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Maybe because it's freaking NASA?

What's that have anything to do with it?

NASA has an OSI approved license:

• NASA Open Source License

It could probably be easier to find NASA software, and I doubt this particular software would ever be released, but there's lots of NASA software that's been released:

• from Ames
• from Goddard
• from NAS
• ... and whatever stuff's out in the wild that's not being tracked.

There's issues because much of NASA stuff is done as part of grants, and so it's officially owned by the academic / research institution that won the grant ... as such, there might be other NASA funded code that's out there, that you don't know is NASA code... at least one program (AISRP) has started a place to collect software by grantees.

I've been to NASA workshops where there's plenty of code that's being written where people would LOVE to have their software find a broader audience. At the last one, we had an hour debate on if we were allowed to release code as GPL, as that'd place restrictions on the use of the code (that derivative copies have to be open), which should not be done as the software was developed w/ federal money and as such citizens should be free to do whatever they want with it. I think someone was assigned to talk to NASA's legal department and find out what we had to do to release our code.

Maybe because it's freaking NASA?

What's that have anything to do with it?

NASA has an OSI approved license:

• NASA Open Source License

It could probably be easier to find NASA software, and I doubt this particular software would ever be released, but there's lots of NASA software that's been released:

• from Ames
• from Goddard
• from NAS
• ... and whatever stuff's out in the wild that's not being tracked.

There's issues because much of NASA stuff is done as part of grants, and so it's officially owned by the academic / research institution that won the grant ... as such, there might be other NASA funded code that's out there, that you don't know is NASA code... at least one program (AISRP) has started a place to collect software by grantees.

I've been to NASA workshops where there's plenty of code that's being written where people would LOVE to have their software find a broader audience. At the last one, we had an hour debate on if we were allowed to release code as GPL, as that'd place restrictions on the use of the code (that derivative copies have to be open), which should not be done as the software was developed w/ federal money and as such citizens should be free to do whatever they want with it. I think someone was assigned to talk to NASA's legal department and find out what we had to do to release our code.

NASA releases all kinds of code. As an example, many people in the space science community rely on SPICE from JPL's Navigation and Ancillary Information Facility, and you can play from home. I think the newest version of Celestia has a CSPICE interface to get extremely accurate planetary positions and spacecraft pointings into it.

The funny thing? The efficiency is atrocious and the fear quite legitimate.

As for the fear: check out what NASA has to say about hydrogen. Some excerpts:

Ignition:

"Hydrogen-air mixtures can ignite with very low energy input, 1/10th that required igniting a gasoline-air mixture. For reference, an invisible spark or a static spark from a person can cause ignition."

"Although the autoignition temperature of hydrogen is higher than those for most hydrocarbons, hydrogen's lower ignition energy makes the ignition of hydrogen-air mixtures more likely. The minimum energy for spark ignition at atmospheric pressure is about 0.02 millijoules."

----

Mixtures:

"The flammability limits based on the volume percent of hydrogen in air (at 14.7 psia) are 4.0 and 75.0. The flammability limits based on the volume percent of hydrogen in oxygen (at 14.7 psia) are 4.0 and 94.0."

"Condensed and solidified atmospheric air, or trace air accumulated in manufacturing, contaminates liquid hydrogen, thereby forming an unstable mixture. This mixture may detonate with effects similar to those produced by trinitrotoluene (TNT) and other highly explosive materials"

"Explosive limits of hydrogen in air are 18.3 to 59 percent by volume"

"Flames in and around a collection of pipes or structures can create turbulence that causes a deflagration to evolve into a detonation, even in the absence of gross confinement."

(For comparison: Deflagration limit of gasoline in air: 1.4-7.6%)

Leaks:

"Leakage, diffusion, and buoyancy: These hazards result from the difficulty in containing hydrogen. Hydrogen diffuses extensively, and when a liquid spill or large gas release occurs, a combustible mixture can form over a considerable distance from the spill location."

"Hydrogen, in both the liquid and gaseous states, is particularly subject to leakage because of its low viscosity and low molecular weight (leakage is inversely proportional to viscosity). Because of its low viscosity alone, the leakage rate of liquid hydrogen is roughly 100 times that of JP-4 fuel, 50 times that of water, and 10 times that of liquid nitrogen."

----

It also covers how hydrogen likes to pool under roofs and overhangs, and that buildings containing hydrogen or hydrogen pipelines should have roofs designed to be blown away, as well as extreme caution on spark suppression. It also talks about how hydrogen can enter pipes and follow them to their destinations, and pool there.

