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http://antwrp.gsfc.nasa.gov/apod/ap010929.html

With the planets past mars being gas or ice, the 4 inner planets being rock and iron, WHY would anyone think that the sun is all gas?

If the gas elements were spun/pushed to the outer limits of our solar system and the heaver elements combined to form the inner planets, if the sun was all gas it should be out where Jupiter is??? Why can't people understand that???

I only made it through high school and just barely and I can freeking understand that.

Now the sun may have a hydrogen and heilum shell, but Mercury, Venius, Earth and Mars have rock outer shell. Mars itself would have an atmosphere if it had a magnetic core to protect it from solar wind.

Why is it so hard to understand the the sun is iron?????

Nathan

From a NASA HQ release [March 2005]:
The winners of each initial 2005 challenge will receive $50,000. A second set of Tether and Beam Power challenges in 2006 are more technically challenging. Each challenge will award purses of $100,000, $40,000, and $10,000 for first, second, and third place.

Read the entire release here .

It will be interesting to see if NASA increases the difficulty of the challenge as planned, or if the decide to keep at at the first year level of difficulty since nobody was successful this year.

Yes? Please go on.

I also never took a "plasma" class, only those standard classes in EM, Thermo, Stat Mech. What is the claim of the engineers? Where are we ignorant?

That link again... Also this, evidence in hand that interstellar current flow, in the mode Alfven predicted, is really occurring. When evaluating models for (e.g.) Eta Carinae, you have two problems: (1) how can you get all that stuff to happen using just gravitation, fusion, and shock waves, and (2) how can you get all that plasma (not just "hot gas") that suffuses the whole system to have no effect at all? When you're only talking to other astrophysicists who also know nothing of plasma dynamics, you get to skip (2), but it makes astrophysical speculations look pretty comical from out here.

Plasma has interesting dynamics because its positive charge carriers are 2000x heavier than the negative carriers. Furthermore, they're often mixed in with neutral matter (commonly at 10^-4) that gets entrained. Motion in real plasmas is subject to dozens of nonlinear instabilities. All this makes maintaining electrical neutrality complicated, and not infrequently impossible. The mathematics is intractable, so it's often necessary to fall back on laboratory phenomenology and numerical particle-in-cell simulations.

Nobody promised the real universe would be easy to model. Pretending leads you down a rabbit hole. Your astrophyics colleagues will happily follow you there, but that's not science.

NASA was given a chance to clean up its act with The Launch Services Purchase Act of 1990 which required them to procure all launch services from commercial sources.

So in other words you'd would rather that they stoped sending people in to low earth orbit 15 years ago because there were no commerical options for sending crews to any orbit? Guess what, there still isn't any private company that can launch a human being into orbit and return them safely, not even Burt Rutan's. I think that will change in the future, hopefully the near future. However it hasn't happened yet, so don't talk like NASA is ignoring two dozen potential orbital carriers.

Micheal Griffin has stated before that he would support private launch companys by paying for there services when it makes sense. In the same address he also added that he felt it would not serve the taxpayers' interests to rely exclusively on private launches in the forseeable future. But you don't have to take my word for it, check-out his Remarks Before the Space Transportation Association.

... was disqualified for "inappropriate" elevator music... Under testing situations, all of our patients (read: monkeys, elderly, humans, and fish) were driven insane, then promptly driven sane, then insane, then sane, and so forth during the 62.5 mile elevator ride finished. After the tenth go around we decided the cost to hosing out the compartment filled with bile, blood, and bits of hair were not worth the cash prize. So it goes. Additionally, the PSP battery life wasn't sufficient to stave off elevator-maddness either. http://trs.nis.nasa.gov/archive/00000377/01/tm1085 37.pdf

That is a myth. The space program was responsible for a lot more than Tang and 'space pens'. Then again, there are things that you can't put a price on, such as the need for mankind to go to space.

The idea of a tether system has yet to be successfully demonstrated.

I'm personally in favor of them utilizing some wasted external tanks to create a sort of octagon around a central propulsion tower that could be spun for anywhere from the .3G for Mars local G to 1G for the return home.

The biggest problem foreseen with any rotation scheme is of course the coriolis forces whereby your head experiences an amount of gravity fractionally different than your feet. This gives new meaning to the term light headed.

This looks like a fake to me: http://www.nasa.gov/externalflash/cev/CEVedit2.mov

I'm sorry, I should have been clearer. We see galaxies whose redshift suggests (according to the standard interpretation) that they're 12 billion light years away, and thus formed in the first billion years after presumed recombination, made of stars that had to be 4 billion years old at the time. I.e., 12+4 > 13.7.

