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Stardust Probe Enters Comet's Tail Tomorrow
Tortured Potato writes "NASA's Stardust probe is about to pass through the tail of Comet Wild 2 at 11:40am PST, January 2nd. If all goes well, the probe will return the material to earth for research in 2006-- the first extraterrestrial material captured from outside the moon's orbit."
Why does this sound like the beginning to a bad sci fi movie:
activestudios web design
It will allows us to better study the properties of intersolar and pansolar materials in high-velocity space bodies. We'll be able to gain insights into the likely composition of planets which are too far away to analyse directly, and if this works we can confirm whether or not it is actually a 'vapor' trail or some other substance. There are other, lesser implications for space travel also, but that's about the gist of it.
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Didn't the scientists see Armageddon?!? Rocks in space are far too unpredictable!
The Unfolding Project
Hope the probe doesn't plan any side trips to Mars given how hungry the Martians have been lately...
dust grains will fly by the spacecraft at about 13,000 mph, or six times faster than a speeding bullet.
-calyxa
Decay! Decay! Decay! -Helium
Stardust Probe Enters Comet's Tail Tomorrow
*waka-chicka-bocka-chicka-wowawow-wow*...
I'm so very sorry. D'oh.
I want to drag this out as long as possible. Bring me my protractor.
It's a silicon-based solid with a porous, sponge-like structure in which 99.8 percent of the volume is empty space. By comparison, aerogel is 1,000 times less dense than glass.
The above line, and more, are available here
And yeah, I'd like to play around with some of this stuff as well. The picture of someone holding a 'brick' of it looks like a bad Photoshop job.
I've seen real some aerogel (aerofoam) before. It's difficult to describe, it looks like a solid cloud of gas. It's very fragile, so it probably wouldn't be very useful to build vehicles out of. The best use of aerofoam is as an insulator.
Is it possible to trap helium inside of aerogel? If so, you could have a lighter than air solid. That would be very cool.
This could be very interesting in that there are rumblings that the "tail" of a comet may not actually be melting ice, etc (the dirty snowball model that is the current accepted theory). James McCanney has an interesting theory called the Plasma Discharge Comet Model.
From the website http://www.usinternet.com/users/jmccanney/
"The work showed among other things that comets were not dirty snow balls sublimating (vaporizing) in the solar environment, but were a complex plasma discharge interaction involving an asteroidal comet nucleus with the "solar capacitor", the capacitor being the result of a differential flow in the solar wind of high energy particles leaving the sun. The balance of charge in the solar system and a myriad of of other previously unknown effects were predicted by the theory, including the existence of an electron sheet arriving from the sun at a cometary nucleus and resulting x-rays. Only recently have these been verified by observation. The new comet theory also explained that the tail matter was not moving away from the comet nucleus, but was being drawn in by electrical forces millions of times more powerful than gravity or solar wind forces alone. Essentially a comet was now seen as a huge "cosmic vacuum cleaner". Comets were being captured into the solar system by the existing planets and the comet "tail drag" helped to circularize their orbits. Many commonly stated beliefs regarding the nature of the solar system were being dispelled with more subtle explanations. "
The implications of this theory are intriguing as it may explain how Mars lost its atmosphere as well as such bizarre things as the LaBrea tar pits and all of the trapped creatures in it. (Under this theory a larger body can pull elements from a smaller body if it gets close enough such that things such as oil may not be decomposed dinosaurs, but instead gets "rained" down when a smaller planetary body moves close enough).
Interesting stuff.
The significant problems we face cannot be solved by the same level of thinking that created them. -Albert Einstein
I was on a NASA committee involved in the predesign stages of the Stardust probe (we weren't designing it ourselves, rather we were consulting with one of the teams at the JPL who were) and this comet dust was one of our main points of focus. You'd think of dust as about the most innocuous stuff there is, but it was quite a challenge designing all the intricate mechanisms on the craft to be resistant to it - at the speed it travels, it can be like sandpaper on all the components.
why spend billions on pursuing goals that don't do anybody a lot of real good, when we could spend it on helping humanity
Because hope is more valuable than the billions, and helps humanity immensely.
Business isn't willing to pay for products, innovation and careers, so we get brands, mortgage commercials and layoffs.