As for efficiency, the efficiency of a hydrogen economy is atrocious. Don't take my word for it; listen to peer review. Check out the convenient chart. Electric cars have three times the efficiency of hydrogen cars from a given power source. Even if your power is renewable, this tremendous efficiency difference can't be ignored. This means, for hydrogen, three times the land covered in solar cells, three times the dammed up rivers, three times the coastline covered in wind farms, and so on.

Hydrogen is a complete waste of time. A fuel cell stack will weigh down and take up space in a typical vehicle as much as a modern li-ion battery stack, only give similar range, cost ten times as much, have less room for price improvement in fuel cell costs versus battery costs (platinum playing a big role in this), have a shorter lifespan (again, compared to modern automotive li-ions like phosphates, spinels, titanates, etc, not laptop batteries), more temperature sensitivity (yes, you read that right; modern li-ions are often good to -30 or less

Partially correct. Pure oxygen is not poisonous. Medical oxygen is one example. The Apollo missions also used high oxygen concentrations. It is however, extremely dangerous to be in a high concentration of it. The slightest static discharge can create an inferno. When deep sea diving, under high pressure; it can become toxic ( nitrogen also has effects: see nitrogen narcosis). I hadn't heard about oxygen increasing the rate of aging. The most relevant result google produced was this . Anyone have more insight on this?

You are correct about oxygen not being flammable by itself. It requires some sort of fuel to actually undergo redox. The fire triangle is an easier way of thinking about it.

http://www.nasa.gov/missions/highlights/schedule.html

There's the page that details the last launches in case you wanted to take the chance and see one. I've never seen one yet, but I'd like to. *gotta hurry*

The soviet capsules are there for emergency evacuation of the station. The problem of trying to leave a shuttle up there just in case something happened is that the shuttle is not designed to sit up there for extremely long periods of time. By the time something happened where they might need to use the shuttle to come back down any number of systems would no longer be working as expected.

The system needs to be retired and replaced with a true single stage to orbit vehicle. They had one in development, the Delta Clipper, but it was cancelled shortly after a failed test flight. Up to that point it worked well. And the failure was due to a landing leg not extending correctly.

http://www.hq.nasa.gov/pao/History/x-33/dc-xa.htm

Arecibo's dish has been used to image asteroids. Don't be so quick to shut it down if that's what you want to look for.

I suppose Mars is in the news now with all those stories of water being found. But, really, who cares? What practical benefit does that have for those of us who live on Earth?

Besides incresing our common knowledge of the universe we live in, or the new technologies developed by the space program? Saying "i don't care, i live on Earth" is like saying "why would i ever leave home? the fridge is stuffed."

Science brings knowledge. And knowledge is one of the most intangible assets human kind posseses, but perhaps the most important. Think of it as investing in your future.

It's not as geologically inactive as had been thought, the dust devils are nasty devils, and very little is understood about the polar regions.

I don't know what you've been hearing, but first couple of things are bunk. The spacecraft takes a big jolt when it lands. Sure it doesn't have all the instruments out then, but most earthquakes are as insignificant on Mars as they are on Earth. Second (googling around a bit), I find that the probe doesn't point at Earth. It has a non-directional UHF antenna with hemispherical coverage of the sky. This antenna allows communication with two satellites currently in orbit around Mars. That's how it communicates with Earth.

Second, the dust devils aren't nasty because the martian atmosphere is no more than 1% of Earth's atmospheric pressure.

NASA has grown poorer, is rushing these missions as much as possible, and can't afford to build systems as robustly as they should, but more importantly, missions have become tougher and involve more hazardous environments.

My take is that NASA's approach to science missions is deeply flawed. Any serious exploration of space is going to require space probes with development cycles of say four years or less. There are two big problems with longer development cycles. First, the longer the project, the more likely that it'll be redesigned, have funding trouble, or be cancelled. If you can get the development to launch in under 4 years, then you can launch missions under the same administration. Second, long development cycles greatly reduce how fast you can react to new information. If you find out something interesting but not currently in the schedule, it's unacceptable to have to wait another ten years or more before another probe can be sent to investigate this. You are wasting a lot of peoples' time.

