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The Earth Impact Effects Calculator lets you calculate the destructive effect of various asteroid impacts.

Judging by the results here, the blast wouldn't arrive at all if it hit in the middle of the ocean, as significant energies wouldn't travel beyond a few hundred kilometers. However, a tsunami would certainly be formed. While there are no stats given at that site for the size of such a tsunami, I doubt that it would reach more than a few miles inland, and there would be time to fly the major sections of government out of the area, if they weren't removed well before the impact anyway.

(Yes, I know the numbers at the site aren't exact, and there's some guesswork involved in impact angles and so on, but they're good enough for this discussion.)

I know it's a joke, but it got me thinking about collection techniques, and whether or not it would be best to simply only collect male samples.
Yes, in our politically correct minds, that sound sexist, but in reality, males have all the genetic information for both genders, they simply only have one copy of the X chromosome. But the statistical information from the male X chromosome should be highly correlated to the female population (every male got his X chromosome from a female, so the statistics in the populations should be highly correlated). But if you only study a male selection, you also have the option studying the Y chromosome ( Y chromosome phylogenetic map ) . And because the transmission of the Y chromosome is not governed by simple mendalian genetics, it provides an interesting method for phylogenetic reconstruction (much like mitochondrial DNA, which you only get from your mother). With female samples, you can only study the mitocondrial lines.

Is there any reason to believe that genetic statistics are vastly different between men a women? If they are not, would the study be more effective if it only concentrated on men?

(I'm not actually proposing to exclude women, I'm just asking questions)

What I want to know is, why not just pack a capsule into the shuttle's cargo bay? The cargo bay can hold a school bus, so they've got plenty of room to stick a Gemini capsule in there as backup, and still have room for satellites or whatever else they're hauling.

It will be a partial eclipse rather than a total one

Actually, I assume he did in fact mean the VLTI, or VLT Interferometer. Given the broken English, my first thought was that he was a European working on the project, but I'm too lazy to confirm that. The idea is basically to have a VLBI-like-array, only in the optical and IR, using the four VLT telescopes and a series of outrigger telescopes that can be moved around the main four. As to how it stacks up to Hubble in the visible, I'm not really an expert on that. But with baselines of order a hundred meters, the theory certainly looks good.

I have used the VLT in the infrared, and can tell you it (well, UT-4 with NACO) quite certainly does better than Hubble in resolution. And while my extragalactic friends (er, friends studying things outside the Milky Way, not actual alien friends) may not be happy to hear it, being able to image faint sources isn't the ultimate factor in ranking telescopes. I look for planets, so I care a lot about contrasts, and the VLT can very nicely out-perform Hubble there.

We've recently discovered n close, faint companion to the star AB Dor with the VLT-NACO system, and got some very good science out of it. This is an object Hubble looked for prior to us, and failed to detect. Mind you, we had some special optics that Hubble didn't, so we did have an advantage there.

But ultimately, I agree with your main point, that there are many factors in determining which telescope is best for your science. The VLT excels in areas where Hubble falters, and vice versa. Astronomy will be at its best with every resource it can get; there's a lot less redundancy than people assume. So yeah, boo NASA, and I need to figure out how to fit a "Save Hubble!" bumper sticker on my bike.

Snobol is the granddaddy of pattern matching languages. Yes -- it's an old language, and it has an unorthodox syntax -- but regular expressions are also old and have an unorthodox syntax.

There are several different implementations out there, the easiest to deal with is csnobol. http://www.snobol4.org/ has a bunch of information on the language.

The other language, Icon, was developed from research done on Snobol. Icon provides a more modern syntax and flow control. While not as powerful in pure pattern matching as Snobol, the whole lanauge can be used when string scanning. http://www.cs.arizona.edu/icon has a bunch of information on the language. There is an object oriented version of Icon that is being developed, unicon. http://www.unicon.org/ has information.

"However, it also contains significant quantities of aerosols and organic compounds (hydrocarbons), including methane and ethane."

"Interestingly, there are also trace amounts of at least a dozen other organic compounds (i.e. ethane, hydrogen cyanide, carbon dioxide) and water. The organics are formed as methane, which dominates in Titan's upper atmosphere, is destroyed by sunlight. The result is similar to the smog found over large cities, but much thicker. In many ways, this is similar to the conditions on Earth early in its history when life was first getting started. But it is this thick hazy atmosphere that makes it so hard to see Titan's surface."

