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Wouldn't it be fun if clouds were turtles? Wouldn't it be fun if the laundry on the bedroom chair was a friendly monster? Wouldn't it be fun if rock mesas on Mars were faces or interplanetary monuments? Clouds, though, are small water droplets, floating on air. Laundry is cotton, wool, or plastic, woven into garments. Famous Martian rock mesas known by names like the Face on Mars appear quite natural when seen more clearly, as the above recently released photo shows. Is reality boring?

No. Some x-rays are reflected. Search the web for the Compton Effect.

I presume the x-rays in question come from the Sun. The spacecraft probably acts like an orbiting X-ray fluorescence spectrometer.

the 'genes' part is new (and very cool) but the 'snakebot' as a concept has been around for a while. NASA announced something like it in OCT-00 nasa and this guys tried to put it in layman terms: here

http://www.giss.nasa.gov/research/observe/surftemp /, though unless you have at least undergraduate meteorology / geosciences / SCAS or remote sensing experience, (or have grabbed a text somewhere and run through it, done some of the math for yourself,) I'm afraid it's just not profitable to argue much with you about about it.

I continue to be shocked at the degree to which A) the general citizenry feels that all of a sudden they are more expert than the community of global climatologists, who are, yes, appropriately skeptical folks and aware of the limitations (especially computational) of what we can do, but essentially all convinced that we're screwing ourselves through some pretty dire and well-understood atmospheric mechanics. No one seems to give the same amount of disrespect to physicians with an approximately equivalent level of traning just because the tobacco industry can sow rumors and periodically produce an iconoclast pseudo-scientist.

If you're going to bring out the orbital precession / Dyson fertilization effect / cloud albedo / solar cycle arguments, or that Godawful Smithsonian meta-study, we can do that, but you had better have something better than handwaving and adolescent sarcasm - I want numbers and a hyopthesis, and here's a warning - none of those things quite hold up...

Here is a nice satellite pic comparison of the Northeast before and during the outage from Natural Hazards

Yes, they did. The first one was put there by Armstrong and Aldrin, so it was available from day one...

Some interesting results over the years:
"Ranging has also determined that the length of an Earth day has distinct small-scale variations of about one thousandth of a second over the course of a year, caused by the atmosphere, tides, and Earth's core. In addition, precise positions of the laser ranging observatories on Earth are slowly drifting as the crustal plates on Earth drift. The observatory on Maui is seen to be drifting away from the observatory in Texas."

Relavent link

1) How about a large array of solar arrays in orbit above the planet. They could soak up pure sunlight, and fire it down to the earth in the form of a laser at ground-bound solar arrays waiting for bursts of light. Of course there would be drawbacks: Birds flying through the beams would be vaporised, as well as any aircraft which accidentally strayed off course, and there's always the chance that something might hit a satellite, shifting its aim to target a busload of nuns.

2) Combine power generation with them space elevators we keep hearing about. Aren't those supposed to generate some huge amount of static electricity? You know, giant metallic strand kilometers in length, raking the sky all the way up to zero atmosphere... Why not harness it? I have no idea how we'd get the power back down to the ground, but hey. I'm just a kook.

3) Um... geothermal taps at active volcanoes? Not necessarily a *smart* investment, but it's hot, and we know how to get electricity from hot dirt.

4) Electroactive polymers. If we can find a way to manufacture these little pads inexpensively, then why not have them running under sidewalks, highways, stairs, bowling alleys, basketball courts, train tracks, treadmills, carpets (especially at your local all-you-can-eat Chinese buffet)... They *have* to be pretty resilient if the military is planning to stick them in troops' boots. Every time a car rolls by or a pudgy fellow trundles over to get a fifth bowl of kung-pao chicken, you'd be getting something out of it.

5) Put great big magnets on top of cars, and run large coils of wire around all highways. Okay, that was stupid.

6) Attach generators to doors. All doors. Turnstyles.

7) If only there were a way to safely transmit power. Wouldn't it be great to have all of the icky nuclear power plants to the moon and just have them send the energy home? Maybe something with quantum-entangled pairs of stuff? Like have one member on the moon being jiggled like a maraca by a nuclear furnace and the other half on Earth having its quantum-jiggles somehow harnessed for its energy?

