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Consider: Even if you make it up to LEO for free, you have to get to the item and match your position and velocity in the direction the space salvage is traveling to a degree where you (or your robot, whatever) can grab it. Of course you have to abide by the ideal rocket equation http://exploration.grc.nasa.gov/education/rocket/r ktpow.html. Great. You got your first piece. Now you have to change heading and velocity to intercept piece #2. These vectors aren't all heading in the same direction at the same location. And they are only tracking about 13,000 pieces in NEO ... that's not very many pieces given the vast area of space there is! Consider 13,000 random objects on the surface of the earth, now extend it upwards a hundred meters, and add a volume of 1000m in the vertical direction. Long story short, you can't turn a profit given the fact that you need fuel to power the robot to collect this stuff. And given the fact that commercial ventures are starting to break the price point barrier - check out spaceX - 10k a kg will drop an order of magnitude in the next 10 years, easy.

Don't forget you have to be careful to dodge the amount of space trash out there when looking for new pieces. Probably costs a decent amount of time and money to maneuver around that garbage. Someone should really do something about it. :\

Certainly, some types of space salvage (derelict rockets, satellite fragments, etc.) will have a higher value than others (paint flecks, rocket slag, etc.), but even the lowliest dist speck will have value, for the simple reason that it is there.

I understand the argument from the standpont that it cost money to put the salvage into orbit. However "collecting" may wind up costing you more than the fragment itself weighs. Consider: Even if you make it up to LEO for free, you have to get to the item and match your position and velocity in the direction the space salvage is traveling to a degree where you (or your robot, whatever) can grab it. Of course you have to abide by the ideal rocket equation http://exploration.grc.nasa.gov/education/rocket/r ktpow.html. Great. You got your first piece. Now you have to change heading and velocity to intercept piece #2. These vectors aren't all heading in the same direction at the same location. And they are only tracking about 13,000 pieces in NEO ... that's not very many pieces given the vast area of space there is! Consider 13,000 random objects on the surface of the earth, now extend it upwards a hundred meters, and add a volume of 1000m in the vertical direction. Long story short, you can't turn a profit given the fact that you need fuel to power the robot to collect this stuff. And given the fact that commercial ventures are starting to break the price point barrier - check out spaceX - 10k a kg will drop an order of magnitude in the next 10 years, easy.

Java based orbit tracker courtesy of NASA:

http://science.nasa.gov/Realtime/JTrack/3D/JTrack3 D.html

Space.com has a breakdown of responsibility by country of some of the larger debris in space.

And if you're really hardcore into space debris (it's hard to even type that without laughing), Orbital Debris Quarterly News is your magazine!

I guess I could just call someone.

Call the guys at JPL, they are secretly working on a Warp Drive, just don't tell anyone.

Short answer: No.

Long answer: Mach is simply a multiple of the speed of sound. As a result it changes with altitude and atmospheric conditions. NASA has a nice calculator for divining the approximate value for Mach at a given altitude.

Another technology called Space Time Block Coding (STBC) will reduce signal dropout by using multiple antennas for redundancy.

I knew all those years of Star Trek would eventually lead to every day applications.
Now we can use our wireless routers for subspace communication with strange new worlds and new life forms, and boldly route where no one has routed before.

LEO's hardly a vaccuum.

I thought about mentionting that it's a near vaccuum, but I figured it was pretty much irrelevant to my point. The Space Shuttle orbits with an approximate velocity of 17,321 mph. (Relative the the Earth, of course.) For that to be Mach 25, the Space Shuttle's altitude would have to be about 25,000 feet! Yet the Shuttle orbits at an altitude of over 100 miles (>528,000 feet). The highest my calculator goes is 250,000 feet. At that altitude, the speed of sound is only 602 mph, making the Shuttle's velocity Mach 28. Now I'm far too lazy to whip out the mathematical models to determine how fast sound travels at 100 miles and up, but it's a guarantee that it's far, far lower than the 692ish mph that's used to calculate Mach 25.