I don't see how would it stagnate anything. On the contrary, we get two competing versions, where each can make its own design choices. Neither Gnome not KDE have full control of everything. If one of them doesn't want something, the other one might accept it.

And nowhere near as bad? Here on my laptop I have exactly one look: KDE. Very infrequently I use a lone Gnome app. That's very far from the mess I often see on Windows. Please try at least some of the following: Winamp, Sonique, AdAware, ZoneAlarm, any antivirus, Trillian, MSN, Norton Utilities.

Let's take a look at these programs:
Winamp
Sonique
AdAware
ZoneAlarm
Panda Antivirus
Trillian: Norton Utilities
MS Office 2003

Let's see... Winamp and Sonique are completely non-standard, and aren't even used the same way. AdAware has its own pretty widgets. ZoneAlarm has its own non-standard looking interface. Every antivirus I've seen at least paints lots of bitmaps everywhere. And even MS Office has menus that aren't found anywhere else.

Where's the consistency? Every Windows desktop I see these days is full of stuff like the above. And every Linux desktop I see is 99% KDE or 99% Gnome, with once in a while some lone app from the other environment.

While I get a kick out of most of these missions, I'm *really* waiting for the next Titan mission. I want to see a nuclear powered helicopter or cryogenic-temperature blimp (two proposals thusfar) patrolling around Titan; it'd be able to visit pretty much the entire moon. Huygens definitely was a "pose 5 new questions for every one it answered" mission. And if anything, Titan now looks even more like Primordial-Earth-In-Deep-Freeze than ever before. ::digs up one of his old posts to sci.space.tech::

There were some concept studies done of an "Aerover" blimp for Titan exploration a few years back. I suspect we'll soon seen those ideas thrown around again.

Post-Cassini Exploration of Titan: Science Rationale and Mission Concepts (compares helicopters, blimps, etc.)
Titan orbiter Aerover mission
http://www.jpl.nasa.gov/news/features.cfm?feature= 499
http://www.nasatech.com/Briefs/Mar03/NPO20609.html
http://www.space.com/scienceastronomy/solarsystem/ titan_blimp_020212.html

Here is NASAs budget. Try reading it sometime.

From the budget:

• 5.5 Billion is dedicated to Science including the James Webb Telescope, Keck Interferometer, Large Binocular Telescope Interferometer, , Terrestrial Planet Finder, Stratospheric Observatory For Infrared Astronomy (SOFIA), Gamma-ray Large Area Space Telescope (GLAST), SWIFT, Widefield Infrared Survey Explorer, Gravity Probe-B, RXTE, FUSE, Chandra, XMM, HETE-2, WMAP, INTEGRAL, CHIPS, GALEX, Spitzer, Astro-E2, LISA, Constellation-X, STEREO, SOLAR-B and many more but I am getting bored looking this stuff up for you.
• 2.7 Billion for Exploration Systems including CEV and Prometheus
• 906 Million for traditional aeronautics
• The remaining 6.7 Billion is to support the ISS, Shuttle and infrastructure.

• <sarcasm>But yeah, you are right... Bush threw everything at Pie-in-the sky stuff...</sarcasm>

found a forum on the DISR site. Why dont you post the question there?

found a forum on the DISR site. Why dont you post the question there?

You could always send him to the SALT Center. We have an array of assitive technology, including Kurzweil 3000, Inspiration and others. As for math, that seems to be worked through with tutors and other aspects of the program.

Hope that helps....

asbestos reform and asbestos related litigation is on fire

is this a joke? Given the origins of Asbestos..;

http://fp.arizona.edu/riskmgmt/asbestos_fire.htm

While it's still controversial and in an early stage of development, Mathematician/cosmologist Roger Penrose has presented some intriguing hypotheses that consciousness (and thus memory) may be quantum phenomena. His viewpoint is pretty well carried out by the Center for Consciousness Studies at the University of Arizona.

I'd like to see better dating. If the dates coincided within a few hundred or maybe even a thousand years, I'd be convinced. Best I've seen so far is hundreds of thousands of years, which is way too much - but then we're well within dating error bars at 250 myo.

Even without the "focused shockwave" theory it's certainly possible that a large impact could have triggered eruptions elsewhere. It would almost certainly be much more powerful - and more localized - than the tsunami earthshift was.

Another interesting idea that I've read is that the Earth experienced an increased influx of impacts at the time (for whtever reason) and there were impacts all over the globe. It'd be interesting if we discovered another large crater formation dating about the same time...

