Satellites in collision; Watching satellites gone astray: ZS1BI in the news
The first amazing news (http://www.space.com/news/090211-satellite-collision.html) is that the Iridium-33 satellite was obliterated by a highly improbable collision with long-dead Soviet Cosmos-2251 satellite ~800 km over Siberia.
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Totally unrelated, except for the news appearing on Space.com: one of our old-time AMSATers is also in the news on Space.com. The Feb. 5th edition carried a very interesting article on a long-time AMSAT supporter, Greg Roberts, ZS1BI. For those of you who don't know Greg, an interesting Hearsat "Ask The Expert" autobiographical (& how-to) article can be found at http://www.hearsat.org/content/ask-expert-greg-roberts.
For many years Greg was a well-known Variable Star Observer http://books.google.com/books?id=NoHxiPAkptYC&pg=PA367&lpg=PA367&dq=%22greg+roberts%22+SAAO&source=bl&ots=W9Z8CWnl2C&sig=1YIcgl5kNbe3LCN9v6hCtj6_ZY4&hl=en&ei=6dWTSf3rC8e_tgfIhKCgCw&sa=X&oi=book_result&resnum=9&ct=result affiliated with the South African Astronomical Observatory (SAAO) in Capetown and has been a very active amateur astronomer, well known for his visual tracking of satellites. See here http://www.saao.ac.za/%7Ewgssa/as3/roberts.html and also here http://www.saao.ac.za/%7Ewgssa/as4/greg.html to see Greg's very interesting notes about visual observing of satellites. A photo of Greg can be seen here http://www.space.com/php/multimedia/imagedisplay/img_display.php?pic=090204-greg-roberts-02.jpg&cap=Master+satellite+spotter%2C+Greg+Roberts+of+Cape+Town%2C+South+Africa..
Greg's most recent visual satellite observing activities are reported on Space.com at http://www.space.com/businesstechnology/090204-tw-satellite-sleuthing.html. But first, some background -- recent news reports (like this report http://www.satnews.com/cgi-bin/story.cgi?number=252590162) tell of the DoD's secret satellite DSP-F23 wandering out of control in Geostationary orbit . The Feb.5 issue of Space.com tells of Greg's optical tracking of DSP-F23 as it flew near the European Astrium-1 constellation. Click here to see this spectacular video clip of the F23 "flyby" produced thru Greg's efforts. http://www.space.com/common/media/video/player.php?videoRef=SP090203_gRoberts&mode= 73 de Tom, K3IO
Simon says
U.S. STRATCOM routinely tracks about 18,000 objects in space, including satellites and debris, that are 3.9 inches across or larger. Tracking priority and "conjunction analysis" - identifying which objects may pose a threat to manned spacecraft - is the first priority.
What when wrong here? Does someone was sleeping on the switch?
NO FAULT IN SPACE Which satellite was at fault, "they ran into each other. Nothing has the right of way up there. We don't have an air traffic controller in space. There is no universal way of knowing what's coming in your direction."
A steel umbrella is probably the best defense?
For those who want to make their own PC game just put theses TLE in your TLE folder and enjoy the show. try a quarter of second automatic play speed. On Orbitron it's nice but could be much better on other interface?
cosmos 2251 1 22675U 93036A 09043.64266265 -.00000921 00000-0 -33225-3 0 7457 2 22675 074.0397 013.7085 0024779 155.8477 204.3811 14.32045077817866 IRIDIUM 33 [+] 1 24946U 97051C 09025.57495122 .00000082 00000-0 22294-4 0 4525 2 24946 86.4003 128.0512 0002243 81.8081 278.3370 14.34215375595154
One more flares producer down!
"-"
Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe WAC BASIC CW PHONE SATELLITE
At 01:20 AM 2/13/2009, you wrote:
Simon says U.S. STRATCOM routinely tracks about 18,000 objects in space, including satellites and debris, that are 3.9 inches across or larger. Tracking priority and "conjunction analysis" - identifying which objects may pose a threat to manned spacecraft - is the first priority.
Key word - "manned". I would certainly hope that if one of the objects were the space shuttle, or ISS, this would have been averted. But - If a central tracking authority saw this ahead of time, what could anyone have done about it? I read the cosmos was out of control. *If* the controllers of the Iridium satellite could alter it's orbit slightly, how would that have affected their bottom line as far as the operation of the entire constellation? Was it cheaper to just let them crash, and then apologize to the space community afterward?
I think this is the new ecology that will need to be addressed, hopefully before it becomes deadly.
73, Rich, N8UX
At 03:27 AM 2/13/2009, Rich Dailey (gmail) wrote:
*If* the controllers of the Iridium satellite could alter it's orbit slightly, how would that have affected their bottom line as far as the operation of the entire constellation? Was it cheaper to just let them crash, and then apologize to the space community afterward?
Commercial satellites are horribly expensive. Almost anything would have been preferable to just letting them crash.
They do station-keeping. (If they didn't, the things wouldn't stay nicely spaced in their constellation, and the Iridium system design depends on keeping the satellites nicely spaced.) Therefore they have the ability to make small orbit changes. I believe that with enough advance notice an adjustment could have been done with a very small amount of fuel. One can only conclude that they did not have advance notice. I doubt we'll ever learn the inside story.
I'll bet they start up an effort to predict future collision possibilities pronto.
At 03:27 AM 2/13/2009, Rich Dailey (gmail) wrote:
*If* the controllers of the Iridium satellite could alter it's orbit slightly, ...
There's a great article in the International Herald Tribune. Unfortunately, IHT has also carried several other articles about the collision with similar titles, so the good one is hard to find. Use this link.
http://www.iht.com/articles/reuters/2009/02/12/europe/OUKWD-UK-SPACE-COLLISION-USA.php
This article discusses the "what did they know" aspect. In fact it says so much that it is confusing. First it says they did not know in advance.
"Iridium didn't have information prior to the collision to know that the collision would occur,"
Then it says they get 400 "conjunction reports" from "US Strategic Command Joint Space Operations Center" per week (ie a notification that an object will pass within 5 km of a satellite), implying that they suffer from information overload.
Then they say the reports aren't any good anyway.
"So the ability actually to do anything with all the information is pretty limited,"
"Even if we had a report of an impending direct collision, the error would be such that we might manoeuvre into a collision as well as move away from one,"
Congratulations to the author for pulling these quotes together. Unfortunately, it still leaves the reader uncertain about what happened.
The first quote may be lawyer-speak. After all, nobody tracks these objects well enough to "KNOW that the collision WOULD occur". That isn't the same as being warned that a one ton satellite is going to whiz by within 5 km.
When the first fellow says "Iridium didn't have information prior", is he saying the DOD missed this one, or is he saying, as in the other quotes, that the conjunction reports aren't accurate enough to take action? Could be either.
I believe that the Iridium satellite should have stopped and yielded to the Russian satellite under north-american driving rules, the vehicle on the left must yield to the vehicle on the right at an uncontrolled intersection... hi
VE6PWN
........ the satellites got PWNed
----- Original Message ----- From: "Luc Leblanc" [email protected]
NO FAULT IN SPACE Which satellite was at fault, "they ran into each other. Nothing has the right of way up there. We don't have an air traffic controller in space. There is no universal way of knowing what's coming in your direction."
participants (5)
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Auke de Jong, VE6PWN -
Franklin Antonio -
Luc Leblanc -
Rich Dailey (gmail) -
Tom Clark, K3IO