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While direct reception of Spirit and Opportunity is probably beyond the capabilities of single-amateur equipment, reception of a continuous wave (unmodulated carrier) beacon transmitted by the Mars Relay Radio System aboard the Mars Global Surveyor on the way to Mars was achieved by amateurs in 1996. At the time, the 1.3 Watt transmitter was approximately 5 million km away from Earth.

The Mars Express probe that launched the ill-fated Beagle 2 lander, and the Mars Orbiter in orbit around Mars, were both detected by this station in November last year, although it stretches the definition of "amateur" quite a bit; also by these guys with much more modest equipment.

For a real challenge, the New Horizons spacecraft, scheduled for launch in 2006 to Pluto and the Kuiper Belt beyond, will employ beacon cruise mode, in which it will send a fixed tone (see page 42), designed for easier reception by amateurs, while cruising in deep space.

Additional information on amateur deep space reception is available here.

An RSS feed from NASA?

Your wish is their command.

I browsed the images and found these raw images of the anomoly:
Filter 2 19nm
Filter 2 20nm

I browsed the images and found these raw images of the anomoly:
Filter 2 19nm
Filter 2 20nm

Did a little research on this specific mission (before I was just talking based on my experience with the much smaller satellites I worked on), and I learned some stuff:

How rovers communicate with earth
- the Deep Space Network (DSN) communicates directly with the rovers, but is busy because it also tracks 28 other missions.
- the rovers can talk to one of two mars-orbiting satellites that will forward the messages.

The forwarders are much better (bigger antennas, more solar cells = better power budget, higher orbit means the earth is visible for a bigger portion of the day), but they're another link in the system and prone to failure. (I'm guessing that they don't provide as many emergency debug options, either)

This page includes a description of the low-bandwidth control channel that communicates directly to the DSN.

I couldn't find mention of how much use the high gain-to-DSN path gets vs. via-relay-satellites path - does anyone have this info?

Did a little research on this specific mission (before I was just talking based on my experience with the much smaller satellites I worked on), and I learned some stuff:

How rovers communicate with earth
- the Deep Space Network (DSN) communicates directly with the rovers, but is busy because it also tracks 28 other missions.
- the rovers can talk to one of two mars-orbiting satellites that will forward the messages.

The forwarders are much better (bigger antennas, more solar cells = better power budget, higher orbit means the earth is visible for a bigger portion of the day), but they're another link in the system and prone to failure. (I'm guessing that they don't provide as many emergency debug options, either)

This page includes a description of the low-bandwidth control channel that communicates directly to the DSN.

I couldn't find mention of how much use the high gain-to-DSN path gets vs. via-relay-satellites path - does anyone have this info?

Did a little research on this specific mission (before I was just talking based on my experience with the much smaller satellites I worked on), and I learned some stuff:

How rovers communicate with earth
- the Deep Space Network (DSN) communicates directly with the rovers, but is busy because it also tracks 28 other missions.
- the rovers can talk to one of two mars-orbiting satellites that will forward the messages.

The forwarders are much better (bigger antennas, more solar cells = better power budget, higher orbit means the earth is visible for a bigger portion of the day), but they're another link in the system and prone to failure. (I'm guessing that they don't provide as many emergency debug options, either)

This page includes a description of the low-bandwidth control channel that communicates directly to the DSN.

I couldn't find mention of how much use the high gain-to-DSN path gets vs. via-relay-satellites path - does anyone have this info?

Wrong. The twin MERs were already planned by the time Mars Polar Lander was lost. Also, future probes are not going to be twin missions; for instance in 2007 the Mars Phoenix Lander is going to be a single mission.