Something to ponder...

Impact Calculator gives 1.17*10^7 megatons if I input something similar to Chixilcub, while estimates I've seen on the recent tsunami quake aren't anywhere near in agreement but orders of magnitude smaller - which gives us a scale anyway. :)

SB

See also the Large Binocular Telescope . This page has some convincing photos showing exactly how "obsolete" Hubble has become. However, Hubble does have some advantages, and it's really too bad we're going to lose it, solely as a result of the recent Shuttle tragedy.

Link to LBT page: http://medusa.as.arizona.edu/lbto/whybuild/grbsspc .html LBT

Link to LBT page: http://medusa.as.arizona.edu/lbto/whybuild/grbsspc .html LBT

University of Arizona is building the Large Binocular Telescope [http://medusa.as.arizona.edu/lbtwww/], with with a pair of mirrors each 8.4 meters (25 feet) in diameter. The light gathering power and sharpness are both supposed to put Hubble to shame [ see http://www.nd.edu/~science/core/binocular/lbt_othe rtelescopes.shtml] using adaptive optics to remove the atmospheric blurring. It's a lot cheaper than Hubble, and while being ground-based has limitations, having it on the ground will make it much easier to repair and upgrade.

It's certainly not the first time Vulcanism* has been implicated in a mass extinction - the Deccan Traps, for instance, have been implicated in the KT event that is thought to have wiped out the dinosaurs 65 Million Years ago. There's even a school of thought that says the Chicxulub event may have triggered a major convulsion in the Traps - double jeopardy, if you will.

Except that the earth is only about 4000 years old and fossils were put there to test our faith, right?

* I nearly typed 'vulvanism', but that's a different story.

See, for example, these field test photos of the camera in the Arizona area. as they say:

To construct any of these projections, the direction of every pixel in each of the three imagers was measured and expressed as a nadir and azimuth angle in a spherical coordinate system centered on the imager in question. Parallax due to coordinate center offsets was ignored. The distortion due to the optical systems was removed using an empirically-derived unwarping function. The images were projected onto a mosaicking plane using one of several projection algorithms (mercator, conic, stereographic or gnomonic) defined below, causing the various images to be spliced together.)

oooooooo.... Pictures.

See, for example, these field test photos of the camera in the Arizona area. as they say:

To construct any of these projections, the direction of every pixel in each of the three imagers was measured and expressed as a nadir and azimuth angle in a spherical coordinate system centered on the imager in question. Parallax due to coordinate center offsets was ignored. The distortion due to the optical systems was removed using an empirically-derived unwarping function. The images were projected onto a mosaicking plane using one of several projection algorithms (mercator, conic, stereographic or gnomonic) defined below, causing the various images to be spliced together.)

oooooooo.... Pictures.

Gosh, sir, how do you explain my 760 in math on the SATs? (Sorry. I did get a 780 verbal, so maybe I am feminine after all.)

Was I exposed to too much testosterone in my mother's womb? Does this explain why I was a perfect milch cow for my children?

Or is my niece, who's in 10th grade, and has finished honors level Diff Eq at the local university, totally unfeminine?

The theories I believe he's quoting don't have much biochemical or brain-based research to back them up.

Their logo http://phoenix.lpl.arizona.edu/images/phoenix_logo _small.jpg remembers me firefox logo!

Does anyone know why the "o" in the Phoenix logo is the symbol for male? Also, what does the year 2007 have to do with anything?

Thanks. I also have just found a great page about the probe instrument: DISR.

Raw images (plenty of them)

Not unlike Mars...

More here!

Not unlike Mars...

More here!

Go here for a lot of Raw pics. There are at least 500 images here, I'd say. A lot of the images are very similar, and a lot are not very pretty to the eyes (hazy and blurry). I did notice some slight differences between the "at first glance identical" pics as I went through them in a slideshow viewer. http://www.lpl.arizona.edu/~kholso/jpeg/

Some images are now available here!

Here is a page with the examples of the image output.

http://www.lpl.arizona.edu/~kholso/test_images.htm

Pretty neat.

The images will be posted from the moment they are available at

http://www.lpl.arizona.edu/%7Ekholso/data.htm

The Huygens probe's landing site will be near 10.9 S, 169 E (191 W). (There is uncertainty as to the exact landing site since atmospheric winds that could blow the probe around are not well known.) This is on the side of Titan facing away from Saturn, so there will be no poetic images (or any other kind of image) taken of Saturn by Huygens.