Or in other words, using Mach to determine the Shuttle's velocity (rather than engineering design) is nonsensicle. :-)

LEO's hardly a vaccuum.

I thought about mentionting that it's a near vaccuum, but I figured it was pretty much irrelevant to my point. The Space Shuttle orbits with an approximate velocity of 17,321 mph. (Relative the the Earth, of course.) For that to be Mach 25, the Space Shuttle's altitude would have to be about 25,000 feet! Yet the Shuttle orbits at an altitude of over 100 miles (>528,000 feet). The highest my calculator goes is 250,000 feet. At that altitude, the speed of sound is only 602 mph, making the Shuttle's velocity Mach 28. Now I'm far too lazy to whip out the mathematical models to determine how fast sound travels at 100 miles and up, but it's a guarantee that it's far, far lower than the 692ish mph that's used to calculate Mach 25.

Or in other words, using Mach to determine the Shuttle's velocity (rather than engineering design) is nonsensicle. :-)

The slingshot technique works because Jupiter is also moving--it's in orbit around the Sun, at about 30,000 mph (48,000 km/hr). When the probe approaches Jupiter from behind, the probe is gravitationally attracted to something (Jupiter) traveling at 30,000 mph, so it speeds up. Relative to Jupiter, you're right, it's a zero-sum game (i.e., the probe does seem to speed up and then slow down again, relative to the planet) but the velocity of concern is the so-called heliocentric velocity, or the velocity relative to the Sun, and that is greatly increased.

Note that there is conservation of energy, of course; Jupiter also slows down in its orbit slightly in response to the energy it adds to the probe, but the amount is unmeasurable due to the mass ratio between Jupiter and the probe. The speedup is therefore considered "free."

Google is your friend; see this page, this page, this page for more information.

Regarding your second question, the probe doesn't slow down again, and does do a very fast flyby. However, we know so close to nothing about Pluto that we don't have to get very close to get new information--for example, the resolution of the New Horizons cameras will exceed that of the best Earth telescopes (including Hubble) for 150 days. (Of course, it will take 4-9 months, depending on which estimate you like, to transmit the data back to the earth at the probe's minimum data rate--which it likely will use at that distance--of 800 bits/s.)

One wonders if NH might contribute some data to finally solve the Pioneer anomaly.

The Pioneer probes are spin stabilized and therefore require only minimal use of thrusters to keep their antenna pointed to earth. The Voyager probes were three axis stabilized, requiring rather frequent use of the thrusters to keep it pointing in the right direction, which made it essentially impossible to measure the Pioneer anomaly. New Horizons can operate in both modes, so it will most probably be spin stabilized during most of its trip from Jupiter to Pluto, and may therefore provide more evidence for or against the Pioneer anomaly.

In many ways it's a pity this is not a Uranus Probe - the headlines would have been fantastic. However we've been there with Voyager 2, so that'll probably have to wait until somone finds a way of mining the helium 3 [PDF] in Uranus's atmosphere.

Seriously though: this mission is great stuff, this pixelized ball is the best picture we've got of Pluto, and it would have been a shame if we couldn't spare a few million dollars to improve it, and get some data on the Kuiper Belt at the same time.

To enter orbit around a planet you need to be going slowly when you get there, at no more than the orbital speed for the planet. New Horizons will be going at 11 km/s when it flashes by Pluto, snapping pictures like mad, whereas the orbital velocity for Pluto is just over 3 km/s. NH is moving at least 3 times too fast to go into orbit.

If you wanted to go into orbit, you'd have two choices. The first, and most economical, is to launch the spacecraft on an elliptical trajectory that just barely reaches out to Pluto. That gets the spacecraft there with the lowest possible speed relative to Pluto. You still have some braking to do, but it's the least possible. Problem is, the length of such a trajectory is about half the period of Pluto's orbit, i.e. 125 years. Ugh.