Then we get to robustness. Currently, NASA launches expensive one off missions that are pretty robust as a single unit, but don't take advantage of economies of scale. My take is a few highly robust missions are more expensive for the data gained and dollars spent than a large number of cheaper, less robust missions. And that's including the higher failure rate of the less robust missions. There are various tricks. Instead of making one or two probes, you can make three to ten. Instead of building probes from scratch, work on developing a suite of "off the shelf" infrastructure and instruments so you can put together a probe for a particular mission fast. Also, I think that a counterintuitive result is that an organization which launches a lot of cheap probes is eventually going to get those to be more reliable than the organization which continues to launch a few, highly "robust" probes. The reason is that a lot of probes means a lot of exploration both of failure modes for those probes and data on the harsh environments that these probes end up in. While the "robust" probe makers don't know what they're up against and have to overengineer their probes.

If you were standing on that orbiting pulsar, how long do you think your watch would read [relative to an Earth observer]?

There are two kinds of time dilation. There is the time dilation which comes from the velocity of the orbiting pulsar. If the pulsar system is at rest with respect to the Earth, this will be small, since the pulsar's orbital speed is pretty low compared to the speed of light, unless its orbit has decayed and it's about to ram into its binary partner.

There is also gravitational time dilation, due to the gravity on the pulsar's surface. That would be on the order of 10-20% slowdown in time; see here (PDF). Not as huge as you suggest, but not negligible either.

I think that Gravity Probe B has the most perfect spheres and they are much smaller that the Kilogram sphere.

Kilogram Silicon Spheres
"If you were to blow up our spheres to the size of the Earth, you would see a small ripple in the smoothness of about 12 to 15 mm, and a variation of only 3 to 5 metres in the roundness"

Gravity Probe B Spheres
http://www.nasa.gov/mission_pages/gpb/index.html
"If these ping pong-sized balls of fused quartz and silicon were the size of the Earth, the elevation of the entire surface would vary by no more than 12 feet"

But then we're talking about an agency that flew Space Shuttles for 40 years.

The first Space Shuttle flight was a test of Enterprise in August 1977. The first actual mission was in April 1981 with Columbia . Unless I've dropped through some kind of freaky weird timewarp, it's only been 31 years.

"Not a single solid rocket booster was ever lost on the space shuttle (they are all re-used) and the design for the ARES is almost identical."

I'll say it in one word...Challenger.

From what I recall the loss of the orbiter was caused by the failure of the solid rocket booster. Subsequent to the explosion of the shuttle both solid boosters were ordered to self-destruct. By my count that is two that were lost during flight.

Now being really nit-picky, if we count any flight related damage that results in a SRB segment being unusable before it's rated lifetime expires as a partial loss, I am sure the numbers will start to add up. During the course of the Rodgers Commission investigation information indicating that other shuttle flights had SRB joints that experienced burn through of the O-rings. On one flight the burn through was about 33% the radius of the O-ring. These segments were sent back to Morton-Thiokol for refurbishing. But that does not mean they actually flew again, they could have been too damaged to refurbish. We do not know. I doubt anyone at NASA really knows. To me, that would be the loss of a segment. If you add up the SRB segments that could not be refurbished, for whatever reason, I am sure you would get the equivalent of several more SRBs that were lost due to flight activities.

While you make several good points, simple errors like this ruin your credibility.

It sounds like you need to subscribe to the NASA video podcasts.

I highly recommend This Week @ NASA, because they don't just talk about the shuttle, but all the missions & experiments going on in the agency. The Shuttle & Station podcast has all your takeoff & landing footage, usually within a day of it happening, and in addition to the usual footage, you get odd stuff like the video of the launch from a camera on the fuel tank.

If you really want to be blown away, get an HDTV and subscribe to DirecTV with HDNet. They broadcast every shuttle launch & landing within a few days of it happening, and it's an hour long show with footage of Mission Control, and interviews up to the big moment, and it's all broadcast in 1080i with digital sound.

It does contain news - the news that the current melting rate of the polar ice is the highest recorded.

Yah the highest recorded in what? The 100 years max we have been keeping tabs on melting polar ice?

Not even that. Since 1979. I am also completely underwhelmed.

Yea thanks that's great; I'm quite rusty on history. Wouldn't have thought of that.

I don't believe we're in much danger from Antarctica. It's significantly cooler there than the North pole. Consider:

At the South Pole (Amundsen-Scott Station), the average temperature of the coldest month (August) is approximately â"76 F (â" 60 C), and the average temperature of the warmest month (January) is â" 18Â F (â"28.2 C). Records go back at the South Pole to 1957. At the North Pole, long term temperature records aren't available, but in 2003 a live weather camera and an unmanned weather station were installed on the sea ice. During the last 3 years, the daily temperatures have vacillated between about â"40Â F (-40Â C) during December and January to a little above freezing (0Â C) in June, July and August. The seawater below the ice provides enough heat to keep winter temperatures from falling much below about â"40Â F (-40Â C). I suppose all the activity of Santa and his mischievous little helpers, plus 8 or 9 tiny reindeer might be responsible for boosting the temperatures here a little too.

