Catch up on stories from the past week (and beyond) at the Slashdot story archive

 


Forgot your password?
Close
typodupeerror
×
Space Science

Iridium Repurposed For Science 40

Posted by Hemos from the well-at-least-someone-is-using-the-darn-things dept.
Elvis Maximus writes " An article in today's New York Times describes how Iridium satellites' orientation sensors are being used to track currents in the Earth's magnetic field." The NYC Times, of course, wants registration info, so you'll have to make another account - but it's good to see at *someone* is using Iridium, cuz the customers certainly didn't.
This discussion has been archived. No new comments can be posted.

Iridium Repurposed For Science More

Iridium Repurposed For Science

Comments Filter:
  • "Repurposed"?

    Somebody please smack the jack-ass who came up with that brown-noser term. Ugh!

    Can anybody else smell another round of make-believe boardroom scrabble coming at us at light fucking speed?

    Sigh.

    Fantastic Lad -The most amazing script-kiddie of them all!

  • Didn't the Iriduim system have a competitor that was backed by microsoft what happened to them are they still a going concern or have they gone bust as well?
  • The NYC Times, of course, wants registration info, so you'll have to make another account

    Ive simply stopped reading articles that link to the NY Times. I suggest /. stop linking to their articles - 'we' are only encouraging them to continue this 'login' madness by sending them the /. hordes day after day. Instead of sending them readers - i suggest everyone click this link: http://www.nytimes.com/slashdot-users-hate-your-lo gin-crap_free-the-net.html [nytimes.com]. Put 100,000 messages like that in the logs and someone at NYTimes will notice.

    Attention /. 'editors': Please STOP linking to NY Times articles as long as they continue this 'free-login' garbage.

  • From what I gathered of the other article (New Science or something like that?), the reason the satellites are still operational had nothing to do with Motorola being good fellas for the scientists' $72 million, but rather the fact they had a contractual obligation to fulfill with the DOD. Motorola certainly does not wish to upset one of their largest customers. When that contract is over, if there isn't someone else to pick up the ball, they probably will drop the satellites into the ocean.

  • Ahhh, now we don't get to see these clad of satellites come dropping to the earth with pin-point inaccuracy. I was hoping to see havoc with these little fellers. But just wait they can't stay up there forever...or can they?

    Besides the gov. is just using them for personal telecommunication purposes...also the United States is really free...no really I beleive so. YFR

  • >But 50 billion Watts? Imagine if we could
    >directly harness some of that energy!

    You mean in the same way that we harness solar power? - by putting a couple of dozen solar power plants in the world and still using archaiac coal, gas and oil power in the majority of the world.

  • My god, you're serious. Are you kidding me? Do you really think the Slashdot readership makes up very much of the New York Times online readership. Hint, it doesn't. Here's another hint, what is the problem with the free login. Sure, it's annoying, but speak for yourself, I don't hate it. Free the net? What kind of crap is that? Maybe if you read a few other posts, btw, you would know that you can just change the www to channel and ignore the whole process.

    People like you sicken me; you act like something like this is a direct attack on your personal freedom and must be stopped. How about this? If you don't like NYTimes, you don't click on the links? I happen to like their content, so I want Slashdot to continue posting stories from them.
  • Can't provide a movie for the currents yet, but we do have one for the global potential measured by SuperDARN. Brian uses that in combination with the mag data from Iridium to find his currents: http://superdarn.jhuapl.edu/map/index.html Not all space science is done from orbit :-).
  • Amazing - there's more coverage in the least populated area of land on the planet than anywhere else! The poles, that is.
    I would have thought that tipping the planes toward the equator more than the ferw degrees they appear to be would have been more efficient.

    FP.
    -- Real Men Don't Use Porn. -- Morality In Media Billboards
  • Reply/Moderate Up/Reply/Moderate Up

    Sorry, you "lose"!

    Sure post more, e.g. how was the choice of the 6 orbital planes made, and how likely is it that you'll need to be handed over to a satelite on a different plane?

    FP.
    -- Real Men Don't Use Porn. -- Morality In Media Billboards
  • Item #5528252355
    NO RESERVE! 70 sattelites, geo-synch orbit. LIKE NEW! Sattelites can be used for relaying voice transmissions in wilderness areas, detecting changes in magnetic field of the Earth, or RAINING FIERY DEATH ON YOUR ENEMIES once you destabilize their orbit. Pics available at my web site. This project had burn rate in the BILLIONS OF DOLLARS, do not miss this sale!!!!! Don't wait, CALL NOW at 1-800-SKY-FALL for more info or other great deals!
  • You are both wrong. The answer is neither to avoid them completely or to roll over simply because they want to place controls on how you can view and use the information on their page.