Click here for information about the cameras.

What I don't get is why Slashdot is treating this as new news; they were first noticed by Cassini in pictures taken between October 15-20, 2004, and had been detected previously by Voyager. They've been widely reported in the past reporting about the Cassini mission (for example, here on Dec. 8th)

Slashdot: Yesterday's News, Today!

Well, according to the SEDS Entry on the Ring Nebula, recent research has confirmed that it is in fact toroidal, rather than spherical, in shape.

(or primary dimension)
No matter, no space, no energy, not even time exists beyond or without Consciousness.
If collection of matter can clump together and call itself You or I.
Then the mind and body and objects within one's grasp are mere tools of one's Consciousness.
'Life' (not always as we know it) exists wherever it is possible to exist, and is a product of Consciousness.

Some other online papers on consciousness:
http://jamaica.u.arizona.edu/~chalmers/online.html

I think ultimately the question is whether there is a single continuous "initial mass function" of isolated objects or not. The best idea as to how stars acquire their initial mass is that turbulence in the interstellar medium, which exists on all scales, establishes a power-law distribution of initial masses. Every once in a while, you get a very strong shock which passes by inside a giant molecular cloud and forces the collapse of a large region which then goes on to form a massive star. But more typically, you form stars more like our sun. And just as rare as massive collapses are very small mass ones which go on to form isolated brown dwarfs and free-floating planets. If this model holds up to be true, then we are all mincing words in our definitions of isolated systems, since they are all manifestations of the same universal formation process.

However, to avoid the difficult question of formation mechanisms, an IAU working group of some of the most respected people in the field established a working definition [ciw.edu] to define by fiat what it means to be a brown dwarf, and a planet. Extrasolar "planets" are those objects orbiting a star which are beneath the deteurium-burning limit -- regardless of how they are formed. "Brown dwarfs" are defined to be those which burn deuterium but not lithium, and "sub-brown dwarfs" (NOT free-floating planets!) are defined to be those isolated objects which do not burn deuterium. Even the working group itself admitted that this definition was not satisfying to a single member of the group, and so it is likely it will be replaced at a later time with something more physically-motivated. The "planet/planetismal/KBO" distinction was pushed back to our own solar system, since it will be some time before anyone sees anything that small in another system.

Also of interest is the following link, which gives a history of previous claims for additional planetary members of our solar system : SEDS [arizona.edu].

bh

The amount of energy released will depend on the velocity and angle of impact. You can do the math on the catastrophe calculator.

"The latest update from NASA now gives 2004 MN4 a [increased/decreased probability of impact]. Somebody tell Bruce Willis!!! NASA advises, however, that this probability is likely to decrease in the near future. There is also a 50% chance that it will increase. You can calculate the impact outcome based on some parameters. Guys, this only gives us til April 13, 2029 to have sex... Friday the 13th!

According to this calculator the crater would be about 9 kilometers in diameter, it would cause a 7.1 strong earthquake and a 44 m/s shockwave a hundred kilometers from the epicentre. (Assuming 90 degree collision angle and iron composition - basically, the worst.)

Note that this assumes 4940 megatons in kinetic energy, and Nasa says it's "only" 1600.

Guestimating volume if it's a sphere is (4 / 3) * pi * (((0.390/2) km)^3) = 31 059 355.8 m^3 (calc)

Guestimating density if it's a sphere is (7.9e+10 kg) / ((4 / 3) * pi * (((0.390/2) km)^3)) ~= 2540 kg / m^3 (calc), which is necessary for the calculator, and looks like a reasonable figure.

Totally guessing impact angle of 45 degrees.

I'm sure they actually have a decent fix on what part of the Earth it would hit. And a pretty decent guess of the angle of impact, too.

The low impact velocity means no fireball, apparently, and very little immediate effect once you get a few hundred miles away. It looks like this calculator doesn't mention the potential for tidal waves, though. Dunno what about that. And dunno if it's ignoring potential climate effects.

First of all, you will be wanting to throw a 390 meter diameter rock at the earth. As for the asteroid simulator pages there are several:
Arizona Site - I prefer this one for its data.
UMD Site - I like the nifty pictures.