As an astrophysicist, I'd like to be an apologetic for the standard cosmological model ...

That's to your credit. Most astrophysicists would prefer to pretend that, e.g., quantized redshift as referenced to the CMB rest-frame in low-redshift galaxies, or to angularly-nearby low-redshift galaxies in the case of high-redshift galaxies and quasars, don't exist. Most would prefer to pretend that high-redshift quasars (e.g. z=2.11) physically in front of low-redshift opaque galaxies (e.g. NGC 7319, z=0.0225) don't exist.

Most seem to prefer to pretend that MHD conditions apply to the dynamics of interplanetary and interstellar plasmas, so they can pretend it's all just "hot gas". I have a private e-mail from a well-known astrophysicist asserting, without apparent embarrassment, "Plasmas behave as ideal gases on scales much larger than the Larmor radius of motion around the magnetic field." He admits most graduate students in astrophysics, still, never attend a laboratory class on plasma dynamics, and just work artificial problem sets using the MHD approximation.

I hereby claim longest dupe period yet! I reserve the right to submit this article 5 years hence.

I guess the /. search function really is a stinker. I should just use Google for this sort of thing. Blame APOD, it was their photo today!

Just adding MALE names would give you atleast 20 more easy names. Why are storm names female? I suppose it comes from the old days when only men worked as sailors , and thus named everything female.

Certain things on a space probe do not particularly like being contaminated, such as ohhhh I don't know, lenses?

When someone picks beautiful colors, the photo becomes partly art.

The implication is that people wouldn't be interested in straight science.

True, but scientific photos are often colorized or frequency-shifted for valid scientific reasons. The human eye and the brain behind it are very good as spotting complex patterns in visual data. So mapping data into a 2-D image in the human visual range can be a fast way to spot the interesting features (that may then be analyzed in more detail by software).

Thus, the most informative weather-satellite pictures are usually the "false color" images that map infrared into our visual spectrum. A true-color picture just looks like grey cloud, but the frequency-shifted IR images can impart a lot of information very quickly.

Similarly, Saturn is mostly just an off-white spheroid to our eyes, due to high-altitude haze. But in other frequencies, the planet is as complex as Jupiter. So IR and UV photos are routinely shifted to make images that can be understood visually.

In the last week, we've seen some interesting new IR images of the Andromeda galaxy. Combined with earlier UV images (linked to by that page), we can easily see features that don't show up in visual-range images. Together, the infrared, visual, and ultraviolet images are much more interesting and informative than any one alone.

I have read the article and I found no explaination at all about how the clock can calculate the local time including the leap second. Ok, the clock have a synchronization of the earth rotation using the sunlight, but this in no way synchronized to the local time. First current local time is an offset of UTC and UTC is an offet to TAI and TAI is a averge of many atomic clocks, so the basic of our local time is not astronomic, but atomic (http://cr.yp.to/proto/utctai.html). This clock can be a impressive model of the astronomic motion, but this is the wrong way to tel the local time. Second, even for the astronomic motion I have doubts, since I never see a paper telling that the earth axis motion can be know for 10'000 year. But you can find papers that tel exactly the opposite: this motion is largely unpredictable as now for a such long time. See this URL about how complexe is the earth rotation axis http://mb-soft.com/public/precess.html and this URL about why this is impossible to predict at full precision this movement http://www.cv.nrao.edu/~rfisher/Ephemerides/earth_ rot.html. Did you know that such bulltins exists ftp://maia.usno.navy.mil/ser7/iersexp.sup ? Last, did you realiste that the local time is an human concept that have radicaly changed in less than one century ? How can someone assert that this will not change in 10'000 year ? Juste an exemple: the Asian earthquake end last year did have an observable impact on the earth roation, see http://www.nasa.gov/home/hqnews/2005/jan/HQ_05011_ earthquake.html. So keep in mind this basic facts: 1) astronomic motion is unpredictable in full precision for long time; 2) local time in based on atomic observation plus offset to keep it compatible with astronomic observation, not the opposit!

I also heard a story of a pair on a shuttle having a relation and getting married shortly after the flight. Apparently NASA wasn't told before and was not happy. (Might have been the same couple.) And of course the rumours that some Russkies sacrificed themselves for science. I can't find a reference for both stories unfortunately.

