tag:blogger.com,1999:blog-1592992209402300549.post2352404789336712614..comments2024-03-29T09:08:47.702-04:00Comments on The Silicon Graybeard: Keep An Eye on the SkySiGraybeardhttp://www.blogger.com/profile/00280583031339062059noreply@blogger.comBlogger22125tag:blogger.com,1999:blog-1592992209402300549.post-63278536430967615862018-04-02T10:43:58.942-04:002018-04-02T10:43:58.942-04:00I've noticed that. I can see it starting reen...I've noticed that. I can see it starting reentry over Tahiti closer to 0016, but the numbers just don't add up right now. <br /><br />Last night, I was trying to keep an eye on news for it, but nobody was doing anything. There were a handful of YouTube Live sessions that were just rebroadcasting the websites I was watching. SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-54423512310989658882018-04-02T10:37:47.060-04:002018-04-02T10:37:47.060-04:00Looks like "official" re-entry was 00:16...Looks like "official" re-entry was 00:16 GMT. Although they claim it splashed down just off Tahiti, and orbital mechanics sez that had to be the time of impact for whatever piece landed there.Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-90820180871090221172018-04-01T19:50:14.319-04:002018-04-01T19:50:14.319-04:00I'm keeping an eye on it. We're well with...I'm keeping an eye on it. We're well within the -1.7 hours that Aerospace says. It's 2350 UTC as I type. <br /><br />It would be cool to see it visually, but that ain't happening for the states. <br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-64217486770771272302018-04-01T18:58:34.953-04:002018-04-01T18:58:34.953-04:00And at 22:11 UTC, SatView updated their estimate t...And at 22:11 UTC, SatView updated their estimate to 00:25 UTC, while the US Stratcom estimate from 21:09 UTC was still 00:48 UTC. Both on 2 April. The SatView debris field would be over Central Africa and the Middle East, while the old US Stratcom estimate would still be over the Middle East, the Stans, and China.Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-13650036612224738692018-04-01T17:39:52.885-04:002018-04-01T17:39:52.885-04:00Important note for other readers following this. ...Important note for other readers following this. That 00:44 +/- 4 minutes is the difference between their stated predictions - one says 0040, the other 0048. They don't bound that with uncertainty limits. <br /><br />Aerospace Corp says 00:30 UTC ± 1.7 hours. <br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-13269805088958142052018-04-01T17:37:11.920-04:002018-04-01T17:37:11.920-04:00Let's hope Stratcom has it right. Ending up C...Let's hope Stratcom has it right. Ending up China would be more poetic. Although vast tracks are lightly inhabited. SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-87646818158693448582018-04-01T17:20:14.196-04:002018-04-01T17:20:14.196-04:00Latest forecast is 00:44 UTC +/- 4 minutes per Sat...Latest forecast is 00:44 UTC +/- 4 minutes per SatView and US Stratcom. Over the South Atlantic which means the debris field ends up over Africa, the Middle East, the Stans, and possibly China.Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-62652365436836944152018-03-31T22:03:28.558-04:002018-03-31T22:03:28.558-04:00On a related subject there will be SSTV from the I...On a related subject there will be SSTV from the ISS Monday and Tuesday. A VHF Scanner and some free software (MMSSTV) is all you need. Terryhttps://www.blogger.com/profile/02693579680266086557noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-27047409158570013912018-03-31T21:43:10.175-04:002018-03-31T21:43:10.175-04:00Heavens Above has it live, too.