NASA's press releases aren't mentioning a strange object spotted by Opportunity. It's no face on Mars, but it's just as ripe for imaginative interpretation: A snail's eyestalks? A rabbit head? A sea serpent? Under "As Far as Opportunity's Eye Can See", on http://marsrovers.jpl.nasa.gov/gallery/press/oppor tunity/20040202a.html there's a large panorama at: http://marsrovers.jpl.nasa.gov/gallery/press/oppor tunity/20040202a/MSPan_B1_2x-B009R1.jpg and look down under the sedimentary outcrop at right. You can also see that NASA was looking at it on Sol 2, on a series of four images taken on Sol 2, 2/3rds of the way down at: http://marsrovers.jpl.nasa.gov/gallery/all/opportu nity_p002.html but strangely it looks like those pixels are whited-out

NASA's press releases aren't mentioning a strange object spotted by Opportunity. It's no face on Mars, but it's just as ripe for imaginative interpretation: A snail's eyestalks? A rabbit head? A sea serpent? Under "As Far as Opportunity's Eye Can See", on http://marsrovers.jpl.nasa.gov/gallery/press/oppor tunity/20040202a.html there's a large panorama at: http://marsrovers.jpl.nasa.gov/gallery/press/oppor tunity/20040202a/MSPan_B1_2x-B009R1.jpg and look down under the sedimentary outcrop at right. You can also see that NASA was looking at it on Sol 2, on a series of four images taken on Sol 2, 2/3rds of the way down at: http://marsrovers.jpl.nasa.gov/gallery/all/opportu nity_p002.html but strangely it looks like those pixels are whited-out

NASA's press releases aren't mentioning a strange object spotted by Opportunity. It's no face on Mars, but it's just as ripe for imaginative interpretation: A snail's eyestalks? A rabbit head? A sea serpent? Under "As Far as Opportunity's Eye Can See", on http://marsrovers.jpl.nasa.gov/gallery/press/oppor tunity/20040202a.html there's a large panorama at: http://marsrovers.jpl.nasa.gov/gallery/press/oppor tunity/20040202a/MSPan_B1_2x-B009R1.jpg and look down under the sedimentary outcrop at right. You can also see that NASA was looking at it on Sol 2, on a series of four images taken on Sol 2, 2/3rds of the way down at: http://marsrovers.jpl.nasa.gov/gallery/all/opportu nity_p002.html but strangely it looks like those pixels are whited-out

It just seems to me such a simple problem could be overcome, there must be more to it than that.

Google is your friend. Summary is electrostatic forces make small grain dust adhesion formidable problem.

I guess the idea of a redundant rover is to make sure that errors are not a total loss. But it's nice to have both...

Although it may not be effective for all missions, some have been kicking around the idea of landing a bunch of micro-rovers about the size of a shoe-box and let them plunk around. If you had say 8 such rovers they could land in a rough place with lower risk of total loss. With the current crop of probes they understandably pick smooth landing areas. But in the future they may have to target rough areas to get to the next level of knowledge about Mars. The best rocks are often in rough areas. Rather than try to build a super-complex rover to navigate a mess, have a bunch of smaller, simpler ones knowing that a few will get trashed in the process.

There was a cancelled asteroid mission that was to use smaller, four-wheeled rover(s). The wheels on each side are fixed to a rotatable "V" bar. The design seems simple, yet flexible. If one gets stuck, simply flip around on the axle on the V bar. The PDF image (link below) makes it look like the V has independent arms, but other photos I saw had them at a fixed angle. (I couldn't find those images.) Maybe this version did have independent arms. It looks a bit different than other links I saw. It is probably a rough prototype anyhow being that the funding never came through to finish.

http://www.spacedaily.com/news/muses-cn-00b.html

http://www.jpl.nasa.gov/facts/muses.pdf

Most news sites are too damn slow for news on the rovers. Hell, Spirit was fully up and running over two days ago.

Visit the official MER web site from JPL for at least better day-to-day detail.

Another geeky thing to enjoy is Maestro, software that allows anyone to download real data from both landers and observe in exhaustive detail what the JPL guys see (they use a much more complex version of the package). It's Java.

Most news sites are too damn slow for news on the rovers. Hell, Spirit was fully up and running over two days ago.

Visit the official MER web site from JPL for at least better day-to-day detail.

Another geeky thing to enjoy is Maestro, software that allows anyone to download real data from both landers and observe in exhaustive detail what the JPL guys see (they use a much more complex version of the package). It's Java.