    Ever since they started spreading stories out across multiple pages, I have been planning a program to get around their broken ideas of presentation. What I want to do is write a script using perl and lynx to download the complete nytimes everyday, in a one-page-per-article format, with a single big index page that links to all the articles, and archive it on my disk.

    This could be set to run at 3am every night, making for much speedier consumption of the times when I get up in the morning, making my day a tiny bit more efficient. The fact that you would build up a searchable archive of the paper over time would also be highly useful. Who wants to pay two bucks for an article just because its a week old ?

    You'd have to maintain the script against their periodic redesigns. If I ever get the energy, I'll do it one weekend and then post it on freshmeat.

    The reason why I this would solve the account/privacy/tracking issue, is that I'd make it have a rotating set of accounts and it would use a different one for each article. There would be a simple text file with "account_name password" format, so that people could trade and merge these files, totally screwing tracking because random stories would be loaded from each account from different machines.

    I guess my moral is that if you care, no one can put content on the internet and also control and meter access and use. All you have to do is sit down, and write the program that makes it easy for all the idiots out there to do what they want.

    One last thing -- if they'd put all their articles on a news server I'd never visit the web page, I think the news group format is best for fast efficient consumption of the morning paper (well, best electronically -- I still cannot read the same amount of information as I can if I have the actual printed version in hand.)
  • I was talking to a previous sales person for Iridium .. she says that phone calls rarely lasted more than one handoff .. she says the sattelites would hand off the call with no ACK, so if the signal didn't bounce properly, the call was lost, which happened frequently.

    I have NO proof to back this up, just the word of a salesperson, so attack me not.



    We emerge from our mother's womb an unformatted diskette; our culture formats us.
  • Yep, you're right. Thanks for the correction. I was wondering how they got good enough coverage with them spaced so far apart.
  • Perhaps zania can correct me if I'm wrong, but I believe the reason for the 6 planes was that was what it would take for adequate coverage of the globe. Actually, I think there were originally 7 planes but they scaled back to save money.

    As for switching to birds on other planes, I think the probability is low unless you're in motion and cross from an area covered by one plane to one covered by another. More likely you would switch to the one following along behind it as the old one goes over the horizon.

    One way to visualize this is to view the Earth from one of the poles and imagine 6 lines crossing the poles at 60 degree intervals. These are the six orbital planes. There 11 sats in each plane moving along in single file. So the worsst case coverege area is at the equator where the planes are spaced farthest apart.

    I made all this up, so I really hope it's right. Someone jump in and straighten me out if not.
  • You make no sense. You say the military has not done anything in our personal interestes (so you must be american), there not supposed to do anything but defend our country and to ensure our freedoms. Then you bitch about threats to american society, now your not an american, or else you should be glad they're protecting our "american society". Then you get into a rant about the fbi and waco, the fbi is not controlled by the pentagon and waco was a disaster by that stupid unqualified attourney general who's out in a couple of months. Lay off the LSD. ben

  • Although I thought it was too bad that the Iridium venture didn't work out, I was glad to hear that the sattelites could be salvaged to do some usefull work. At first I had heard that the military had purchased them, and I was afraid that they would be squandered into some useless project.

    But now, we can get a nice big map of upper atmosphere electromagnetic interactions! Wooo! What would be nice though is to see some dynamic graphics of the atmosphere EM data. If somebody has a link to this data or the results, I think it would be usefull to post it here. I'd like to know how much the data changes, and what it looks like.

    Once again - good save in the name of science...

  • Speaking of science, how do astronomers feel about having to put up with continued flares [eu.org] now that Iridium has been "rescued"?

  • Oh come on people (Score:1)

    by Anonymous Coward

    Anyone that can manage to be fooled by these rediculous claims that the Pentagon are allowing scientists to use the Iridium network needs to seriously take a look at the naivety of their political viewpoint. Since when has our military ever done anything that did not serve it's interests, and pure science is certainly not something that they would be interested.

    No, in fact these so-called "scientists" are nothing more than a front for the combined resources of the Pentagon and shadowy organisations like Handgun Control Inc. whose ultimate aim is to remove your personal freedoms in the name of the Federal Government. Using the Iridium network as a sophisticated spy network, these people can hunt for people deemed as "class one threats" to American society - survivalists, and religious groups primarily. When the network detects a target, a computer system located in Berkeley is updated with the information, and a dossier passed onto FBI contacts.

    How else do you think that the FBI determines which groups to target? If you think that Waco was the result of anything other than sophisticated orbital surveillance then you are living in a fantasy world where the government upholds the Constituion and liberals are tolerant of other beliefs. This is just another step in the long history of the erosion of our Constitutional rights by leftists in our once great and free nation. Today, if you don't fit the stereotypes, you are likely to be deemed a danger to society.