Probably not, huh?

There are weirder possibilities, too. In their first four-cone experiment, the Neitzes think they would engineer a photopigment sensitive in the visible light spectrum (probably in the gap between our current blue and green cones). But they could also make a cone receptive in the infrared zone. If the cones were to become too sensitive to infrared light, though, we would start "seeing" our own body heat, and that would blur our vision. But if you could engineer cones that were somewhat sensitive to the infrared spectrum, we might have extraordinary night vision -- without goggles, street lights, or surgery.

Somehow, even during the blackout, it doesn't look as bad as North Korea on a normal night.

That doesn't make much sense to me (about Columbia). As noted upthread, the Hubble is 130 mi higher than ISS, which you may recall the Columbia was too heavy to reach.

I don't really see how they could have brought it down in the Columbia--what was special about Columbia that made it their pick for retrieving the Hubble?

Although this will lead up to manned missions, you're jumping the gun a bit. The plan for 2008 is unmanned. Not that we should think less of it. It doesn't have to be a manned mission to return good science, and an unmanned mission is a better way to test the tech than a manned mission. USSR did an unmanned sample return. Manned or not, it's still a country going to the moon, and may be the first of the millennium unless it spurs other countries to act faster. I for one would like another space race.
When India moves on to manned moon missions, it will add a new facet to space. The moon has a religious significance for a part of India's population, including India's President who was a pioneer of the space programme. Some Indians will have a chance to go to one of the holiest places off Earth.
BTW, a couple of posts have refered to Sqn Ldr Sharma. Another Indian went into space too, although by US law she may have had to renounce Indian citizenship to become a US citizen.

I heard somewhere that the newer ground-based optical telescope with adaptive optics can equal or exceed the Hubble's resolution.

This is true, with limitations:
1. Adaptive optics requires a bright star in the field of view, limiting the amount of sky coverage possible. While every generation of adaptive optics improves in how faint this "guide star" is, we are still in the early stages of engineering.
2. As an alternative to 1, an artificial, laser guide star can be used. Again, these are in only the earliest stages of engineering. Further, there are concerns such as the interaction of such lasers with aircraft/pilots.
3. Adaptive optics works better in the Near-Infrared than at visible wavelengths. To obtain fully diffraction limited images, most AO telescopes cannot operate in V.
4. Sensitivity. By escaping the earth's atmosphere, one can gain much more sensitivity on the whole. One can "see deeper". This is the fundamental limit of ground-based astronomy, and is why it is unlikely that any amount of engineering will compensate for not being in space.
5. Precision. The earth's atmosphere also limits the precision of many measurements, such as photometry. As an example, look at Charbonneau's results with Hubble studying a transitting extrasolar planet. This precision could not be done from the ground, AO or not. Popular story here. Original paper here.

I think it's a good thing that countries like India and China have their sights set at the moon.
The sooner we start mining the He3 up there, the better.
For the whole planet's sake, we've gotta start colonising the moon.

I don't know, but is landing the space shuttle with more weight a good idea?

Sometimes the shuttle bay is filled with things when it comes down, but the hubble is quite a peice of metal. How does it compare to other things it has landed with.

Disclaimer: I work for NASA, however I write software.

They should try to park the next one as far away from Hubble as possible. There might be some interesting things we could see with such a huge effective aperture.

Hmm... Not sure what exactly you mean by this. If you're talking simple parallax-based astrometry, the hubble c an already do this effectively by taking measurements of the same stars at different points in the Earth's revolution around Sol. This gives it an effective baseline of 2 A.U. No tandem satallite in earth orbit can possibly match that.

Perhaps you're talking about aperture synthesis interferometry? This is what is used by things like the Very Large Array... it involves single combination to extract additional imaging information from the phase differences. While that is very cool, at optical wavelengths (like those that Hubble uses) it would require Formation Flying to well within a wavelength of visible light (certainly impossible with any technology we have today, let alone already on the Hubble). The Terrestrial Planet Finder mission is possibly using a formation flying architecture to do infrared nulling interferometry (a different type of interferometry that allows them to filter out light from a star to see nearby planets). At optical wavelengths, it'd be nearly impossible.