Well, the DSN dishes used are 34 and 70 meters, and I think that the size does matter in this case :) I don't know if it's possible with today's electronics to pick up those signals with a backyard dish. Fore more info:

This feature was presented to the mission managers during one of the 'lunchtime lectures' they present in the MOC. I caught a glimpse of this presentation the other night while watching the NASA TV stream. The presenter mentioned /. during his presentation and talked a little bit about the color debate started here a few weeks ago.

This feature was presented to the mission managers during one of the 'lunchtime lectures' they present in the MOC. I caught a glimpse of this presentation the other night while watching the NASA TV stream. The presenter mentioned /. during his presentation and talked a little bit about the color debate started here a few weeks ago.

This feature was presented to the mission managers during one of the 'lunchtime lectures' they present in the MOC. I caught a glimpse of this presentation the other night while watching the NASA TV stream. The presenter mentioned /. during his presentation and talked a little bit about the color debate started here a few weeks ago.

Sorry, but as others have pointed out, this is a non-story. It's a variation of a Dobsonian design. A real story is the story of John Dobson (short bio here), a monk from San Francisco who designed and built the original Dobsonian telescopes and got people interested in astronomy by taking his telescopes to the streets. Being a monk, he lived in poverty and built his telescope as cheaply as possible. Because he had to continue living in poverty, he was unable to sell them and become rich, so now the bigger telescope makers are making money off of his design.

You wanna run a story about amateur telescopes, that's a good one. Or I could point you to the story of the three guys who ground their own 30" mirror and built a telescope from that. There's a lot of cool stuff being done by amateurs. Sorry, but this isn't that cool compared to most of it.

Yep. And also, soils get minerals from rock through simple weathering. No need for just glaciers and such.

The X-43 itself is build by Micro Craft. Only the Pegasus is build by Orbital. http://www.dfrc.nasa.gov/Newsroom/FactSheets/FS-04 0-DFRC.html

Here is a picture (rendering) of this X43.

The X-15 pilots were needed mainly because they didn't have good enough automatic control systems. Now that we have them, there's no reason to risk human lives just to tinker with high-speed rocket planes.

I think this automatic control system is very close to being perfect AI. It's doing a great job of impersonating a pilot that's had a 3 beer lunch.

Not so. The Viking 1 lander was operational for over 6 years, while the Viking 2 lander lasted 3.5 years (see here). So, yes, I think we can manage a year or 18 months.

Read The Case for Mars . Zubrin has covered your objections there.

ranger was the probe that went to the moon in 1965. Humans followed.

It was never the other way around.

Clickey-clickey

NASA's experimental X-43A hypersonic research vehicle, securely mounted to the B-52 mother ship that will launch it, took off from Edwards Air Force Base at 3:21 p.m. Pacific Standard Time Monday, Jan. 26, 2004 for a captive-carry test scheduled for two and a half hours during which the experimental craft remained attached to the B-52.

The photograph Plane shows the B52 bomber - i'm still searching for the hypersonic baby plane

NASA is very good at what it was intended to do. Unfortunately, that's not running a space launch business.

NASA was originally the National Advisory Committee for Aeronautics, with the purpose of "..to supervise and direct the scientific study of the problems of flight, with a view of their practical solution." (official history).

The main difference between the Moon program and the Shuttle program is that getting to the Moon was a development project - the creation of new technology - while the Shuttle program is basically running a business - doing the same thing over and over again. About 1/3 or NASA's budget goes to the shuttle, with little benefit.

Calls for NASA to "just do it" ignore the importance of the research and development. As an example, getting to Mars may cost only a fraction of what it would cost today, in about ten years time, as many of the propulsion technolgies reach maturity and can be developed into practical systems. But if those programs are abandoned to go to Mars now, then in ten years the cost will be little different. In other words, if NASA is allowed to do its job, the world may have the opportunity to get to Mars affordably, but if it's done now without adequate technology, only a few humans will ever set foot on the planet for a very long time (much like what happened with the Moon).

A comparison might be communicating across the U.S in the 19th century. One way to communicate quickly would be the Pony Express. Within a few years, the telegraph had been developed - technology produced a much more affordable solution. NASA is in a position of being the only ones developing certain types of technology, which means that directing resources away from that research will postpone its development, which would cripple space flight for the world.