  • Can't beat the price ... (Score:4)

    by funkman ( 13736 ) on Tuesday December 19, 2000 @04:06AM (#549430)
    How many science projects can get 70 satellites for $72 million? Almost 1 million per satellite. You couldn't get a better a bargain than that even if it were on ebay.
  • >> Welcome to Iridium Network 1.04. [suup@iridium-network] su Sorry! Seriously, it is good that they're doing something with these satellites instead of turning them into a super-expensive fireworks show.

  • Re:NYTimes login information - Actual text (Score:3)

    by beebware ( 149208 ) on Tuesday December 19, 2000 @04:12AM (#549432) Homepage
    In fact - to save you even having to login, here's the data:

    Motorola spent billions to create the Iridium satellite telephone system, allowing anyone almost anywhere to make a phone call. Unfortunately, not many people found much reason to lug a cumbersome phone to a remote place and pay several dollars a minute for the service.

    Scientists, however, found a very good use for it.

    With the help of Iridium's constellation of more than 70 satellites circling 470 miles above the ground, the scientists have collected a bounty of information about electric currents in the upper atmosphere, data they could not have obtained otherwise.

    "We need measurements to make the invisible visible," said Dr. Brian J. Anderson of Johns Hopkins University's Applied Physics Laboratory in Baltimore, who led the effort.

    The sun spews out charged particles traveling at a million miles per hour known as the solar wind. The bombardment of the solar wind would be deadly to life on Earth, but Earth's magnetic field deflects the streams of charged particles -- electric currents, in essence -- and either deflects them around the planet or channels them toward the North and South Poles. The currents themselves cannot be seen, but they power the colorful, flickering nighttime display of the aurora borealis -- what in the Northern Hemisphere is known as the Northern Lights -- and the aurora australis in the south.

    When the sun sends out a strong puff of charged particles, these auroral currents can disrupt radio signals, damage power grids and puff out the Earth's atmosphere to drag down satellites. The new knowledge should help scientists better understand such "space weather."

    The orbits of the Iridium satellites pass directly over the North and South Poles, providing an ideal downward observing perch of the polar regions. Several years ago, Dr. Anderson realized that the magnetic sensors that the Iridium satellites use to orient themselves are sensitive enough to detect the 1 percent fluctuations in the Earth's magnetic field caused by the auroral currents.

    Since February 1999, the operators of the Iridium system have been shipping the magnetic field data to Dr. Anderson and his collaborators, who then calculate the position and strength of the currents. The large number of satellites means they can detect fairly quick shifts in the currents. A second, ground-based system provides a complementary snapshot of the auroral currents.

    Eight radar dishes in the Arctic known as the Super Dual Auroral Radar Network, or SuperDARN, measure the electric fields emitted by the charged particles. Multiplying the electric fields measured by SuperDARN with the magnetic fields from Iridium tells how much power is flowing into Earth from the solar wind. The data showed that the power flow was often concentrated in "hot spots" and could change quickly. On one day in March, the power jumped from 17 billion watts to nearly 50 billion watts in two hours.

    "They are much more complex than we thought previously," Dr. Anderson said.

    For now, the flow of data coming down from Iridium continues, but it may not last long. A partnership set up by Motorola to run the satellite system went bankrupt in August 1999 and had announced in March that it was going to shut down the satellites and crash them into the ocean. But a new $72 million contract from the Pentagon will keep the satellites up for at least two years.

    Even if Iridium is eventually ditched, the collected data could enable scientists to estimate the currents based on the brightness of the Northern Lights.


    Richy C.
  • All of the sudden, I'm seeing dead companies rising out of the grave and "refocusing" their strategies. B2B is the usual goal for being repurposed, but a network of communications satellites repurposed for scientific research? That's certainly a new one. Maybe some of those companies on FC [fuckedcompany.com] can take Iridium as an example.
  • I wonder...there are quite a lot of those sattelites and since they have such a low orbit, I suppose they go rather fast...I suppose this means that during a phonecall, one will have to switch sattelite quite often...does anybody know how this is done? I also wonder how they calculated those orbits; I suppose they all fly in different directions, but to keep the whole earth covered must be a hell of a job! Does anybody have some info on this?
  • Okay, who's been couting? Have we had more Napster or Iridium stories?

    Holy Hell, Iridium is up and down more than an 18 year old in a whorehouse!

  • Iridium flares can be predicted. Besides, there's only a short time when they're even seen regularly: dusk and dawn. Astronomers will have to deal with the ISS' flares, too.