Also don't forget that the larger your synthetic aperture, the more photons you need to collect to have a successful integration... This means that for very large baselines, (like the ones you suggest) you'd need *HUGE* telescopes looking for months on end.

Perhaps you meant something different?

Cheers,
Justin

Disclaimer: I work for NASA, however I write software.

They should try to park the next one as far away from Hubble as possible. There might be some interesting things we could see with such a huge effective aperture.

Hmm... Not sure what exactly you mean by this. If you're talking simple parallax-based astrometry, the hubble c an already do this effectively by taking measurements of the same stars at different points in the Earth's revolution around Sol. This gives it an effective baseline of 2 A.U. No tandem satallite in earth orbit can possibly match that.

Perhaps you're talking about aperture synthesis interferometry? This is what is used by things like the Very Large Array... it involves single combination to extract additional imaging information from the phase differences. While that is very cool, at optical wavelengths (like those that Hubble uses) it would require Formation Flying to well within a wavelength of visible light (certainly impossible with any technology we have today, let alone already on the Hubble). The Terrestrial Planet Finder mission is possibly using a formation flying architecture to do infrared nulling interferometry (a different type of interferometry that allows them to filter out light from a star to see nearby planets). At optical wavelengths, it'd be nearly impossible.

Also don't forget that the larger your synthetic aperture, the more photons you need to collect to have a successful integration... This means that for very large baselines, (like the ones you suggest) you'd need *HUGE* telescopes looking for months on end.

Perhaps you meant something different?

Cheers,
Justin

One piece of hardware (made in USSR) was able to do just that and it sent back a picture (more). I think that today we probably can fare even better, with things like aerogel insulators, etc.

P.S. But it does indeed look like Hell .

One piece of hardware (made in USSR) was able to do just that and it sent back a picture (more). I think that today we probably can fare even better, with things like aerogel insulators, etc.

P.S. But it does indeed look like Hell .

One piece of hardware (made in USSR) was able to do just that and it sent back a picture (more). I think that today we probably can fare even better, with things like aerogel insulators, etc.

P.S. But it does indeed look like Hell .

One piece of hardware (made in USSR) was able to do just that and it sent back a picture (more). I think that today we probably can fare even better, with things like aerogel insulators, etc.

P.S. But it does indeed look like Hell .

Why would NASA (or the US for that matter) allow such an expensive and high profile mission to fly on the worlds most unreliable rocket, when better domestic alternatives are available?

Because in 7 years time, it will either be the most reliable rocket - or it will have been replaced. (Hopefully)

That and ESA is a partner in the project. More Info

From NASA's about page

Did you know that every day the Hubble Space Telescope archives 3 to 5 gigabytes of data and delivers between 10 and 15 gigabytes to astronomers all over the world?

Ok, $220 million out of a budget which is projected for 2004 to be $15.47 billion or about 14%. For 3-5 GB of data per day (1.095-1.825 TB/year), this doesn't sound like that bad of a return on investment to me. Any word on how much data the new telescope will collect, and at what cost?

Here's what the surface looks like

Don't believe that sunspots can trigger power outages? Think again.

Great argument for people with their head in the trough. We need funding for specialized, proprietary hardware so we don't fall behind the Japanese. Intel/AMD CPU's aren't good enough. SUN, can't compete price/performance with Linux/Intel. NASA lost a couple of Mars probes (expensive, custom hardware), while a cheap Mars Rover mission makes it there with OTS parts. Of course, if you are aiming for taxpayer funding, your cost/performance priorities are the same as if you are spending your own money.

Heheh. I thought the place I work at, JPL, was the only place paranoid enough to have Disaster Recovery Plans.

These quakes are like, sooooo psychadelic, man.

In the vein of cool remotely controlled space thingees please don't overlook the Lunokhod 1. The Russians sent this 2000 pound robot to the lunar surface in 1970. It explored the surface of the moon for 11 months controlled by a team from the earth. Pretty ass kicking if you ask me.

In the vein of cool remotely controlled space thingees please don't overlook the Lunokhod 1. The Russians sent this 2000 pound robot to the lunar surface in 1970. It explored the surface of the moon for 11 months controlled by a team from the earth. Pretty ass kicking if you ask me.