You could argue that the rest of the world should spend more effort on this research themselves. It should. But since it doesn't, we're stuck with deciding how NASA can contribute most to humanity.

Online at Space.Com

The Online Columbia Loss Faq, compiled through March 2003 much of which might be outdated, but good for lots of small details, and a sense of the history as it happened.

The Columbia Accident Investigation Board Website, due to become inactive on February 1st, 2004 (!)

People might want to download the final report while they can, dated October 2003, although It is also available on the Nasa Website here

None of the components you listed in your message do us much good for a manned Mars exploration program. Take the Shuttle engines you list as one component. Only they aren't. They're needed in the (remaining) Shuttles. We'd have to build more of them to make a Mars mission possible before the end of the next decade - many, many more of them.

Let's see, 1 launch window every 2 years, 2 vehicles per launch window, 4 engines per vehicle = 4 engines per year. Manufacture of High Pressure Fuel Turbopumps: "Production rate > 1 unit / month since first flight in July 2001 (STS-104)[1]. At the rate of 1 unit per month, you could have enough engines to fly a Shuttle every month and replace engines every 5 flights, send 4 vehicles to Mars every launch window instead of 2, and have about 3 brand-spanking new engines left over.

It would take several launches just to get the gadgets to Mars to make liquid water and oxygen and hydrogen and everything else for the astronauts to use once they finally arrived.

It would take one launch, carrying about 50 tons on a trans-Mars orbit.[2] The Shuttle orbiter weighs about 100 tons fully loaded; its engines are around 10 tons, leaving 90 tons for vehicle, payload and trans-Mars injection fuel. The required delta-V to get from LEO to TMI is roughly 4.3 km/sec. [3] Vacuum-specific impulse of an SSME is 452 seconds [4], or exhaust velocity of 4430 m/sec; the required TMI mass-ratio is 2.64 by the rocket equation. If you retained one SSME (modified to be restartable in flight) for the trans-Mars injection, you would need to start with ~53 tons * 2.64, or roughly 140 tons. This appears to be well within the capacity of a vehicle using 4 SSMEs and 3 SRBs to put into LEO.

Then there are the cargo / habitat landers, which also cannot fail.

Yes they can. You send them first, perhaps several of them, one launch window before you send people. If they don't land and work correctly, you hold the manned mission off for another launch window. If you send 3 and only 1 of them lands and works, you have one usable landing site; if 2 or 3 of them land and work, you have your choice of options. You can use the unused landers later, or for supply depots for long surveys.

In-situ propellant production may have been demonstrated in the lab here on earth, but we don't know yet if it would even work on Mars. Right now we're having trouble getting simple robot rovers to function correctly, at $400 million a pop.

You have some serious misconceptions about price tags here. The cost is almost entirely for research, development and engineering; manufacturing is a drop in the bucket. You could probably crank out rovers for a few million apiece now that we have the design.

A small chemical plant is much, much simpler than a rover. The biggest issue might be filtering dust to keep it out of the machinery, and you would have a lot of trouble claiming that we don't have any applicable experience with filters.

What you're proposing is that we drop a small chemical factory on Mars, along with an automated tractor and bulldozer to haul it icy rock for processing.

No, that's your proposal. I'm proposing Zubrin's scheme of carrying LH2 to the site and processing it into methane and LOX via the reactions

CO2 + 4 H2 -> CH4 + 2 H2O + heat

H2O + energy -> 2H2 + O2

Note that the methane-production reaction is e

Mars Rover Sample Return (MRSR) has been in development since the 1980's. Initially the Pathfinder program, which eventually spawned the Pathfinder mission, was designed to demonstrate the technologies for the MRSR. MRSR is classic vaporware. It has gone through several complete revisions including one that had a 1100 pound rover and a cost of $10 - $13 billion. MRSR if it ever launches will probably take place after the Mars Science Laboratory mission (if it ever launches). While it sounds like a cool idea to bring back rocks to give intense scientific analysis, I think it is more practical on science earned per dollar cost to invest other technologies such as a rover or lander that can drill far beneath the surface for samples, multiple advance seismic detectors, or rovers with ground penetrating radar. Many of these mission could be done for the same cost and a fraction of the failure probability of MRSR.