While I don't completely agree with the parent, I do disagree with you. We can spend money constantly trying to inject money into it, but in the end it won't help anything. You get a temporary gain, but at the end of the day you will always have the poor and the uneducated and the underprivileged. It's unfortunate, but it's true. Space programs are kinda a high risk gamble, for relatively little cost. It's like buying a lottery ticket, you know the odds are against you, but you don't miss the $1 anyway, and you got a chance. Space exploration has the chance of forever changing the human condition for the better. As long as we sit on the earth we will slowly burn through it's natural resources whatever we do. The space program is a tiny speck in the federal budget, and most of the cost overruns have been caused by petty politics, not the program itself. A quick glance at google showed me the NASA budget is around 15 billion. The Federal budget is around 2-3 trillion dollars. What great change will another 15 billion do? A small increase in another federal system, and we lose a symbol of our nation, a motivation for technological improvement ( Virtually every product you use, somewhere along the line, was impacted by technology developed for or because of the space program), and hope for a better tommorow. You can throw dirt into a fast moving river forever, and never have it fill up, or start building a bridge. The real probelm with NASA is they have to constantly fight to get their meager budget and are at the mercy of the whims of congress. The politicians need to do their job and give NASA a goal, like Kennedy did, and but out. A smart man knows the areas that arent his strengths, and most politicians couldn't tell a space shuttle from a episode of star trek.
Aerogel is sort of a silicon foam, originally developed on the shuttle, IIRC its the least dense/lightest solid material. Its also nearly transparent if formed right, and is used as an insulation between window panes and i think i heard about a jacket or vest using the material.
"Sic Semper Tyrannosaurus Rex."
This has never been done before. Any time we wander into the unknown, we are likely to be surprised and learn something unexpected. Historically, this has proven to be very productive.
In this case specifically, it's interesting because we're collecting information and material from a new type of solar system object, one of very few that are within easy reach. There are theories based on indirect observations which suggest what will be found. Comparing what is found to what was predicted will help to test and refine (or invalidate) those theories.
There are good reasons to believe that comets are leftover raw material from the formation of our solar system, objects which did not get gobbled up by larger objects and have spent most of their time since those early days orbiting out beyond Pluto's orbit. Then some chance encounter in the frigid boondocks of the outer solar system bent their orbit in toward the inner solar system.
So, the Stardust probe is hopefully collecting a sample of pre-solar system material that's been in deep freeze storage for 4 or 5 billion years. That material is believed to be composed at least partly of fragments blown off from stellar explosions even farther back in time. It is literally star dust. This is an opportunity to get our hands on material that may be the same stuff that the Hubble and other telescopes look at from across light-years of space, all without leaving the neighborhood.
No one knows what we'll find, but it's bound to be interesting, adding another piece to our understanding of the universe.
``The World Health Organization (WHO) and other UN bodies estimate the cost of providing treatment and prevention services in developing countries for tuberculosis, HIV/AIDS and malaria at $12 billion a year '' (The Black Vault).
I happen to agree with you, that we could cut other, far more expensive programs and do a lot more good. Cut corporate welfare, cut fat contracts to Halliburton (who has previously been convicted of embezzling millions in government funds), cut spending on weapons the military say they don't need simply because it gives money to some senator's constituents.
Hell, if we took the billions spent on ousting Saddam and spent them on providing humanitarian aid around the world (see how far it could go), I don't think there would be very many terrorists still out to get us, and I doubt they'd have nearly as much support.
So yeah. I think you're right about priorities. But saying we could cut other programs instead doesn't mean a thing. That money could be doing far more good--in terms of concrete improvements like health care and food as well as abstracts like literacy and education--than it does now.
And despite it all, I do like the space program.
Those comets still on the prowl are essentially icy time capsules: calling cards of the solar system (and the galaxy's) early history. Having a look at a comet's raw materials will shed some interesting light on how we all got here.
Of course, if the theory that the solar system was built by comets is correct, you needn't look much further than your skin for a sample of ancient interstellar material.
This is my post. There are many others like it. If you don't like what you read here, go try one of the others.
Ummm, nah. Even I'm not going to touch that one.
KFG
What if a probe were sent to a comet to crash into it in such a way that was redirected towards (but not quite directly at) the Earth? The comet might then enter orbit around the Earth and be retrieved with or studied from the space shuttle?