I would also like to point out that this asteroid has decreased in size from 440 meters in diameter to 390 meters in diameter. So let's hope that as the probability goes up, that size will go down. Similarly, the energy has dropped to 1,500 megatons of TNT (after atmospheric losses). Also, the atmosphere will cause it to break up (starting at 50 km up) into smaller fragments that will shower a 1.25 km by 0.88 km area. This is not significantly dispersed to prevent a crater from forming so expect a 5 km diameter crater (0.5 km deep) followed by a 6.7 magnitude seismic result. Don't expect much ejecta 100 km away or more and don't expect too much of an air blast/noise. Don't worry too much, something this big hits earth every 35,000 years on average.

It'll be interesting to see if insurance companies keep the phrase "objects falling from sky" in the list of insured accidents.

• Impact Energy: 1.23 x 10^19 Joules
• Crater Formed in Seafloor: 2.46 km diameter
• Earthquake: 6.0 on Richter Scale
• Radiant Flux at 100 km: 7.68 times that of sun

It's not the same rock. This one is 800 meters across, not 5.

Blatant karma whoring: impact simulator link.

I think ultimately the question is whether there is a single continuous "initial mass function" of isolated objects or not. The best idea as to how stars acquire their initial mass is that turbulence in the interstellar medium, which exists on all scales, establishes a power-law distribution of initial masses. Every once in a while, you get a very strong shock which passes by inside a giant molecular cloud and forces the collapse of a large region which then goes on to form a massive star. But more typically, you form stars more like our sun. And just as rare as massive collapses are very small mass ones which go on to form isolated brown dwarfs and free-floating planets. If this model holds up to be true, then we are all mincing words in our definitions of isolated systems, since they are all manifestations of the same universal formation process.

However, to avoid the difficult question of formation mechanisms, an IAU working group of some of the most respected people in the field established a working definition [ciw.edu] to define by fiat what it means to be a brown dwarf, and a planet. Extrasolar "planets" are those objects orbiting a star which are beneath the deteurium-burning limit -- regardless of how they are formed. "Brown dwarfs" are defined to be those which burn deuterium but not lithium, and "sub-brown dwarfs" (NOT free-floating planets!) are defined to be those isolated objects which do not burn deuterium. Even the working group itself admitted that this definition was not satisfying to a single member of the group, and so it is likely it will be replaced at a later time with something more physically-motivated. The "planet/planetismal/KBO" distinction was pushed back to our own solar system, since it will be some time before anyone sees anything that small in another system.

Also of interest is the following link, which gives a history of previous claims for additional planetary members of our solar system : SEDS [arizona.edu].

lzx

Out in the Kuiper belt and the Oort cloud [arizona.edu] there are thought to be as many as one trillion objects - most small 1 to 10 km chucks of ice.

The really interesting question is, what is the mass distribution ? (I.e., how does the number of objects scale with their mass ?) This is basically unconstrained by real data. All such cosmic mass distributions are steep, but many (for example, planets in the Solar System, Asteroids in the Asteroid belt) are dominated by the most massive bodies.

If this holds true in the Oort cloud, in particular, there could be some pretty big objects. Even a Jupiter sized object might be able to hide from the Infrared surveys (the best way of detecting such an object). imd

I think ultimately the question is whether there is a single continuous "initial mass function" of isolated objects or not. The best idea as to how stars acquire their initial mass is that turbulence in the interstellar medium, which exists on all scales, establishes a power-law distribution of initial masses. Every once in a while, you get a very strong shock which passes by inside a giant molecular cloud and forces the collapse of a large region which then goes on to form a massive star. But more typically, you form stars more like our sun. And just as rare as massive collapses are very small mass ones which go on to form isolated brown dwarfs and free-floating planets. If this model holds up to be true, then we are all mincing words in our definitions of isolated systems, since they are all manifestations of the same universal formation process.

However, to avoid the difficult question of formation mechanisms, an IAU working group of some of the most respected people in the field established a working definition [ciw.edu] to define by fiat what it means to be a brown dwarf, and a planet. Extrasolar "planets" are those objects orbiting a star which are beneath the deteurium-burning limit -- regardless of how they are formed. "Brown dwarfs" are defined to be those which burn deuterium but not lithium, and "sub-brown dwarfs" (NOT free-floating planets!) are defined to be those isolated objects which do not burn deuterium. Even the working group itself admitted that this definition was not satisfying to a single member of the group, and so it is likely it will be replaced at a later time with something more physically-motivated. The "planet/planetismal/KBO" distinction was pushed back to our own solar system, since it will be some time before anyone sees anything that small in another system.

Also of interest is the following link, which gives a history of previous claims for additional planetary members of our solar system : SEDS [arizona.edu].

fu