NASA did that with the Ranger-probes from 1961 onwards. They meet with success on the 31 July 1964 at 13:25:49 UT with Ranger 7. Off course, the ruskies was first out, crashing their Luna E-1A, which hardlanded on the moon on 14 September 1959.

As for some amateurs to do the same, I think that is a few years away at the best. For one thing, no amateurbuilt rocket has yet reached orbit, allthought several groups, like the norwegian NEAR has it as a stated project.

NASA did that with the Ranger-probes from 1961 onwards. They meet with success on the 31 July 1964 at 13:25:49 UT with Ranger 7. Off course, the ruskies was first out, crashing their Luna E-1A, which hardlanded on the moon on 14 September 1959.

As for some amateurs to do the same, I think that is a few years away at the best. For one thing, no amateurbuilt rocket has yet reached orbit, allthought several groups, like the norwegian NEAR has it as a stated project.

Ah, sorry I forgot to mention in my plug that the newest version of SAP that can be downloaded is called "WITS for FIDO"... Don't let the acronyms fool you, it's essentially an older version of the same program, a flavor designed for "field tests" (simulated mars missions conducted out in remote locations on earth).

The direct link (in case you have trouble finding it) is: http://wits.jpl.nasa.gov:8080/WITS/fido/index_html /releases.

The site is a little odd at first but once you get used to it, it's pretty darn cool. Tell me what you guys think.

During the mission a much updated public version will be released, which should be much cooler. I haven't checked the permissions on downloading the fido version yet though, so I hope it works out for you.

Cheers,
Justin

Try the Visible Earth site and the Blue Marble site. Both have stunning images of day/night earth. BTW, the images map perfectly onto a 3D globe shape in your favorite 3D API, so you can create an earth visualization of your own. <rummage>Somewhere around here, I even have a Java applet I created to generate a rotating globe wallpaper.<\rummage>

Try the Visible Earth site and the Blue Marble site. Both have stunning images of day/night earth. BTW, the images map perfectly onto a 3D globe shape in your favorite 3D API, so you can create an earth visualization of your own. <rummage>Somewhere around here, I even have a Java applet I created to generate a rotating globe wallpaper.<\rummage>

Now we've been decelerating...then accelerating?

This is the thing that has been driving me absolutely crazy vis-a-vis the Big Bang theory, is that the practitioners seem to operate under the maxim:

"Keep adding terms until the data fits"

That's not the way science is supposed to work.

We've had a fair share of juggling of terms, including:

• "Big Crunch" - gravity will let the universe collapse again
• "Flat Universe" - universe will expand forever, but keep slowing down
• "Inflationary Universe" - universe expanded faster than the speed of light for a tiny moment (addressing the age and isotropy problems)
• Not sure what to call this... "Second wind universe" - universe slows its acceleration before dark energy becomes the reigning cause of repulsion

The Hubble telescope observations are getting awfully close to the predicted age of the universe. I wonder what age-of-the-universe estimate this new theory will predict; something more than 13.7 billion years?

The missing mass in the form of dark matter is, by all accounts, supposed to be mass that attracts; the inflationary universe theory depends on it for flatness. This might be another move 'around' the problem.

The Big Bang theory fell from grace for me over a period of fifteen years. While I don't subscribe to the notions of Velan, I'm curious, yet ambivalent about Alfven's plasma cosmology, there are a number of viable cosmological theories that don't have age, mass or exotic physics problems. It seems we closed the book on alternatives too soon, and are constantly interpreting data so it fits with theory, instead of breaking the back of theory on data.

Proving mathematically that you can never hit a wall must be tempered with observations of a hole in the wall and drunk in front of said wall on his back at a frat party :)

>You probably don't care about the plankton

Not particularly. According to other scientists (who are always talking facts, according to you) all our air is made by trees, so why should I care about plankton? I guess homer won't get his dime store canned specials, though.

>insects

Not at all. Hell, if it makes them migrate from the city, or keeps them from giving me West Nile, sounds great for me.