http://www.heaven...Heavens Above has it live, too.<br /><br />http://www.heavens-above.com/GroundTrack.aspxdrjimhttps://www.blogger.com/profile/05647484115197408897noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-21969569136885523122018-03-31T16:55:43.375-04:002018-03-31T16:55:43.375-04:00And it ain't "re-entry" that's i...And it ain't "re-entry" that's important anyway. Ain't nuthin' at the re-entry point that cares. It's downrange from there where it gets special. And that's even more difficult to predict than "re-entry". The footprint will undoubtedly extend over a significant area, but the boundaries are defined by mass and drag of the pieces parts as they break up and burn up. Or not...<br /><br />Of course, REAL bad luck would be to be onboard an airliner in the path and get hit by an unfortunate piece. I wonder if the NTSB would call that "pilot error"???Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-64774806025228830542018-03-31T14:10:11.856-04:002018-03-31T14:10:11.856-04:00Thanks SiG I didnt catch that link. Thanks SiG I didnt catch that link. Irishhttps://www.blogger.com/profile/09772405362867585844noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-78830514885384637252018-03-31T10:36:47.986-04:002018-03-31T10:36:47.986-04:00The very first link I posted, to Aerospace, update...The very first link I posted, to <a href="http://www.aerospace.org/cords/reentry-predictions/tiangong-1-reentry/" rel="nofollow">Aerospace</a>, updates on some interval that isn't specified, but has changed several times since I first looked it up. Instead of 1515 +/- 14 hours that it said when I wrote this, it has turned to 2030 +/ 8 hrs. Before I shutdown last night, it was something like 1915 +/- 9 hrs. SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-32377116799428566812018-03-31T10:18:02.081-04:002018-03-31T10:18:02.081-04:00I just knew as I was pressing the button that some...I just <i><b>knew</b></i> as I was pressing the button that someone would call me out on not reducing the area of the earth to that between the latitude limits. I just think that I'm within a factor of two on the odds and that error is far less than the uncertainty in their predictions. SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-29153476511991286622018-03-31T09:34:51.781-04:002018-03-31T09:34:51.781-04:00"And, no, stating the time to the minute when..."And, no, stating the time to the minute when the uncertainty is 14 hours doesn't make sense to me."<br /><br />The expectation value of a statistical prediction is a precise number. The uncertainty value of 14 hours <i>should</i> be identified as the 1 sigma – but only if it's a normal probability distribution. It could be Rayleigh, but they don't say.<br /><br />Statistical theory doesn't lie, but liars use statistical theory. Or something like that. There is no good way to predict the re-entry except at the last moment, when the path can be measured and the drag on the structure estimated by its observed deceleration.Malatropenoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-43688970097108992612018-03-31T09:07:08.194-04:002018-03-31T09:07:08.194-04:00Thanks Mark, I'll check it out.Thanks Mark, I'll check it out.Irishhttps://www.blogger.com/profile/09772405362867585844noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-22411097204272924792018-03-31T08:48:25.586-04:002018-03-31T08:48:25.586-04:00And it looks like SatView expects it to start re-e...And it looks like SatView expects it to start re-entry over China, while US StratCom expects it to start a few orbits earlier off the west coast of Chile. Actual impact will, of course, be downrange from either location by roughly 1/2 hour and thousands of miles.Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-79982589034307672822018-03-31T08:40:37.918-04:002018-03-31T08:40:37.918-04:00Is this:
http://www.satview.org/?sat_id=37820U
w...Is this:<br /><br />http://www.satview.org/?sat_id=37820U<br /><br />what you're looking for?Mark Matisnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-87077842824175805642018-03-31T08:37:36.801-04:002018-03-31T08:37:36.801-04:00You say:
"...could hit anywhere on the 197 mi...You say:<br />"<i>...could hit anywhere on the 197 million square miles of the earth...</i>"<br />but in reality there is very little chance any of it will land outside the coverage of the 42.772 inclination - aero effects on the falling debris would be the only way for any of it to get there. And for <b>LL</b>, I would far rather that it hit the District of Corruption. Or wherever coproach spawn Hogg happens to be at moment of impact....matismhttps://www.blogger.com/profile/12935009854433843094noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-50704282844585922682018-03-31T07:23:26.326-04:002018-03-31T07:23:26.326-04:00Is there a good website that is tracking it live? ...Is there a good website that is tracking it live? Irishhttps://www.blogger.com/profile/09772405362867585844noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-7535339350080035312018-03-30T23:40:42.739-04:002018-03-30T23:40:42.739-04:00Be more like "Urban REMOVAL".....
The n...Be more like "Urban REMOVAL".....<br /><br />The night Skylab came back I was at work drinking beer with my boss, and we were on conference call with several of his buddies who still worked for NASA. They weren't sure then until the last few orbits, as it's extremely hard to get accurate drag numbers on such a complex shape.drjimhttps://www.blogger.com/profile/05647484115197408897noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-5770300771960064662018-03-30T22:55:38.694-04:002018-03-30T22:55:38.694-04:00It would be like the Urban Renewal programs from t...It would be like the Urban Renewal programs from the old days. I bet if it came down in some parts of Detroit no one could tell. <br /><br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-53671927359150542632018-03-30T22:32:05.673-04:002018-03-30T22:32:05.673-04:00Pity about the possibility that it will miss Detro...Pity about the possibility that it will miss Detroit.LLhttps://www.blogger.com/profile/05538854359365988863noreply@blogger.com