If you speed things up by taking a faster trajectory, then you end up with much more braking to do. Then the problem becomes: how do you lose all that speed? If the planet had an atmosphere, and you have good heat shielding, you can do a little aerobraking, which is what's done with Mars. But with an airless world you're stuck with bringing along enough fuel to do almost as much braking as you did accelerating from Earth orbit. So far, that has been very difficult without a very large spacecraft. One plausible hope for improvement is to bring along a real nuclear reactor (instead of just an RTG) which can provide lots of electric power, and then use a high-efficiency ion drive to slow yourself down.

Funny you should ask this. Sagan said it in Cosmos, I just read that portion last night. From a quick Google search:
http://math.ucr.edu/home/baez/physics/ParticleAndN uclear/photon_mass.html
http://imagine.gsfc.nasa.gov/docs/ask_astro/answer s/960731.html
http://www.physlink.com/Education/AskExperts/ae180 .cfm
http://www.usatoday.com/weather/resources/basics/w onderquest/photonmass.htm
http://www.ibiblio.org/lunar/school/library/massph ot.html

Most texts I've read state simply that photons have no mass. Those that disucss the topic in depth usually indicate that most phycisists believe that photons do not have mass. Just because someone didn't have the same schooling/texts as you does NOT make them ignorant.

Oh, and for what it's worth, GWB was educated by Yale and Harvard. Too bad he didn't have the benefit of a quality education like one might receive in Texas.

• Lofstrom Loop
• Modular Laser Launch
• Hypersonic Airplane Space Tether Orbital Launch (HASTOL)

Another thing these projects do is teach the science and engineering community how to federate their technologies. This federative engineering requires both advanced technical skills and federative social and political skills (the latter being what America increasing lacks).

Pop Quiz Question:: which is longer:

I could hardly believe it, but the two manuals are of comparable length.

PS: the Saturn V manual is 15 MBytes, so I hope NASA doesn't get too slashdotted.

No, I didn't give any supporting links because I wouldn't know where to begin...

We're talking about thousands of scientific papers going back to the 1930's....

Instead, here are some links to some non-technical introductions:
http://map.gsfc.nasa.gov/m_uni/uni_101matter.html
http://astron.berkeley.edu/~mwhite/darkmatter/dm.h tml
http://pancake.uchicago.edu/~carroll/cfcp/primer/d ark.html
http://www.astro.princeton.edu/~dns/MAP/Bahcall/no de2.html#SECTION00020000000000000000
http://zebu.uoregon.edu/text/darkmatter.txt

No, you probably won't find technical details in these sources, but many of them contain links to more detailed information.

Also, as much as I find your dismissive attitude obnoxious, I am happy to help you explore the actual evidence for dark matter. Feel free to reply to this post with any actual questions.

Doug

What is cause for concern are the number of critical tipping points we seem to be hitting. Specifically:

• Melting permafrost to release billions of tons of methane - as the northern reaches thaw, trapped methane and carbon dioxide is released. The methane is of particular consequence since it is a much stronger greenhouse gas and persists much longer than CO2 does. As more permafrost outgases, the temperature rises and bakes even more of the frozen north. There is even bi-partisan acknowledgment and concern over the problem. Alaska is literally melting
• Loss of polar sea ice changes albedo - warming sea waters melt ice faster, as the surface of the earth in that region changes from reflective white to darker colors more heat is retained, in turn melting more ice.
• Global warming to speed up as carbon levels show sharp rise - this is BIG news. Why? Because there's no corresponding relative increase from human emissions or other known sources. The implications are that we've tipped a balance with CO2 and triggered a feedback loop. Even if we ceased all industrial activity today, the natural source might continue until the planet is again uninhabitable for oxygen-breathers.
• Those paranoid wackos at NASA have also noticed problems if the ocean currents shift which some reports say has already begun.

It's not that things might get a bit warmer (or colder), or that a "few people" in low-lying areas might have to move (actually, it's 53% of the U.S. population according to the census). What's really scary is that we are changing the atmosphere on a scale that may not recover for thousands of years if ever, and which has no guarantees of being suitable for higher life.