>increased cancer rates among humans

Scientists at the Fred Hutchinson Cancer Research Center in Seattle interviewed 1,606 women and found a 60 percent greater incidence of breast cancer among those who worked at night; the risk increased with the number of years on the night shift and night hours worked per week. Researchers at Brigham and Women's Hospital in Boston reviewed the health histories of 78,562 nurses and found a lower but still significant correlation: Those with one to 29 years on the night shift showed, on average, an 8 percent increase in breast cancer; those with 30 or more years showed a 36 percent increase.

LOL. These are the sorts of stats that are used to "prove" second hand smoke is deadly. An RR of 1.08 from such a small group? LMAO. You wold think the nurses themselves would be smart enough to tell them 8% means SFA.

Assuming these nurses started work at 21, by age 50, 1.9% will have breast cancer. The 8% "wow figure" brings that up to (drumroll...) 2%. And there's no way that .1% could possibly be an anomaly, right? I mean, most national polls are right 19 times out of 20, give or take 3%.

>dangerous breathing disorders during sleep

Occurrences of "disorders" or "breathing" in the article? ZERO.

>decreased attention during critical events such as driving,

What? You think people would drive better without any light? You need a study to convince me of that first before you can convince me that driving with too much light causes decreased attention.

Wait... I see... yeah, they're right! If I'm driving at night without headlights in the country, I'm driving slow and paying attention to EVERYTHING, because I don't want to drive off the edge of the road.

>Real scientists and clinicians made factual statements about problems they're seeing due to light pollution, and you simply toss it off as 'sensationalism'. Not a factual word about why they're wrong other than the implied 'it can't be'. That is the argument of a ideologue.

Well, you are right about that. Hopefully you can provide some arguments to back up why you think scientists are most always saying facts. Don't forget to back up the fact that, according to Nasa scientists, there is no "climate change".

>Your skepticism is poorly placed given the argument you presented. JMO.

Is my argument better, then? Just wondering. :-)

Ah, a perfect opportunity to post a link to my favorite NASA photo! It is a composite image called the Earth at Night. It shows the intensity of man-made light on earth. The brighness level is a facinating combination of population density and economic development.

An interesting feature is the the Nile river on the top right corner of Africa. Each bank of the river is densly populated, beyond that is uninhabitable desert. That makes it an insanely narrow bright white line in the middle of the pitch black desert.

Another interesting feature is North/South Korea. They are just to the left of super-bright Japan. South Korea is a bright square just below North Korea. North Korea is a pitch-black area. The dividing line of bright to dark is like a knife-edge. North Korea is so dark it looks like empty ocean, making South Korea look almost like an island.

North Korea and South Korea have roughly equal population density. The entire difference is due to development. South Korea is quite prosperous while North Korea is suffering famines while they allocate a crushing 30% of their gross national product to supporting the third largest army in the world (China has the largest, USA is second). North Korea says they want to "Liberate".

-

/joeyo

Realize that even as reliable as GPS is, satellites can give false information. There's a system to counteract this problem, called RAIM, but it requires 4 birds to be visible to detect a problem, and 5 to remove the faulty signal from nav calculations, assuming you have a redundant, GPS-compatible, digital barometric altimeter on board. Otherwise, you need 6 birds visible.

Guidance seems to be relatively straightforward: figure out where you are (with 95% confidence), and aim toward your next waypoint. Here's a quick overview of what that entails:

1. Determine lat/lon for you and the waypoint
2. Determine true (ground) course
3. Determine magnetic course after correcting for the aforementioned deviation
4. Determine magnetic heading after correcting for wind
5. Determine compass heading after correcting for onboard instrument magnetic interference
6. Issue commands to the flight control system to head that way

That leaves flight controls. You need to maintain proper attitude, keeping in mind that there's gonna be turbulence. In order for any magnetic navigation system to properly realigned (remember gyroscopic precession?), you need to be flying straight and level, which requires extensive compensation for unsteady flight dynamics. It's not as simple as saying "pitch up" when your speed gets too high or your altitude is too low. What if you get inverted? It can happen. Even human pilots don't do so well flying instruments only -- see the NTSB findings in the JFK junior crash. Maintaining stability and control over dynamical systems is a hard problem, which is why many colleges offer entire majors in CDS.