Taken from NASA.

Aren't there valid arguments that say that this is just a cyclic phenomenon linked to solar activity?

No. Increased solar output appear to only account for a small portion of the increase in temperature. Of course some of the 10,000s of scientists involved may by liberal, so we can just ignore them...

Ever notice how when you have ice in a cup of water, the level doesn't rise when the ice melts? Only the ice sheets in Antarctica (which is on the south side) which sit on top of land will cause sea levels to rise. And unfortunately they are melting at an alarming rate

Also, I'm highly skeptical of the claim that computer enthusiasts coming out of MIT, no matter how new, are attractive.

Really? How about this young woman? http://coop.jsc.nasa.gov/biography/jordann.html
Or these ladies? http://web.mit.edu/madmatt/Public/Pics/cheerbig.jpg
Or if you like a little controversy with your sexy, how about one of the most gifted (and hot) young computer enthusiasts I know - http://bea.st/sight/archive/08/05/star/

For the record, Rob Ferl was quoted in an old CNN article recently cited in a previous Slashdot comment

"I have no doubt what we can get plants to survive on Mars. When we do, we will have shown that Earth-evolved life is capable of thriving in distant worlds, and we will have set the stage for human colonization," Ferl said.

Looks like he was right on point, except it might just be TOO easy to grow plants there. This data should help decide how to further modify plants for the 'next' mission opportunity!

OK! I was hoping someone with high speed internet access would do this for me, but I did it. NASA says that much of Mars' atmosphere was lost to pressure from the solar wind, but "[...] solar wind erosion was likely much more effective in the past than it is today." Some believe that Mars' atmosphere was lost mostly due to collisions from a variety of potential impactors. Apparently you can or once could take a class at uoregon which would teach you that there was insufficient temperature for [Martian] water to remain as a liquid, so it froze out leaving CO2 as the primary component in the atmosphere. Which is OK, that's an atmosphere! We want it for warming (CO2 is great) and for providing pressure so that we can survive with an air mask (for which purpose it would be fine.) I mean, an oxygen atmosphere would be dandy, but any atmosphere would be an upgrade. However, it might also have been 7.5 bar of CO2 when Mars was young, which would be a bit excessive for our purposes. Actually, .5 bar would probably do the job, although it would certainly limit the value of suction-based pumps in a non-pressurized environment...

NASA Mars Phoenix Lander

NASA has photos of water on Mars dating back over 3 years ago here

I'm glad someone else remembers this. For you whippersnappers in the audience, Nixon announced the Space Shuttle program in 1972, effectively destroying the existing Apollo/Saturn structures put in place by JFK. There was much fanfare about "re-usable" this and "return-to-earth" that, but in the end the Saturn V was replaced with a much-less-capable vehicle (Shuttle payload capacity is about 1/4 that of a Saturn V, and it's not capable of leaving LEO.) Disassembling JFK's legacy was a political priority for Nixon, and he used the Shuttle as a vehicle to do so [pun intended.] Folks at NASA who pointed out the lack of Emperor's Clothing were rapidly dismissed. Nixon did irreparable harm to NASA's culture, resulting in the risk-averse bureaucratic behemoth we have today.

> Hopefully they are right about it.
Of course they're right about it, they have solid photographic evidence.

Finding water was one of the key goals of the Phoenix mission.

That is a bizarre statement. Large quantities of ice have been observed in numerous ways already. Even the Viking lander observed water frost directly in the 1970's:

http://en.wikipedia.org/wiki/Viking_2

http://www.solarviews.com/cap/mars/frost.htm

That frost sublimated just like this ice did.

Here are other observations:

http://science.nasa.gov/headlines/y2002/28may_marsice.htm

Here you can see a frozen crater lake:

http://esamultimedia.esa.int/images/marsexpress/210-010705-1343-6-co-01-CraterIce_H.jpg

http://www.esa.int/SPECIALS/Mars_Express/SEMGKA808BE_0.html

Not only is that ice, it may actually be an outflow.