Actually, a human has been exposted to vacuum, at least partially, during a test (on accident). The link goes to Nasa's ask an astrophysicist answer to your question. It is an interesting read, even if it does dispell my childhood view of boiling blood and exploding eyeballs, ala Total Recall :)

Of course! That's no moon, it's a space station. Its defenses are designed around a direct large-scale assault. A small unmanned probe should be able to penetrate the outer defense.

Um dude, O'Keefe has been gone from NASA for nine months now, your article link is almost a year old. One of the first things that the new administrator Michael Griffin did when he took over the reins was to try to figure out ways to keep Hubble alive. Griffin's an actual scientist, unlike O'Keefe who's a career-track manager. And thus sees the important of Hubble, which has been indispensible for astronomical research.

Direct from NASA's Hubble page , it says

"At his April, 2005 confirmation hearing before the U.S. Senate, as well as in subsequent statements, new NASA Administrator Michael D. Griffin testified to the extraordinary scientific value of Hubble. He indicated his desire to take the robotic servicing mission "off the plate" on the basis of mission complexity, and reconsider an SM4 Shuttle-astronaut mission to Hubble. His rationale is that after the Shuttle's Return to Flight ("RTF", currently scheduled for July of 2005), and in particular after all the Shuttle improvements that precede RTF, NASA will essentially have a "new" Shuttle vehicle and system in the context of astronaut and mission safety. After successes in RTF and the following flight, if analysis shows that the risk levels associated with a Hubble mission are sufficiently low and manageable, SM4 could be reinstated by the Administrator."

Consider this fact: In the air we breathe, each cubic centimeter contains roughly 5 X 1019 atoms. In contrast, the intergalactic medium has a density of only 10-6 particles per cubic centimeter--each atom inhabits a private box a meter on each side. This would seem to suggest that there is not much matter in the intergalactic medium. But, given the enormous volume between the galaxies, it quickly adds up: The combined atomic mass of intergalactic gas exceeds the combined atomic mass of all the stars and galaxies in the universe--possibly by as much as 50 percent! There is indeed something in empty space

Show some respect, AC Troll. Space exploration or not, disease, war, poverty, and economic forces will always exist.

Most people understand that research for the sake of increasing knowledge will inadvertently lead to the researcher learning something that he "didn't know he didn't know." This results in new approaches to problem solving, new ways to cure disease, new reasons to have wars, etc. Cruise this site to see some of the items that resulted from NASA research. You might learn something you didn't know.

is it me or people in this photograph in the cleanroom have no biological hazard suits!!

http://www.nasa.gov/mission_pages/stardust/multime dia/cleanroom-1.html

i mean what if there are some extra terestrial viruses that got caught in the sample?!

bird flu will be the least of our problems then!

Where do I collect the one with my name on it?

re: http://stardust.jpl.nasa.gov/overview/microchip/fa q.html

From NASA press release:
"I have been waiting for this day since the early 1980s when Deputy Principal Investigator Dr. Peter Tsou of JPL and I designed a mission to collect comet dust," said Dr. Don Brownlee, Stardust principal investigator from the University of Washington, Seattle. "To see the capsule safely back on its home planet is a thrilling accomplishment."

NASA has posted a few pictures and press releases.

Congratulations to all involved.

From NASA press release:
"I have been waiting for this day since the early 1980s when Deputy Principal Investigator Dr. Peter Tsou of JPL and I designed a mission to collect comet dust," said Dr. Don Brownlee, Stardust principal investigator from the University of Washington, Seattle. "To see the capsule safely back on its home planet is a thrilling accomplishment."

NASA has posted a few pictures and press releases.

Congratulations to all involved.

I don't see them dropping down with clotted blood yet.

Then again, they didn't open the capsule - and who knows what happens when they bring it to the doctor and he doesn't run a lunar lab...
(btw thanks for copying my comment ;=)

It's an overlapping set of responsibilities.