I was surprised to see you say refer to a NASA mission as non-JPL. What do you mean by this? Isn't JPL is a part of NASA? Also, what about this

No it's butterscotch.

The good news is the disc is right there on the rover.

The bad news is the robot arm is going to have to wrestle the Lego guy for it. And the Lego guy gets to use the arm he HASN'T been holding up in air for eight months solid...

Do they mean Lidar perhaps?

Vik :v)

considering Bush's plan calls for a $1B increase in NASA funding over _5_ years, and plans for the first new moon landing is set for 2015.... it's obvious that Bush's plan is an investment into setting a new vision for NASA, not for implementing it. This is a big difference that I don't think many people fully appreciate.

This does raise some questions:

(1) What's the real mission gonna cost?

(2) How in the heck will we pay for it?
and most importantly:

(3) If we don't have really solid answers to (1) and (2), is a Mars study the best thing NASA can do with $5 billion?

I mean, think about it: That $5 billion would save the Hubble several times over, and fund more science missions like Mars Spirit Rover, Stardust GALEX, New Horizons, etc, etc. Doesn't it make more sense for the space scientists to decide how to spend the $5 billion than letting Washington politicians decide? The National Science Foundation, the National Institutes for Health, and DARPA all have a pretty good track record for peer-reviewed funding decisions; why not space science too?

considering Bush's plan calls for a $1B increase in NASA funding over _5_ years, and plans for the first new moon landing is set for 2015.... it's obvious that Bush's plan is an investment into setting a new vision for NASA, not for implementing it. This is a big difference that I don't think many people fully appreciate.

This does raise some questions:

(1) What's the real mission gonna cost?

(2) How in the heck will we pay for it?
and most importantly:

(3) If we don't have really solid answers to (1) and (2), is a Mars study the best thing NASA can do with $5 billion?

I mean, think about it: That $5 billion would save the Hubble several times over, and fund more science missions like Mars Spirit Rover, Stardust GALEX, New Horizons, etc, etc. Doesn't it make more sense for the space scientists to decide how to spend the $5 billion than letting Washington politicians decide? The National Science Foundation, the National Institutes for Health, and DARPA all have a pretty good track record for peer-reviewed funding decisions; why not space science too?

that's planned for 2009 mars science laboratory
(#2)

...Maybe they should be running qnx or a form of realtime linux/bsd? Something to think about for future missions perhaps.

Quite a lot has been thought about it, for a starter see Flight Linux, but this is an extremely non-trivial question. When building flight hardware, the designs tend to be extremely conservative. VxWorks has been used successfully on previous missions, so it is a known quantity. As far as I know, the same can't be said for Linux, and certainly standard Linux is not a RT OS. Getting one of the RT versions of Linux up to a standard that could be used in flight will take a susbstantial effort by someone, and this has to be done to, and documented in line with the appropriate methods, not something that any space agency is likely to allow amateurs to do in the near future.

On the other hand, NASA has developed a new space telescope with a better mirror that is scheduled to be launched in 2011.

It is very important for NASA to do valuable science, but why not do it cost effectively? The cost of a shuttle mission, estimated at about $400m - $500m, is almost half of the whole budget for the next generation space telescope ($825m).

The Hubble will eventually fall out of orbit and crash to Earth, probably in 2011 or 2012. To make that event safe, Grunsfeld said, NASA will design and build a small robot craft that will be launched and guided to the Hubble.

The robot craft would "grab the Hubble and bring it into the atmosphere in a controlled manner," he said, guiding the school-bus-sized craft to harmlessly splash into a remote part of an ocean.

What I think we should be developing, in addition to a shuttle replacement, is robotic repair vehicles that we could use in case of a backup, or in cases of hardware that we really don't want people risking their lives for.

We're working on technologies for that right now, through things like NASA's Demonstration of Autonomous Rendezvous Technology mission and DARPA's Orbital Express program. Right now we don't have good sensors for bringing two crafts together under robotic or tele-robotic control. With luck, we'll have them working and working well in the very near future.

And yeah, I am a rocket scientist.