What makes the results from Phoenix exciting is that the actual experiments that Phoenix is supposed to perform depend on having landed on ice. But finding ice somewhere on Mars is not a surprise.

See: Apollo 1.

Here's a picture from the phoenix lander of water on Mars: http://apod.nasa.gov/apod/image/0504/WaterOnMars2_gcc.jpg

Yes, we've even mapped the ice at the poles. But this is still important for a couple of reasons.

First, it's confirmation that the white stuff at the poles really is ice (and not some unknown martian substance that just looks like ice).

Second it means that the lander is digging in the right places to find all of the interesting stuff that goes along with water. It's tremendously interesting to discover whether there's carbon-based fragments in the water (suggesting life did or could exist) and to figure out what else is in the water.

This was proven SO long ago.

It is pretty well established that he did in fact invent them in 1945 - and although many people lament the fact that he never bothered to file for a patent - he would often retort that even if he had, the patent would have long expired before the first commercial geostationary communication satellite was launched (Intelsat 1). The first geostationary satellite of any type was the Syncom 2.

It is pretty well established that he did in fact invent them in 1945 - and although many people lament the fact that he never bothered to file for a patent - he would often retort that even if he had, the patent would have long expired before the first commercial geostationary communication satellite was launched (Intelsat 1). The first geostationary satellite of any type was the Syncom 2.

Seriously...

Here is a link to a review of the idea, the site is run by some well published climate scientists who have contributed to the IPCC reports over the roughly two decades the project has been running. Their conclusion regarding the application of the idea....

"I would put ocean fertilization on the avoid list, along with planting trees. It's too hard to pin down the actual amount of CO2 removed from the atmosphere by your actions. It's also not a long-term solution, since the ocean leaks. Humankind would have to keep fertilizing the ocean indefinitely in order to preserve the claimed CO2 drawdown. If you're concerned about climate change, build a windmill. Ocean fertilization does not seem to me suitable to be the basis for a reliable financial commodity, or a practical tool for geo-engineering climate."

I also happen to agree with the tree thing when it comes to implementing a cap and trade system for CO2. As he says himself elsewhere, trees are worth preserving for other reasons.

I don't dispute the fact that iron dust can increase phytoplankton but I certainly dispute the claim that dumping iron into the ocean is a practical solution to AGW. Unless of course the iron is in the form of a machine that can harvest power from the tides, winds or waves of the ocean.

If you haven't done so I would suggest you read (or at least spend a half hour to skim) the IPCC reports, particularly the latest SPM and the attribution graph. (Note: The IPCC does not come up with it's own science, rather it is a review of the published litrature. All reviewers and authors of the reprots are published scientists in a relevant field, every national science body on the planet is represented by a scientist. IMHO getting this many boffins and scientific institutions to agree on anything would tend to indicate the reports are on the conservative side.)

"Why do people get so defensive about these topics?"

Personally? I don't like to see people taken for a ride due to deliberate misinformation, I also don't like the outright hostility toward "environmentalists" from the US administration that goes unquestioned by many of it's citizens. The only scientific debate I have witnessed that comes close to the political perversion of the AGW debate is the tabacoo debate that went from the 60s thru to the late 80's. In some instances it's even the same people spreading the bull$hit. I realise AGW is not the only problem in the world, nor is it the worst. But it's one of a handfull of serious threats to ALL of us and we can choose to do something sensible about it. My personal choice for the number one threat? - ignorance.

This is the idea behind the "Space Interferometry Mission, PlanetQuest". You don't even need a very long baseline to make significant progress. If it goes forward (it has a troubled political history with NASA), it would be placed in an orbit around the Sun, trailing the Earth.

Here is what JPL says of the about the techniques used to find planets:

http://origins.jpl.nasa.gov/library/exnps/ch04_1.html#4.4

Based upon this I will offer these answers to your questions, though with the caveat that I am not an astronomer.

Astronomers are looking for perturbations in a star's light output intensity or in its lateral movement relative to other known stars.

What does this mean?

If a planet crosses the boundary between the star and us it should dim the light output. If this happens repeatedly at predicted intervals, a planet has been discovered. Similarly, if the star "wobbles" in a predictable manner, the gravity of the planet can be said to be "tugging" at the star. In both cases, one can determine (with a large margin of error) the mass of the planet by noting either the drop in light intensity or by comparing the known mass of the star against it's relative gravitational shift (wobble).

So: your question is, why do the planets thus discovered have relatively short orbital periods? My speculation is that it's much easier to determine short periodicity than long periodicity, thus outer planets orbiting remote stars should take far longer to confirm due to the need for lots of redundant data collection to confirm a finding.