The FAA doesn't want you to use your cell-phone during taxi, takeoff, and landing because of anecdotal evidence that they can screw up various electronic systems of the airplane. While you're in the air, the FAA doesn't have a problem with it unless it messes up the airplane, at which point someone will come back and tell you to turn it off (depending on how curious they are and how much time they have, they might try to figure out which device was the problem).

The FCC doesn't want you using your cell-phone while in-flight because some cellular systems were not designed to deal with passengers being able to see all cell towers while traveling at over 400 miles per hour. I don't know the details, just that it can mess things up. The FCC has no problem with you using the cell-phone during taxi, take-off, or landing because you're going slowly and you're at low altitude, and you're probably not going to confuse the cellular systems.

So, if the FCC drops their complaints about cell-phone use, you will be able to use a cell-phone while in-flight, but not during take-off or landing.

For a chuckle, take a look at this PDF on "Passenger Electronic Devices" from NASA: http://asrs.arc.nasa.gov/report_sets/ped.pdf

When do we reach that point when the public is too wired?

The problem isn't being "wired," the problem is that you're picking up cross talk.

This technology, then, should interest you: Subvocal speech recognition.

In the not too distant future, we should be able to communicate with people without actually voicing our words. Just moving our mouths, and perhaps not even that, will be all that's necessary.

From Harrison Schmitt's bio at Nasa (http://www.jsc.nasa.gov/Bios/htmlbios/schmitt-hh. html):

"On his first journey into space, Dr. Schmitt occupied the lunar module pilot seat for Apollo 17 -- the last scheduled manned Apollo mission to the United States" ...

I wonder if he found it ...

Do not worry about your difficulties in mathematics, I assure you that mine are greater. - Albert Einstein

I have learned that you can do wonderful and amazing things with machines and math, but machines themselves will never reproduce the creativity, insight, and wonder of the human mind.

Remember the mars rover was hamstrung for awhile with a flash problem.

It's true that the mars rovers uses flash, but the problem one of the rovers suffered can hardly be called
a "flash problem". It was a file system problem. The FAT they used on the flash had a limit to how many files it
can hold in one single directory. http://marsrovers.jpl.nasa.gov/newsroom/pressrelea ses/20040201a.html.

A colder stratosphere in 1998 and 2005 (relative to the warmer troposphere in the active months) allowed greater cooling of ice in the eyes of major hurricanes. Whenever the up flows of ice hit the down flows of ice falling from partially collapsed eyes it produced lightning.

http://www.ghcc.msfc.nasa.gov/MSU/hl_temp_glbave.h tml

http://science.nasa.gov/headlines/y2006/09jan_elec trichurricanes.htm?list749825

I predict the 2006 summer temperature anomaly differences between the global troposphere and stratosphere temperatures will remain high yielding a troposphere which is over 1 degree Celsius warmer than the stratosphere on average, to produce additional major hurricanes with lightening.

Temp_tropos_1998 = +.65 degrees C
Temp_strato_1998 = -.40 degrees C
delta_1998 = 1.05 degrees C

Temp_tropos_2005 = +.30 degrees C
Temp_strato_2005 = -.75 degrees C
delta_2005 = 1.05 degrees C

Prediction:
Temp_tropos_2006 = +.40 degrees C
Temp_strato_2006 = -.65 degrees C
delta_2006 = 1.05 degrees C

A colder stratosphere in 1998 and 2005 (relative to the warmer troposphere in the active months) allowed greater cooling of ice in the eyes of major hurricanes. Whenever the up flows of ice hit the down flows of ice falling from partially collapsed eyes it produced lightning.

http://www.ghcc.msfc.nasa.gov/MSU/hl_temp_glbave.h tml

http://science.nasa.gov/headlines/y2006/09jan_elec trichurricanes.htm?list749825

I predict the 2006 summer temperature anomaly differences between the global troposphere and stratosphere temperatures will remain high yielding a troposphere which is over 1 degree Celsius warmer than the stratosphere on average, to produce additional major hurricanes with lightening.

