Mars is expensive, Beagle2 was only cheap because a 300 million Euro orbiter was going that way anyway. Venus Express is recycling the Mars Express engineering models (and will be cheap).

It also has less than 1 in 3 chance of success (3 out of the last 5 failed). Nozomi is dead. 100 million USD doesn't buy what it used to.

Not that again! -5:utter, tired lameness. RTFFRB.

I think the source data is indeed MrSid. Apparently the source data is freely available on the internet as well. For example, compare the area northwest of the Hudson Bay (just above the center of the image showing entire Canada ) to this page. (You need to accept a certificate.) Note the two reddish/brownish areas. Coincident? Nah. :) Also the clouds, light reflection and ice coverage is similar to the ESAD images. BTW, Almost the entire world is available at the ESAD site, with 28.5 m resolution.

Another poster has answered this below..

Is this true? (Hopefully using the right term...I mean itemized lists with roman numerials, numbers, letters for each part)

If you mean "itemized" or "enumerated" lists then yes there is a limit it appears you can go 5 deep.

The following will give a "Too deeply nested" error. Due to the "sub sub sub sub sub sub item"

N.B. It it not very pretty due to having to get past the "comment compression filter"...

\documentclass{article} \begin{document} \begin{itemize} \item Item \begin{itemize} \item Sub item \begin{itemize} \item Sub sub item \begin{itemize} \item sub sub sub item \begin{itemize} \item sub sub sub sub item \begin{itemize} \item sub sub sub sub sub item \end{itemize} \end{itemize} \end{itemize} \end{itemize} \end{itemize} \end{itemize} \end{document}

As with many aspects of LaTeX however if you find it doesn't do something it probably means it's not prudent (from a structural perspective) to do it anyway. For example if you really need that level of deep reference you may well be better off with part,chapter,section, subsection, ... . . .,itemize etc... Ironically I tried posting this reply with some deep nesting, slashdot posts are limited to three levels deep! ;-) Of course if you wish to you can always override the builtins with your own "super list" or something.

Also, can ya'll post some good links to a newbie learning LaTex..and some good reference sites that have all the tags layed out with good explanations?

Sure, below are a list places I would reccomend starting, you havn't said if you use Windows, *nix or Mac so i've added both (sorry if you are a Mac man you'll have to Google yourself).

• Editing:
• • *nix If you are a *nix user I would reccomend the following editing combination.
  • XEmacs
  • AucTeX. A sophisticated editing mode for LaTeX
  • preview-latex. Places the rendered equations and images directly in the editor window making "equation tuning" and other tasks a snip.
• Windows
• • WinEdt. A very sophisticated text editor for Windows. Its forte is LaTeX. It is not free, but well worth the money.

• Learning resources:
• • Getting started
  • Good overview
  • A list of symbols
  • The not so short introduction to LaTeX2e
  • Tips and tricks
  • BibTeX help.

• Other random stuff
• • dvipdfm. For converting the output of LaTeX into PDF (highly recommended)
  • Prof. Knuth's home page(The author of TeX).
  • CTANThe Comprehensive TeX Archive Network. Here you will be able to download packages, utilities and tools that do not come by default in your LaTeX distribution.

-ed

Oh.

Except for this bucket of bolts.

Actually, we can remodel an aircraft in flight, using adaptive systems like neural networks. Someday, when your plane loses 20% of it's tail, we'll use the remaining control surfaces to keep it stable and maneuverable.

X-36 Project

The F-15 Active

Actually, we can remodel an aircraft in flight, using adaptive systems like neural networks. Someday, when your plane loses 20% of it's tail, we'll use the remaining control surfaces to keep it stable and maneuverable.

X-36 Project

The F-15 Active

Ahhhh, what the heck, I didn't like my job anyhow:

ftp://nccs.nasa.gov/pub/linux/linux-2.6.0.tar.bz2 ;)

Actually, getting the rocket to fly in the right direction is easy. See NASA's model rocket section here for a simple guide.

Surely it would be easier to create a huge black hole in the centre of the galaxy, and have the stars come to you.

Like this one? Looks like someone is one step ahead of you.

Actually, the Wrights did not invent the wind tunnel (see this link for some history). However, they did put their wind tunnel to good use when designing their craft.

The 'Space Robot' (SR), with an in-built 'RUDAC' communication signal processor, will be used to capture damaged satellites and space debris from crashing to Earth, CSRDC-CSRL and ISRDO Director Dr M Sreedhar Dayal told UNI.

Putting aside the poor translation, it's clear that the article's writer doesn't have much of a scientific background. Unless you're talking about a mass comparable to the Compton Gamma Ray Observatory or perhaps the Hubble, there's not much need to prevent debris from "crashing into the earth". 100,000 feet of atmosphere does a fine job by itself, and puts on a great light show to boot.

The obvious benefit of this space scoop is to clear NEO of the sort of debris that occasionally causes the ISS and the Shuttle to take evasive maneuvers from time to time.

But I know what I'd be interested in, if I were a developing nation with orbital capability. The space around Earth is turning into the next big salvage yard, especially if the costs of this mission are comparable to a high-profile terrestrial salvage operation. What better way to find out what other nations have been doing in the space above your country, than to grab a few samples of their equipment?

It's even better than a earthbound salvage operation, because there's no weathering beyond radiation and collisions with other pieces of debris. A defunct spy satellite would be in as good a condition now as it was the day it entered orbit, especially in terms of reverse-engineering. The chips may have a few bits shorted out, but the circuit boards, wiring harnesses, optics, propulsion systems, and so on could hold a trove of information.

And there's one thing I'm dying to do -- buy space knicknacks. NASA and the Russians could probably fund a significant space program by simply selling off that ton or so of "trash" brought back by each shuttle mission or burnt up in the used Progress craft. If India can bring back space nuts, old thruster bells, and the like, they could make a killing on eBay!

In addition to the general advantages of placing a telescope on the moon (no atmosphere), the far ('dark') side of the moon has a unique advantage: it's always shielded from Earth, which is a huge radio source. For this reason, the far side of the moon would be an ideal spot to build a radio telescope.