I was rather more impressed by these silver whiskers... looks like it grew a whole beard!!

Nasa also has information and research into this: http://nepp.nasa.gov/WHISKER/

According to NASA, research has shown that you need at least 3% lead in the solder alloy to prevent whiskering.

There are conformal coatings which can delay the effects of tin whiskering, but that's all they do. They do not prevent the tin whisker from forming.

There are many tests out there which test for strength of the connection. But very few test for whiskering. We need to be careful when discussing this subject. Oh, and one other thing: the new solder alloys are not compatible with the older tin plated parts. This issue has turned the market in to one great big experiment.

At the end of the day we don't really have much of a lead problem with electronics. Now, the RoHS folk have turned this relatively minor ecological problem in to a major headache for the general public. I hope you weren't expecting that pacemaker to last more than three years....

I was rather more impressed by these silver whiskers... looks like it grew a whole beard!!

http://nepp.nasa.gov/WHISKER/photos/pom/2003sept.htm

These are completely immune to tin whiskers.

I would be supprised if silver grew tin. Technicaly you are correct, Silver doesn't grow Tin whiskers.

Silver whiskers is a real problem in industrial locations where Florene is present. The circuit breakers, buss bars and other industrial power components are prone to growing Silver whiskers. Failures are the result of increased contact reistance causing failure from overheating and arc flash failures from arcs initiated from the short. Both are serious failures.

Refrence with photos, Of course:
http://nepp.nasa.gov/WHISKER/other_whisker/silver/index.htm

What's interesting is, nobody seems to draw a parallel between spikes that appear when clear water is frozen and tin whiskers.

I've been seeing heat related issues, some component manufacturers have removed the lead but their parts do not hold up to the heat required for no-lead reflow and wave soldering. We're having parts not only fall out during testing but getting field failures back. This is for non-electrolytic capacitors a ceramic surface mount type and a through hole mylar type.

I've been seeing some units that were done with no-lead less than a year ago where parts are falling off the board. These were some of our early no-lead units so they'll just warranty them and replace the boards.

As to the tin whisker problem NASA has a lot of information on it.
http://nepp.nasa.gov/WHISKER/

But I can't see where they're following their own advice if it means it's a 'show stopper'
http://www.nasaspaceflight.com/content/?cid=4537

>the only metal I've heard of as being whisker free is lead
Oh really?
http://nepp.nasa.gov/WHISKER/other_whisker/index.htm#pb

Where was it referred to as a "NASA spacecraft"? I looked over the summary and the press release, and it was always referred to as the "Ulysses spacecraft". The closest phrase was "The spacecraft was provided by ESA.", or references to the NASA/ESA "mission" or "project" not "spacecraft".

It's an ESA spacecraft (built by "Dornier Systems, Germany (now Astrium)"), with a mix of US & European instruments, launched by NASA (shuttle + Boeing + McDonnell Douglas), operated from NASA (JPL) by a joint NASA/ESA team.

Most NASA press releases I've seen tend to mention the manufacturer, good or bad, if it's a US company. When it's European, mentions of the contractor are a lot rarer, though Italy seems to be good at getting its name in there (probably because the US has had some construction contracts with them, outside of their ESA agreements). For example, looking over the Mars Polar Lander news release archive, the attributions to NASA vs contractors seem similar to MER and Phoenix press releases.

Hm, I actually derived that completely wrong and had the wrong result for a flat shield, so why did my numbers match up...

http://solarprobe.gsfc.nasa.gov/solarprobe_spacecraft.htm:

The spacecraft's most prominent feature is the Thermal Protection System (TPS), comprising a large 2.7-m diameter carbon-carbon conical primary shield with a low-conductivity, low-density secondary shield attached to its base.

So the shield is actually a cone instead of flat like the article shows. And it just randomly happens to have the right proportions to make my numbers look right.

It takes *very little* current to short a FET gate, i.e. microamps or less. Indeed, compare the geometry of these whiskers to the tracks etched on silicon. Not every bit of metal exposed on a PCB will carry current large enough to fuse these whiskers before they cause disruption. Furthermore, chip-scale assembly techniques likes BGA will give you plenty of areas with large blobs of solder within convenient whisker distance of each other.

As referenced in another comment, NASA Goddard Space Flight Center does indeed seem pretty concerned:
http://nepp.nasa.gov/WHISKER/