Google Moon is here, although it only shows the area of the Apollo landings. There was a Slashdot article discussing it, it was developed for the 36th anniversary of the first moon landing. What I would like to know is, if we were able to do Apollo (and Mercury AND Gemini) in less than ten years, why 1. haven't we been back in over 30 years 2. aren't we going to go back for another 13 years?

Google Carnot efficiency

Googled. The formula is:

Efficiency = 1 - Tc/Th, where Tc is the temperature of the cold end of the cycle, and Th is the temperature of the hot end . That is, effeciency equals one minus the cold temperature divided by the hot temperature. For a steam engine, the hot temperature would be the temperature of the incoming steam, and the cold temperature would be the temperature of "cold" steam exhaust.

There is nothing here saying, the spent steam can not be colder. The fact that it escapes hot enough to heat a building, means it could've produced more electricity -- as is obvious from wider-known Physics. There may well be engineering reasons making this target unreachable with the level of technology at the time of the particular plant's design, but I do no see a theoretical reason. "Carnot Efficiency" certainly is not one...

Unfortunately, testing and verification does not insure 100% "correctness". Some problems are only likely to be found via code inspection (or in some cases, more efficiently by requirements, architecture, and design reviews - but ultimately, flaws upstream are reflected in the code).

NASA works pretty hard at test and verification of its software, but still missions, such as this or this (pg 26) [PDF warning], have failed due to software problems (bugs and/or design flaws) or process errors. Recall also the little division problem on Pentium chips which was caused by a lookup table having a few entries downloaded incorrectly - and Intel surely did a lot of testing, yet missed this flaw.

I don't know anything about how breathalyzers work. However, it would not surprise me to see that various calibration information (perhaps "known sample", factory calibration of internal sensors, and/or calibration to "zero"), environmental factors (temperature, humidity, and/or barometric pressure), and tested sample information (volume and/or temperature) are factored into the final "BAC" number displayed. There may also be lookup tables (which may have been downloaded incorrectly) involved as well. It is likely impossible to test all combinations of factors (since, if nothing else, doing so would probably result in the product not shipping for many, many years - by which time it would be obsolete).

For these reasons, I don't think that it is possible to say that a breathalyzer is "tested and verified". Since the freedom of thousands of individuals every year depends on the correct operation of breathalyzers, it seems like good public policy to open up the source code, circuit designs, and specs for viewing by all. Note this would not require relinquishing copyrights or patents on these materials.

Unfortunately, testing and verification does not insure 100% "correctness". Some problems are only likely to be found via code inspection (or in some cases, more efficiently by requirements, architecture, and design reviews - but ultimately, flaws upstream are reflected in the code).

NASA works pretty hard at test and verification of its software, but still missions, such as this or this (pg 26) [PDF warning], have failed due to software problems (bugs and/or design flaws) or process errors. Recall also the little division problem on Pentium chips which was caused by a lookup table having a few entries downloaded incorrectly - and Intel surely did a lot of testing, yet missed this flaw.

I don't know anything about how breathalyzers work. However, it would not surprise me to see that various calibration information (perhaps "known sample", factory calibration of internal sensors, and/or calibration to "zero"), environmental factors (temperature, humidity, and/or barometric pressure), and tested sample information (volume and/or temperature) are factored into the final "BAC" number displayed. There may also be lookup tables (which may have been downloaded incorrectly) involved as well. It is likely impossible to test all combinations of factors (since, if nothing else, doing so would probably result in the product not shipping for many, many years - by which time it would be obsolete).

For these reasons, I don't think that it is possible to say that a breathalyzer is "tested and verified". Since the freedom of thousands of individuals every year depends on the correct operation of breathalyzers, it seems like good public policy to open up the source code, circuit designs, and specs for viewing by all. Note this would not require relinquishing copyrights or patents on these materials.

you'll probably need some additional energy to power the communication equipment. A solar-powered plane would already have solar cells for that.

As has been said, Russia has had a number of pretty successful projects. How much can you say about NASA recently? The space shuttle project is falling apart, they're planning repeating Apollo for whatever reason, there were a bunch of failed Mars missions, Hubble's future looks bleak, etc.

On the other hand, there have been successes some wildly so in recent times. First, the Mars Exploration Rovers are still hanging in there and producing worthwhile data. Second, Gravity Probe B, has succesfully completed its mission. And that's just the stuff that was successful this year.

Failures get more press than successes, for much the same reasons disaters are reported more heavily than the fortunate occurances.

Problem? That's the whole reason the different TLDs were created.

Not only can you have tea, but you can drink (eat?) it with chopsticks!

