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NASA's HETE Coming Down
terrymr writes "NASA expects the High Energy Transient Experiment spacecraft which failed to successfully detach from the third stage of its launch rocket in 1996 to fall to earth within the next few days. While most of the spacecraft will likely burn up in the upper atmosphere there is a good chance that the spacecraft's batteries (weighing 33lbs each) may reach the ground intact. Current predictions put re-entry at 4:41 EDT Sunday April 7 (+/- two days)."
/me wonders whether items will appear on ebay before they even land...
-- ribbit
Hmm..anyone care to explain that?
Does anyone know how to bring this up with NASA's tracking program?
Reminds me of when Skylab fell to earth, dumping pieces of itself over Western Australia. The local president of the town council, Mervin Andre, gave the Director of NASA a littering ticket when chunks of the disintegrating space station dropped over the area southeast of Perth. The ticket remains unpaid to this day, although the council later waived the fine anyway.
"Einstein argued that [...] God is not capricious or arbitrary. No such faith comforts the software engineer." ~ Brooks
The HETE-1 was supposed to look for gamma ray bursts. If you haven't heard about these events, they are believed to emanate from explosions so powerful that they produce more energy in a matter of seconds than the sun will emit in its entire 10 billion years of life.
The cool thing is that astronomers have almost no idea what could be causing these enormous bursts.
Check out http://www.sciam.com/0797issue/0797fishman.html for more information.
It says 15kg clearly in the article which is only a few paragraphs long and takes less than a minute to read.
Maybe you should try that.
Guess somebody's getting a little too specific in their "predictions" given their precision. In other news, today's high will be 67.2 degrees (+/-40).
With all the space junk in orbit now, I wonder if the reason we have not be been contacted by aliens isn't because we are the bad neighbors in the milkyway. We are like the people on the street with uncut grass and old broken down crap strewn all around our yard. Nobody wants to come over and say hello because they assume the residents are low lifes. If we do get a visit, it may be the head of the galaxy association telling us to take down the tacky mood decorations and clean the junk out of our space.
japan. pictures. humor. me
I wouldn't count numbers five and six. Remember, there'a whole lot of zealots who insist we grew out of two people that were made from dirt.
Actually a few more of the questions are rather flawed.
Question 1: No technology currently exists to measure the core temperature of any planet, including Earth.
Question 2: it's just as valid to say that all the oxygen we breath comes nuclear fusion
Question 4: it sould probably contain "relative to each other". Otherwise they move quite a distance each second. Even then you are asking for a true/false about a theory which is imensly difficult to prove.
In other words, the weight of all 4 batteries is 15 kilos, not the weight of each battery. Still, 3.5 kilos at terminal velocity is nothing to sneeze at - perhaps I should buy a large number of pillows from Yahoo!....
www.eFax.com are spammers
'Stainless steel batteries? ' I think not. More likely that they are plutonium or some other nuclear material, and the reason that no predictions are being made about where they will land is because NASA doesn't want to start a panic. As I understand it they are designed to burn up on re-entry to avoid ground level contamination (that says nothing of atmospheric contamination along the flight path). If they survive all the way to the ground and they are radiological....
Space Nuclear Power Systems
Space Nuclear Power System Accidents
Bulletin of Atomic Scientists: How many nuclear devices are there in space?
Link to CNN story.
Or better yet, over a certain corporate campus in Redmond.
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
If they still have control of the satellite, then that is exactly what they do. Remember MIR last year? They deliberately steered it so that it would fall in a large mostly sparsely inhabited area of the southern Pacific.
If you mean would they shoot it down, then the answer is that it is unlikely. We really don't have missiles that can reliably hit orbiting objects yet.
Um, you might want to actually read about the satellite before assuming it uses radiothermal generators.
The great big solar panels in the picture of the satellite might have been a hint that it didn't use nuclear power.
From the HETE pages (describing HETE-2, an exact duplicate of the HETE-1 craft whose launch was unsuccessful):
The HETE-2 power system hardware consists of
You can find more information on the specs of the HETE satellites at http://space.mit.edu/HETE/spacecraft.html .
By comparison, figuring out when an asteroid will hit the earth is a simple matter of determining it's path and speed and doing a simple calculation.
Oddly enough NiCd batteries were used - makes sense really industry standard rechargable batteries along with solar panels.
People keep asking why they don't know when it will hit"
"The re-entry is uncontrolled, and due to potential solar flux variations, time and location predictions will not be reliable until only a few hours before the re-entry event," said Scott Hull"
And contrary to what the original post says, the batteries are not 33 pounds each. That is the total weight of all of them.
Initial analysis indicates that only four small stainless-steel batteries, weighing a total of 15 kilograms (33 pounds) will survive re-entry."
I think it is rather obvious why he chose that target...
there is a good chance that the spacecraft's batteries (weighing 33lbs each) may reach the ground intact
If I'm lucky I won't have to buy that extra laptop battery...
We are like the people on the street with uncut grass and old broken down crap strewn all around our yard. Nobody wants to come over and say hello because they assume the residents are low lifes. If we do get a visit, it may be the head of the galaxy association telling us to take down the tacky mood decorations and clean the junk out of our space.
Or not. Judging from my experience when I leave old junked cars and major appliances in my front yard, it's a great way to make new friends and the encounter would go more like this:
Interstellar pickup truck with interstellar Confederate flag comes up to the edge of our debris field. Occupant gets out, picks his way gingerly down to the surface, knocks on International Space Agency's door.
"Hi there. I wuz just drivin' by, and I was wundrin, is y'all still usin' that there Iridium system you'se've got still orbitin' yer planet? I got sompin' like it at home and I need some parts. Kin I take it off'n yer hands fer a coupla cases of beer? Thank-ye kindly."
Fire and Meat. Yummy.
Here's why I'm making a point of insulting you. Nuclear power of all kinds is backed by a lobby of smug, short-sighted techno-fetishists who just love it in when some hippie does the usual misinformed kneejerk antinuke rant. This allows them to portray all their opponents as such, and avoid the serious issues nuclear technology raise. You just scored one for their side!
All you had to do was make a quick search on Google, which would have led you straight to the specs for the spacecraft in question. Which would have told you that the HETE is powered by a combo of solar cells and nicads.
(Of course, nicads are also an environmental problem, but at least the ones on HETE aren't going into a landfill. Good environmentalist that you are, I hope you take your used nicads to a toxic waste depot. Or is pollution always somebody else's fault?)
Next time you feel inclined to speak up for The Cause, make sure you're actually serving The Cause, and not your own pathetic ego.