Disclaimer: I am a Space Shuttle enthusiast and a student pilot (hopefully, that will change in two weeks). I know that NASA have the expertise to overcome these problems, and I'm willing to give these engineers the benefit of the doubt. I wish them good weather and no system malfunctions.

I wrote the firmware for the Meteorological subsystem (MET) of MPL (known at the time as Mars Volatiles and Climate Surveyor - MVACS). It was quite depressing when MPL crashed after myself (and many others) had worked on it for so long - particularly since the MET package never even got powered on! :-(

It looks like you've substituted a scanning LIDAR for the Tunable Diode Laser (TDL) Spectrometer that we flew (or intended to fly) on MPL, and I assume (and hope) you are using a different microprocessor than we did. The UT69RH051 (the UTMC rad hard version of the 8051 microprocessor) has a very serious design flaw that we didn't discover until after flight testing had started, that causes dropped interrupts if the serial port is used in full-duplex mode. If you do happen to be using that same microcontroller, you should be aware of this advisory issued by UTMC:

UT69RH051 Microcontroller PCA & Serial Port Interrupt Flag Anomaly

If you would like to contact me for any reason, you can email me at: "SlashDot_at_spamex.com" (substitute "@" for "_at_").

Best of luck on a successful mission, and may the Phoenix rise from the ashes of MPL! :-)

-- Ron

P.S
No operating system at all (neither open source nor closed source) was used in the meteorological subsystem of MPL. The firmware I wrote was a single program that ran on the "bare metal" of the processor board, and used interrupts to effect time slicing (in effect, it was its own operating system).

I wrote the firmware for the Meteorological subsystem (MET) of MPL (known at the time as Mars Volatiles and Climate Surveyor - MVACS). It was quite depressing when MPL crashed after myself (and many others) had worked on it for so long - particularly since the MET package never even got powered on! :-(

It looks like you've substituted a scanning LIDAR for the Tunable Diode Laser (TDL) Spectrometer that we flew (or intended to fly) on MPL, and I assume (and hope) you are using a different microprocessor than we did. The UT69RH051 (the UTMC rad hard version of the 8051 microprocessor) has a very serious design flaw that we didn't discover until after flight testing had started, that causes dropped interrupts if the serial port is used in full-duplex mode. If you do happen to be using that same microcontroller, you should be aware of this advisory issued by UTMC:

UT69RH051 Microcontroller PCA & Serial Port Interrupt Flag Anomaly

If you would like to contact me for any reason, you can email me at: "SlashDot_at_spamex.com" (substitute "@" for "_at_").

Best of luck on a successful mission, and may the Phoenix rise from the ashes of MPL! :-)

-- Ron

P.S
No operating system at all (neither open source nor closed source) was used in the meteorological subsystem of MPL. The firmware I wrote was a single program that ran on the "bare metal" of the processor board, and used interrupts to effect time slicing (in effect, it was its own operating system).

I assume you mean 100,000 feet on Earth...Check out this for a discussion of the 103,500 ft. test flight of the ARES prototype. Damn cool, huh?

How much different is that concept from the Balloon The've been already talking about?

Dislaimer: I write software for Mars missions, including the 2007 Pheonix mission.

I hope they haven't recycled the imperial to numeric conversion code.

I must say I'm really tired of hearing about this every time there's an article about a mars misson. I mean, no one says "I hope they haven't recycled those overflow errors" every time an Ariane 5 rocket is lauched! Was it a stupid problem? Yes, however people seem to forget how rediculously hard it is to successfully launch a mission like this. Yes it's very easy to prevent a single mistake, but thousands of potential mistakes? Our track record with Mars probes is twice as good as the nearest competitor (Russia) and it's looking to continue that way.

Somebody want to contribute an open source alternative to them?

Look. The people working at NASA know how to write this stuff. That's not the problem. The problem is that on large scale projects like this, it's entirely possible for things like this to be overlooked... People tend to worry about the "hard" stuff rather than the easy stuff. And as for why they even have to convert units, as far as I understand NASA generally uses metric, it is the american aerospace companies that generally insist on using imperial units.

Also, Open Source is *NOT* the catch-all answer for everything! The development team I'm on uses linux for our development, and our software will be running on a lot of linux (and windows) boxes during the mission. We love open source, and even use some open libraries (such as castor) in our code as allowed (we are not allowed to link to GPL code of course).