Temp_tropos_1998 = +.65 degrees C
Temp_strato_1998 = -.40 degrees C
delta_1998 = 1.05 degrees C

Temp_tropos_2005 = +.30 degrees C
Temp_strato_2005 = -.75 degrees C
delta_2005 = 1.05 degrees C

Prediction:
Temp_tropos_2006 = +.40 degrees C
Temp_strato_2006 = -.65 degrees C
delta_2006 = 1.05 degrees C

JPL Visualization Supercomputer

... when they have their own 'distro' designed for spacecraft:

http://flightlinux.gsfc.nasa.gov/

The article isn't very clear on why matter traveling rapidly toward a black hole would still take a long time to fall in. I assume they are refering to the gravitational time dilation effect.

Conversely, someone falling into the black hole (ignoring for the moment that he would in fact be ripped apart by tidal forces) would see the entire history of the universe played out above himself as he fell in.

Where is Stardust now?

They seem to use aerogel for this. It's so cool material woot!

I'd buy it, even if it's mostly just air.

How many people are in both catagories?

Admittedly the search was for larger objects on Mars than the tiny flecks of space stuff from this mission.

So, if there is a "googling" action, also is there a wikipedin action?
The Wikipedia entry about Event Horizon has an interesting "faq" about, orbitig the event horizon and sticking you hand into the event...
Also the wikipedia companion, talks about Stephen Hawking saying that no "event horizon" can be formed at a black hole... This article needs edition... :)
Good reading before a good sleep...
Btw, there is a neat animation about a neutron star X-ray burst


enough of karma whoring...

Well fie on them - Google doesn't own any satellites last I checked.

Actually, google does own a satellite. I believe they got it when they purchased Keyhole.

For example, Big Bang cosmology dominates science and dictates a lot of our decisions one way or another, yet relies upon many unproven (in some cases disprovable, such as the matter of the highly redshifted quasar sitting between us and NGC 7319 in Stephan's Quintet [innermost of the pair at 3 o'clock]) assumptions.

There are also a number of Islamic scientists from a millennium ago (plus or minus) and Greeks from a couple of millennia ago who would be somewhat put out by your assertion that science as we know it is somehow new. They were probably a bit short on linear accelerators, electron microscopes and compute farms, but the principles were all there. I'm sure that if I was a better historian or archaeologist I could flood you with more examples, but I think two is enough to make the point.

What do you suppose those 2 small spherical objects are in the pic? hi-res pic: http://www.nasa.gov/images/content/122706main_hurr icane_emily1.jpg

This just furthur backs the theory that people now have the ability to spawn (and destroy) hurricanes at will using scalar weaponry and resonating EM-energy beams.

The stage is now set for a long winter:
http://www.weatherwars.info/

quoted from http://science.nasa.gov/headlines/y2006/09jan_elec trichurricanes.htm :
Indeed, the electric fields above Emily were among the strongest ever measured by the aircraft's sensors over any storm. "We observed steady fields in excess of 8 kilovolts per meter," says Blakeslee. "That is huge--comparable to the strongest fields we would expect to find over a large land-based 'mesoscale' thunderstorm."

Lately I have been reading the Apollo lunar surface journal. I am up to Apollo 15 which included Dave Scott on the crew. I find it totally wierd to read lines like:

115:31:01 Parker: Roger. Morning, Dave. Waking you up an hour early because we've got a little problem on-board we need addressed.

My mind always fills it in with something about the AE35 antenna pointing module.

The Hubble already has a repalcement in the works. It is called The James Webb Space Telescope and is scheduled to go up in 2013. More about the JWST

I found this on NASA's web site: http://imagine.gsfc.nasa.gov/docs/teachers/lessons /xray_spectra/background-elements.html

It suggests that heavier atoms are created during supernovae, as well as in the ISM during "day to day operations." Maybe the relative lack of heavier atoms in space has something to do with the fact they are all sucked into black holes?