After all the hectic of the previous night, I spent yesterday out of house in the dunes and near the beach. Time to pick up now where I left.
NASA has held a teleconference. Basically, they did not report anything new regarding the potential reentry location than what I already reported here based on SSC and Harro Zimmer's conclusions. Note that this NASA map released is basically the same I posted here earlier.
I don't share some of the critique currently levelled at NASA. See discussion at the end of this post.
Okotoks, Canada: a HOAX
The Okotoks (Alberta, Canada) video and report of debris being found (see earlier post here) - news media now report it is a HOAX. Seems I was right with having my reservations. [update 26 sep: more here. The report on wreckage was a hoax created by an aspiring film maker, apparently]
Aircraft contrails being mistaken for UARS
Meanwhile, simple aircraft contrails keep being mistaken for UARS as well: see the previous post and another case here.
Radar artefacts being mistaken for UARS
This one that is doing the rounds, is a mis-interpretation of a very common weather radar artefact. Note how the streak neatly points to the radar origin in the center.
Chinese lantern balloons being presented as "UARS"
As I pointed out in the previous post, footage of Chinese lantern balloons are either deliberately or mistakenly being passed off as "UARS" in the media as well.
Possible confusion with meteoric fireballs
To complicate the picture, there is also the point that "normal" meteoric fireballs appear and can be mistaken for UARS. Multiple such fireballs occur somewhere on this world every day.
Indeed, we had a very nice meteoric firebal (seen by amongst others myself while waiting for the UARS pass) of mag. -5 appear 5 minutes before the 1:37 UTC UARS pass on the 24th. Klaas Jobse has a nice all-sky image of that one here. Yet another one appeared a mere 17 minutes later (video of both fireballs here, again by Klaas Jobse). These were meteoric fireballs, little bits of asteroid or comet debris not related to UARS at all.
While it didn't fool experienced observers like me, laypersons could have easily mistaken it for UARS debris.
Some genuine reports of bright fireball phenomena seen around the predicted reentry time from a.o. Canada, could be such cases of meteoric fireballs. Without clear details on duration and character, it is difficult to discern between these and any potential real reentry observations.
Critique on NASA: I don't share that critique
There is currently a lot of critique on NASA that they can't pinpoint the point of reentry. I think those critiques are unfounded and stem from unrealistic expectations.
All I can say is: people expect too much of NASA and modern technology, notably under the influence of unrealistic TV-series that depict NASA as know-it-alls that can do anything (with just a few computer keystrokes and maybe a hack into a satellite feed here and there typically, according to the TV series that increasingly mold the public's "reality").
But even the best technology and best experts have their limits (and in terms of the actual tracking, this technology is not operated by NASA, but by the US Air Force, by the way), and with the last few UARS revolutions largely over empty ocean devoid of tracking stations, things simply get difficult. There are limits to what models can do when devoid of real-time tracking sensor input.
I might, given time and energy, elaborate on that later in a separate post
5 comments:
Hello, I spot that you'e using Orbitron for mapping UARS ground track.May I ask from where you get best TLE for that prediction? thx
I used a SatEvo propagated version of one of the last SSC released orbits.
The criticism of NASA is justified when it comes to obvious math gaffes - like stating in the same UARS update that the impact happened in the Eastern Pacific and then giving a time interval of 106 minutes that spans more than a complete orbit (that infamous green line in the diagram). It's obvious - from statements made at the telecon as well as from sources I cannot quote in public - that they 'know better' but won't bring down the error bars much for some reason. At the telecon they eventually conceded that to say 4:16 UTC +/- 20 minutes would be o.k. to say, then they didn't put that insight (missed by most reporters) into the press release coming out later.
Much of the reluctance to discuss UARS's demise in an open manner traces back to the military origin of the data on UARS' actual whereabouts NASA had to rely on, of course, and so the blame rests elsewhere. E.g. the question whether IR early warning satellites shouldn't have spotted the reentry heat (and thus pinned down the precise impact spot) has been raised - though not at the telecon, unfortunately - but never addressed.
Still the inability to figure out UARS' final orbit sheds a confusing light - rightly or wrongly - on the state of Space (and general) Situational Awareness in the U.S. Interestingly, since 2008 ESA is working on a complementary SSA system that will eventually involve radars under civilian control - or so I understand the policy. This will become operational only years from now, though, and thus for the upcoming ROSAT reentry (with 1.6 tons surviving) the world has to rely again on the DoD and NASA. Let's see if they do better then ...
People assume NASA is the goto agency for this data, but in reality NASA has almost no ability to track a dead spacecraft.
The folks who do have that ability, and who have the ability to track deorbiting stuff (i.e. warheads) aren't talking and won't be. Those folks only talk to NASA when something might hit ISS or another NASA spacecraft.
Any data NASA gives is based on TLEs and tracking information they get from the DOD. The performance of the assets DOD uses to do this is classified. Any better data we get from NASA will be second-hand.
@ Daniel - I agree with some of the things you say, from a communications and PR point of view, NASA did make some goofs.
It could very well be that they do know more from SBIRS or DSP satellite data: but that stuff is classified. As lordtd said after you and I pointed out in my blog post, it is actually not NASA themselves doing the tracking work - which might tie their hands. And I do think the Air Force / DoD were hampered by the last few revolutions of UARS largely avoiding areas with tracking facilities.
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