However, I would cringe if the flight software was some open source deal... I mean, looking at the linux kernel sources, (some say it is the gem of open source) I wouldn't want to have to depend on anything written like *THAT* to handle flying in space. Great for on the ground where we can fix/replace/patch if there's a problem but... It's not cleanly designed and implemented like, say, QNX, etc. Few people alive have experience writing software for spaceflight systems, and I expect they they know just a little bit more about it than even the best of linux hackers do.

I guess I just don't understand why the parent post was modded insightful. Nothing personal, in7ane, but really!

Personally, I think there are a couple of things worth noting regarding this decision. 1st -- although $325 million is a bit "staggering", it's interesting to note that this is the first mission competition that really was a winner take all competition. 30 proposals were submitted, 4 made the finals, and then one winner was picked. I have to think NASA will be doing a lot more of this, since it's got to be more economical in the long-run.

2nd, one of the losers was the extremely cool ARES Martian Airplane proposal. I'm biased because some of the people in my lab were on the science team for that proposal, but I think it would have pushed both the scientific and engineering envelope more than Phoenix will. Was NASA being too conservative (like I think), or simply prudent? I think it's probably hard to tell right now. I sure hope ARES has a shot in 2011 if they run another Scout competition, since I think it'll remain a cool idea even then...

See this story in the Hampton Roads paper if you are more interested about ARES' s rejection/want to see a picture of the prototype.

I've heard (no, I don't have actual links to articles) that 10% of peak performance on a cluster is considered really good.

Sounds like Cray marketing articles. For example, Daniel Katz at JPL wrote in 1997:

it is possible to construct a 16-node machine with a theoretical peak performance of 3.2 GFlop/s and a typical sustained performance of 1.2 GFlop/s

The current Beowulf cluster can deliver a theoretical peak performance of about 100 Gigaflops (billions of floating point operations per second) and has been observed to deliver about 60 Gigaflops.

The observed performance was based on LU decomposition.

For sustained/peak of about 60%.

I have no doubt that one could find problems where a Beowulf cluster has 10% efficiency, but there are real many problems that are good to go on a cluster. And even if you only got 10% it would be worth it if the cluster cost 5% of what a vector computer costs. Not to mention that performance/$ on commodity hardware increases by a factor of 2 every 12-24 months. It takes years to develop a supercomputer, and they are stuck at their level of technology for several years since they are so expensive to redesign.

I think it's also worth pointing out that when a car or plane has an accident it's relatively easy to clean up. While these flights are low, space debris is a much more wicked problem. Even a loose screw or bolt is traveling at a fast enough speed to severly damage other crafts and satellites. That's why NASA tracks it all. I even saw a Discovery show where they explained that one good smash up could potentially cause a domino effect and wipe out a bunch of stuff -- even potentially creating a thick enough outer junk sphere to make future launches phenomanally difficult -- perhaps impossible. Wouldn't it be nice if we managed to trap ourselves here?
_________________

My guess is that the book is a hyped up discussion of the Wilkinson Microwave Anisotropy probe. This probe looked at minor fluctuations in the cosimc microwave background (much like COBE but with far better resolution).

The probe provided some really interesting data which has ended up posing far more questions than it answers (always the best type of experiment!). The data show that if the Big Bang model is correct that the Universe will end in heat death i.e. there will be no big crunch.

However it also shows that only ~5% of the Universes matter is "baryonic" i.e. what you would call "normal" matter. About ~20% is non-baryoninc matter and a whopping ~75% is dark energy. Currently the physics that we know about cannot account for most of the non-baryonic dark matter let alone the "dark energy". So to say that we know how the Universe is going to end when we only understand about 5% of what it actually is shows that the statement is clearly pure hype.

However this is also the reason that science is fun: we have a lot more of the Universe to understand. Either there is a lot of new fundamental physics out there for us to find or the Big Bang model predictions of the energy content are wrong. It's just best to wait until we do understand it before we make predictions.

Since it is something of an open issue, what is the current understanding of the nature of dark matter in our universe? What kinds of questions are still being investigated? What kinds of hypotheses do we have now, and what do they imply?