Unknown host pong.
December 31, 2003: Philosophers have long sought to "see a world in a grain of sand," as William Blake famously put it. Now scientists are attempting to see the solar system in a grain of dust--comet dust, that is.
If successful, NASA's Stardust probe will be the first ever to carry matter from a comet back to Earth for examination by scientists. It would also be the first time that any material has been deliberately returned to Earth from deep space.
And one wouldn't merely wax poetic to say that in those tiny grains of comet dust, one could find clues to the origin of our world and perhaps to the beginning of life itself.
Comets are like frozen time capsules from the time when our solar system formed. Drifting in the cold outer solar system for billions of years, these asteroid-sized "dirty snowballs" have undergone little change relative to the more dynamic planets. Looking at comets is a bit like studying the bowl of leftover batter to understand how a wedding cake came to be.
Indeed, evidence suggests that comets may have played a role in the emergence of life on our planet. The steady bombardment of the young Earth by icy comets over millions of years brought some of the water that makes our brown planet blue. And comets contain complex carbon compounds that might be the building blocks for life.
Launched in 1999, Stardust will rendezvous with comet Wild 2 (pronounced "Vilt" after its Swiss discoverer) on January 2, 2004. A rendezvous with a comet is a little like a rendezvous with a Gatling gun on a foggy night. As Stardust plunges through the hazy clouds of gas surrounding Wild 2's core, dust grains will fly by the spacecraft at about 13,000 mph, or six times faster than a speeding bullet. The "eyes" of Stardust, an onboard camera, will peek out from the body of the craft through a periscope to avoid damage. A Whipple Shield--a stack of five sheets of carbon filament and ceramic cloths each spaced 2 inches apart--protects the rest of the spacecraft.
Stardust will use a material called aerogel to capture some of the fast-moving grains. Aerogel is a foam-like solid so tenuous that it's hardly even there: 99 percent of its volume is just air. The ethereal lightness of aerogel minimizes damage to the grains as they're caught. Mission planners hope to catch more than one thousand grains larger than 15 microns in the aerogel.
Wild 2 orbited the sun beyond Jupiter until 1974, when it was nudged by Jupiter's gravity into a Sun-approaching orbit--within reach of probes from Earth. Since then the comet has passed by the Sun only five times, so its ice and dust ought to be little altered by solar heating. Pristine dust from Wild 2 can tell us what the solar system was like before it was baked by 4.5 billion years of sunshine and radiation.
After the encounter, Stardust will loop around the Sun on a two-year journey back to Earth. In January 2006, home again, the spacecraft will eject the Sample Return Capsule (SRC), which looks like a miniature Apollo capsule. The SRC will parachute to Earth and, if all goes as planned, land in Utah where scientists will be waiting...
To see a world in a grain of sand
And a heaven in a wild flower
Hold infinity in the palm of your hand
And eternity in an hour
William Blake (from Auguries of Innocence, c.1800)
- Kaos games and encryption systems developer
There's a site that JPL maintains with information, but it's been tough for me to maintain a link to it because they keep reorganizing their file directories. As of the current nano-second, more information is available via the Stardust FAQ.
Also, if anyone would like to get their own name onto one of the next missions (or see if you're already included), here's where you can enter/search for your name aboard the Deep Impact probe, which is heading out to meet with a comet in 2005. Keep in mind though that January 2004 is the deadline for entering new names. For more info, check here for the Deep Impact fact sheet.
Elonka :)
Back in 2000 I trained a group of engineers/science type folks at JPL in Pasadena. One of the members of that class was part of the smaple return program that has the goal of returning samples from Mars, several comets, and a some asteroids as well. Stardust is just one of many projects along these lines. Stardust had been launched before I taught the class but one of my co-workers had taught the Stardust group.
The crumple shield concept wouldn't work at the velocitys involved for most of the targets but odds are they considered it, just look at the airbags used for Pathfinder and Beagle2. It could still work for smaller asteroids though.
As to all the talk about pathogens being returned to Earth by these probes, ala "Andromeda Strain", I did ask. There is an department whose ONLY job is to work out how ANY cross contamination can be prevented, they don't want to put terestrial pathogens onto other worlds either.
I still worry about it a little but not as much as I did after that visit.
She can suck the life out of me any day!
Soylent Green is peoplicious!