You said:
if you want better computers, research better computers
Why should we invest in 'better' computers- what is it we want them for, what problem are we trying to solve? If you mean faster computers and more memory, then that's interesting, but not revolutionary. Advancements and learning come mostly from needing to solve a problem. The space program (though certainly expensive) does provide unique challenges, and questions that we otherwise wouldn't ask.

Your statement seems to try to isolate things. I think pretty much everything is related. Consider how very different music and math are, yet studying one helps with the other.

Here's some nasa developed technologies

They're only operating in the UK so they bought http://www.gmail.co.uk/ instead (before google bought gmail.com). One of the biggest problems with the current DNS system is that if you register http://www.nasa.gov/ it doesn't stop someone else from buying http://www.nasa.net/, http://www.nasa.com/, http://www.nasa.org/, or whatever. Time to get rid of top level domains altogether.

Anybody who argues against manned space flight should take a long hard look at Comet Shoemaker-Levy 9(http://www2.jpl.nasa.gov/sl9/). This is a close as a sign, from God, as you will ever get to get the hell off this planet. Having all of humanity on one planet is asking to be wiped out. It was so convenient that this comet happened to hit Jupiter just when Earth happened to have a spacecraft in the area. Just so everybody understands; if even one of those chunks had hit the Earth life would be back to single cell state. We have a clear and present danger. Earth is in a shooting gallery and we need to get self-sufficient colonies elsewhere as fast as possible. To paraphrase Heinlein: "Humans always have and always will live on the edge of disaster."

As for China; I would say watch their plans for the moon. I think China has much bigger plans for the moon than most people realize.

Take a look at this picture. See the problem? Compariing the US to a densly populated and wealthy small country is not valid. It might be valid to compare NY to France. But revamping the US infrastructure to support this stuff and maintain backwards compatability takes time. Plus companies have to earn back their investment in the current infrastructure. I lived in Bahrain in theearlly 90's and they were one of the first countries with cheap handheld cellular. Revamping that country's infrastructure amounded to replacing a handful of towers. Imagine what it would take for the entire US. Still, I don't see why select US cities don't push to be on the bleedign edge of comms infrastructure expecially since it would likely lead to more hightech jobs.

Proper link here.

Here's a link to a better map on the MGS website.

http://mgs-mager.gsfc.nasa.gov/publications/pnas_1 02_42_connerney/

The one you linked was from the original data back in 1999.

Don't know if this is THE map, but it is a map of Mars Crustal Magnetic Field Remnants: http://photojournal.jpl.nasa.gov/catalog/PIA02819

Calculated every handful of minutes with cloud cover updated eight times a day, all thanks to the power of Xplanet. The daylight background map is now the Blue Marble monthly map. The current one is automatically rotated in place the first day of each month... Enjoy the realistic seasonal snow cover and the changing vegetation !

Two resolutions are available :

800x600 - http://www.ruwenzori.net/earth/earth800.html

1280x1024 - http://www.ruwenzori.net/earth/earth1280.html

I hadn't considered any interstellar slow-down, dark matter you mean?

The simple fix is to beam more energy at the craft.

I'm not a rocket scientist either, but I tend to think of GIANT spacecraft when you are trying to get going really fast using propellant, the solar sails would either have to be GIANT as well in order for it to be worth the effort.

When you talk about nuclear rockets you are talking kilotons, a solar sail powered interstellar spacecraft could be 1 or 2 tons.

If it's possible to use tethers to generate power:
(http://science.nasa.gov/newhome/headlines/ast15oc t98_1.htm/) ....it seems possible that the elevator cable could be harnessed to do the same. Either way you are swinging a cable through a magnetic field.

This "new" thruster sounds an awful lot like an Ion Engine. Not to discount this or anything. But theoretically, the ion engine can propel a craft to near the speed of light, it will just take it a few thousand years to get up to that speed. I think one engineer refered to it as "acceleration with patience." I guess I'll be more impressed when I see one of these things used in a vehicle launch situation.

The article seems to imply that the advatage of a Magnetohydrodynamic rocket is lower launch costs, but someone seems to be missing the fact that the chief advantage of an MHD engine is high exhaust velocity. This means higher thurst per kilogram of fuel expended, but also much reduced acceleration, far too little to take off from the Earth's surface, let alone get to orbit. Really, a perfect surface to orbit vehicle would have a specific impulse of arounf 1000 seconds (compared to the Shuttle's 452 sec)...

That's why NASA's own MHD program, VASMIR, is designed for in-space propulsion: http://www.nasa.gov/vision/space/travelinginspace/ future_propulsion.html

Simon ;)

Mareta West determined the landing site for Luna 9 (the first spacecraft ever to land on the Moon)? I doubt that. Perhaps what the author meant is "the first manned flight ever to land on the moon"?