Now think what you could build with that money in todays technology. I would suggest reusing some of the detectors designed for the next service mission. Use a modern light-weight mirror. No options for repear in space, just launch and forget. If it blows up, build another one. Mightbe be really modest in your goals, don't go for a design that is 10 times better than hubble, but try to equal it with a mirror of 1.5 - 2 meter. I don't know the exact number, but i believe SIRTF was built for something between 0.5 and 1B$. I would guess this could be done for less than 1B$ within 3 years to close the gap till NGST is built.

Hubble gave us a new perspective on what it means to feel small and insignificant in the universe. Take a look at all the images it has produced- I've downloaded many and had them dumped to AgX paper so I can hang them up on the wall.

Hell, just click over to the hubble site here http://hubble.nasa.gov/image-gallery/ and you'll see star formation.

Just don't take away the tool that has cleaned a small bit of grease off the window to the universe and let us see what's out there. We need more photos to help 'instruct' some people down here that already are too big for their own good.

Disengaging the boosters early (while they're still running) isn't possible. There are a number of "abort modes" once the boosters have burned out though; see this link.

I guess you'd have to ask NASA

how fast is -your- 512p intel-architecture supercomputer?

You can't seal it because the case can't take the pressure.

Also, moving parts are a lot more temperature-sensitive than silicon. They have lubricants which sieze up and thermal expansion which messes up all the tolerances.

CMOS generally works better at lower temperatures, and the usual low-temperature limit is simply what the manufacturer bothers to test because that's the customers want to pay for. You may have seen pictures on the web of overclockers dunking Intel's microprocessors in liquid nitrogen (approx -196C = -321F) which is way outside of their specified temperature range) and they run just fine.

You can find web pages on the design of seriously cryogenic (liquid helium and below) preamplifiers and the like. It does things to standard transistors, but they can still be used.

The main thing you have to watch out for with wide temperature extremes is thermal expansion stresses cracking the IC packages (metal lead-frame expands more than plastic case) or breaking the solder joints to the board.

But basically, sometimes equipment can be run well outside its normal specifications safely if you understand how it's made and what the effects of the variation are in detail. Rated temperatures mean that the manufacturer promises that the equipment will work at those temperatures and hasn't spent much effort ensuring it'll work outside those temperatures, but it doesn't mean the gadget is guaranteed to not work outside those temperatures.

With careful part selection, you can do some pretty impressive stuff. There are folks who build instruments for the bottom of oil-well drills, a high vibration environment swimming in 200C cooling/lubricating "mud", out of carefully selected standard commercial components.

Now the problem with two processors - if they disagree, how do you decide who's right? And how much chance for error does your deciding circuitry add to the system? While processors usually fail stopped fairly quickly, doubling the number of processors doubles the chances that something will fail in a more creative manner.

These guys are not idiots. They thought through the implications very carefully. The RAD6000 processor is very thoroughly tested in space and has an excellent reliability record.

Having said all that, I do wish I could find more on the web describing the design decisions made. There's generally some very good engineering in these things, and the stuff I've read like this History of Apollo Launch Facilities and Operations is fascinating.

And whoever complained that they were still developing the software after launch - well, they had 6 months, and I'd be surprised if they couldn't find one bug or worthwhile enhancement in that time. They can do remote upgrades, and might as well take advantage of it.

Both of these previous comments are basically correct. There are five GPCs (General Purpose Computers) in the original configuration of the STS. I've heard them compared to a 286 before. During a mission, three run the primary flight software, one is a hot spare and one has the BFS (Backup Flight System) loaded. The BFS is a no-frills ascent/descent/abort program.

During normal operations, the three primary computers perform their calculations and compare the results. If one of the computers disagrees, it is taken offline and the hot spare is brought online. The crew receives a master caution alarm and the commander is tasked to handle the problem since the GPC panel is over his head. If a second failure occurs then the system dumps to the BFS and you start looking at abort situations. They computed the probability of a double failure at four in a billion. However, YMMV.

If you want to know the whole story on the computers go to Computers in Spaceflight Chapter 4.

I read an article about the the flight software. The reliability they achieve is phenomenal. Orders of magnitude over what any of us will ever see unfortunately.

.

Now you people at the JPL, don't go getting any ideas from this...