  • New Scientist has also some coverage (Score:4)

    by Anonymous Coward on Tuesday December 19, 2000 @04:13AM (#549437)
    Look here [newscientist.com]

  • Re:I wonder... (Score:3)

    by zania ( 254748 ) on Tuesday December 19, 2000 @04:44AM (#549438)
    They are in six orbital planes, 11 operational satellites per plane, with a few spares here and there. In LEO (low Earth orbit) their orbital period is about 90 minutes, which means that for any given user, a satellite will be overhead for maybe ten minutes max before having to switch off to another satellite. Since the Iridium phone is omindirectional, the new satellite just has to take over the CDMA signal and you get to keep on talking. Since the satellites are usually beaming the signal among themselves to a satellite over a downlink station, it isn't too hard to take one out of the loop and put another in. Hope that clears things up. Can post more if this isn't already over the heads of most readers here.

  • Not really - the article clearly says this has been going on since the start of last year (the military buying Iridium out will hopefully allow this to continue a bit longer.)

    But 50 billion Watts? Imagine if we could directly harness some of that energy!

  • We should have a 'Iridium' topic instead of bundling it all into Science - just so we can 'deactive' the stories showing...
    Richy C.
  • Similar to the technology involved when driving a car and talking on a cell phone (behaviour that is common but that I find abhorrent, driving a car, that is).

    Boycott Coke!

  • For once I hoped we could have a NYTimes acticle without someone mentioning this, but not this time.
  • Who needed orbital surveillance for Waco anyway, when anyone who fancied could fly a helicopter over the site?

    As for how the FBI decides who to target - well, if you stand up in public and shout "Unbelievers are evil and must be killed", then expect to get some attention!

    Either Troll City, or Looneysville. One or t'other...

    Grab.
  • I second RiffRaff's opinion. The flares aren't really a problem and they only occur shortly after dark or just before dawn. The problem was the frequency band they operated in interfered with radio astronomy. I don't know if this is still the case or not, but I would assume that in it's new role, the sats could share the airwaves with the radio astronomers more peacefully.
  • I was always wondering why they didn't reposition for high speed internet - there are lots of people who don't get cable or DSL lines and would love to be able to get reasonably priced access to the internet. Starband is doing something like this, but I don't know much about it (got DSL myself).
    It would also be a salesperson's dream, as you could haul around the transceiver as part of a portable computer setup and then it wouldn't seem too bulky (or at least the tradeoff would be worth it). I (co-)wrote a paper in a college tech writing course where one of our goals was internet anywhere for our sales force and we thought Iridium would be the choice for it (this was when only about 1/2 of the satellites were up). I really think Motorola dropped the ball on this one. Then again, maybe the network can't handle high speed data transmission.
  • Sorry bollixed up the url, it should be:

    SuperDARN Convection Maps [jhuapl.edu]

  • Thoughts on Iridium (Score:4)

    by dgb2n ( 85206 ) <dgb2n@yTWAINahoo.com minus author> on Tuesday December 19, 2000 @06:09AM (#549447)
    As one of those "lucky" few who actually tried out the phones, I wanted to pass on a few thoughts.

    The Iridium system ultimately failed commercially because it just didn't perform. Sure you could do some neat stuff with it (as we actually tested such as call in flight between planes by pointing the antenna out the window) but get the darn thing anywhere near a built up area such as a city and it had trouble picking up a satellite. The plan for the system to use local wireless phone systems where available (such as GSM in Europe) just didn't work as advertised. $7 per minute doesn't cut it. There just aren't enough people who operate outside wireless system footprints who can affort the price to make the system commercially viable.

    With so many satellites threatening to just burn up in the atmosphere, I'm in favor of whatever good usage can be made of this system. There have been a few posts complaining about the military's use/buy out of the system and I think they're dead wrong. If the military had not stepped in with funding to keep it aloft, there might not have been any scientific use of the system at all.

    The military will use Iridium, ironically enough, exactly how it was intended: for quick phone service outside areas where other commercial wireless phones don't work. Up until, the military relied heavily on INMARSAT which was bulky and for which military use was not really permitted under the usage agreement and bylaws.
  • The usual Problem with SatCom technology:

    - Even with dedicated internet satellites, delays up to the 500ms range severely limit some of the funkier recent Internet applications. Nice bandwidth though.
    - Iridium is managing to double its data rate to *gasp* 19200 Bits/per second. This means 100 Units or something to get to DSL/Cable speeds (Cellphones have the same problem)

  • Use channel.nytimes.com (Score:4)

    by fhwang ( 90412 ) on Tuesday December 19, 2000 @04:24AM (#549449) Homepage
    Getting to the stories through channel.nytimes.com allows you to see the stories without registering. Here's that Iridium story [nytimes.com].

  • imagine 6 lines crossing the poles at 60 degree intervals

    Make that (idealized) 30 degree intervals. There are 6 planes, cutting mother earth into 12 pieces of cake...

    http://www.ee.surrey.ac.uk/ [surrey.ac.uk] has a nice picture for the imagination impaired.

Slashdot Top Deals

"When the going gets tough, the tough get empirical." -- Jon Carroll

Close