FWIW I saw something about this a week or two ago on nasa tv (I think it was "realplay http://www.nasa.gov/ram/35037main_portal.ram" but maybe some other stream). The director was presenting the plan for shuttle replacement and personnel reduction. It sounded like they were going to try to use put personnel in other projects and not fire people. I also saw video animation of the upcoming shuttle replacement and it was extremely cool, including an apparent change in thinking to making less expensive but more useful modules based mainly on current shuttle technology, and which would be 10 times safer than shuttle.

I just opened that stream up again now and it is extremely awesome. I'm watching ISS and ground control. Woman (Bill MacArthur space communicator and friend/past mission participant Pam Melroy) in ground control talking to ISS says, "Or is it just the Diet Coke of evil?". Time now 12:11:46 am JST or 15:16:46 UTC. Watch it!

Knowing the damage one of those capsule would cause to a satellite, it's like allowing people to put their tombstones on the highway ...

Can someone relly tell me what actually works as intended at NASA

Yeah. Robots.

Ah, government. "If it's not broken, fix it until it is."

http://www.nasa.gov/pdf/107493main_FY_06_budget_su mm.pdf

Looking back to the 50's, in real dollars NASA's budget has been increasing pretty much throughout except for from 66-71 or so. I could really throw my karma to the wind and point out that the budget under Bush jr has increased consistently in both then and 1996-constant dollars, and that it appears Clinton and Nixon seem to be the only two presidents who presided over a continuous decrease in NASA budget (constant 1996 dollars).

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

Of course, the article is about cuts at JPL and I am talking about NASA's budget... but I feel perfectly comfortable with a slight redirect like that given that the majority of posts (and most space-related threads on slashdot) schitzophrenically vacillate between "we need more money for human space exploration" and "human exploration budget is raiding scientific space research".

I've built a page with 540 by 270-pixel copies of each month, some of the ancilliary data files, and links to the 8km/pixel and 2km/pixel files:

http://earthobservatory.nasa.gov/Newsroom/BlueMarb le/BlueMarble_monthlies.html

This one has been my desktop background since time immemorial. It's a 39.6MB TIF, play around with the settings to convert this really nicely, JPEGs floating around on the web don't look anywhere near as nice. http://visibleearth.nasa.gov/images/1438/land_ligh ts_16384.tif

Get the plugin for Nasa Worldwind http://worldwind.arc.nasa.gov/.

It was just released at WorldWind Central http://worldwindcentral.com/ today!
This is an application that will download the images as you want them, and you can fly around, zoom in from outer space and back out again - all kinds of stuff.

WorldWind is an open source program developed by NASA and the community.

Wow- that was FAST!
Looks like you guys beat Google Earth on another one!
This is really nice imagery-
Just in time for the upcoming WorldWind 1.3.3 http://worldwind.arc.nasa.gov/ release, eh?
Great work- you guys at http://www.worldwindcentral.com/ are amazing . . .

All right, Nowak at World Wind Central has mirrored and created an add-on for NASA's World Wind. You can now easily view the entire next generation blue marble sets on any windows machine.

Please consider donating so we can continue to provide quality services like this.

To use simply download the client and the add-on.

That's an image from the original Blue Marble.

http://earthobservatory.nasa.gov/Newsroom/BlueMarb le/BlueMarble_2002.html

The introductory paragraph says the movies are "a visualization of the dataset [] derived from imagery."

The introductory paragraph says the movies are "a visualization of the dataset [] derived from imagery."

That's a very valid criticism of the climate models of around 1985. Slab oceans are not used in state-of-the-art climate models.

modelers set up the model so that CO2 holds more heat in the model

Well, nature set things up that way too. It's been known since the 1890s.

do they just solve for two of the three (pressure and temperature, but not volume)

um, ever hear of an equation of state?

I can go on for hours about how completely inaccurate these models are.

You are very creative indeed. Unfortunately, you show no signs of knowing what computer models are in use, why, or how they relate to the science.

we have data that all of the inner planets are now heating up.

Where? The Mars matter is addressed here.

Trillions of dollars and Millions of lives will be lost if the "we should take action just in case" crowd wins.

I don't know why you are only interested in the risks on one side.

We have no hard evidence to support anthropogenic global warming theories.

Hope this helps

Done by the same group.

http://www.visibleearth.nasa.gov/view_rec.php?id=1 438