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Shuttle Reentry Over the Continental US
TheOtherChimeraTwin notes that the shuttle Discovery will land at Kennedy Space Center on Monday morning at 8:48 EDT. The craft will make a rare "descending node" overflight of the continental US en route to landing in Florida. Here are maps of the shuttle's path if is lands on orbit 222 as planned, or on the next orbit. Spaceweather.com says: "...it takes the shuttle about 35 minutes to traverse the path shown... Observers in the northwestern USA will see the shuttle shortly after 5 am PDT blazing like a meteoric fireball through the dawn sky. As Discovery makes its way east, it will enter daylight and fade into the bright blue background. If you can't see the shuttle, however, you might be able to hear it. The shuttle produces a sonic double-boom that reaches the ground about a minute and a half after passing overhead."
Watch the touch down too! I rewrote the nose wheel steering GN&C module in '89 and the stuff that makes landings "perfect" in '91. They were blowing tires with rough landings. Since then, the touch downs are PERFECT and smooooooooooth.
Hi JV, KM, DC, BW, AR, LP, SM, JY, PP, and the rest of the old GN&C team!
At first I thought those were March X and was going to congratulate NASA on conquering time travel.
The shuttle comes in like a bat out of hell, but I wonder if there couldn't be a more aerodynamic shape it could use to reduce the friction from the atmosphere. The shuttle is like a giant wing catching as much air as possible. It doesn't seem to be the best design to minimize drag...
What should I look for, about 500 miles straight-line distance along the path from the runway?
Last time I had this chance, I think I saw a plane cross the sky, but it seemed too slow.
All my liberal friends think I'm a conservative, all my conservative friends think I'm a liberal.
Looking at the map, it's going to be flying right about over my head. I know what I'm going to be doing tomorrow morning.
Shuttle sonic booms were a perk for me living in LA, whenever it landed at Vandenburg. Those in the path, set your alarms!
1. Well, during re-entry it's not entering nose-first, but belly-first, so the wings basically like air brakes more than like wings. I'm not sure if making it more aerodynamic for flight like an aircraft would actually be an impediment there. It would still have the aerodynamics of a parachute when re-entering belly-first anyway.
2. Well, "glide" is technically accurate, but maybe painting a slightly wrong image for the layman. That thing is losing altitude (falling) at 50m/s (about 110mph or 180 km/h) even in its best glide phase. And it's glide-to-drag ratio is more comparable to a parachute, and I don't mean paraglider, than to an aircraft even at touchdown, during earlier phases let's just say it's got about half as much lift/drag as a squirrel ;)
The angle of descent at touchdown is actually 20 degrees, which doesn't sound like too steep, but it's about 7 times steeper than a commercial airliner landing. By comparison to just about any fixed wing aircraft, it's not akin landing an anvil or the proverbial lead duck ;)
Not saying it's a bad thing, since it does have a _lot_ of altitude and speed to shed, and it's obviously doing a good job at thazt. More like just saying, for the benefit of whoever needs that kind of clarification, that it never actually acts that much like a normal glider, not even on the very last part. Or at least not like a glider you'd want to pilot for fun. All it can do is fall, and quite rapidly at that, just in a more controlled manner. It's a shape to do just one thing: fall down from 340,000m or so (about a million feet) to the ground without going *SPLAT* on touchdown. While techically there is some gliding involved, I think the best description of its role for the layman is more like "rigid parachute" than "glider."
A polar bear is a cartesian bear after a coordinate transform.
I hope the map in the link wasn't meant to be accurate. They misplaced Pierre, SD by quite a ways east of where it is - that's closer to Mitchell, SD :-)
Still, if it's going to pass over Pierre, it should be visible from where I'm at, if I can get up early enough to climb one of the hills here and still make it to work an hour later...
SB
It's old. The more humans I meet, the more I like my cats. At least they are honest.
This is a really neat idea since it might give NASA some much-needed good publicity. That, or it will let those in the midwest/southeast get one last good look at it i the sky before it's in museum.
The weather looks a bit grim for a KSC landing.
Your mama
a) is dumber
b) has a significantly higher volume and mass than our reentry vehicles, and essentially wears quite small amounts of drag
c) enters the atmosphere extremely fat
All in all, often still carrying lots of weight because she's so dense. Where she loses a large part of her mass to ablation, often shatters. We don't want to do that with your momma.
I've seen reentry across Austin (and not the time it broke up smarty pants). Have you ever seen the ISS or a satellite crossing the sky? It looked kinda like that. The shuttle was a bright dot streaking across the horizon very fast, a good 3 times faster than a commercial plane, and left a contrail that hung in the air for a while. Contrail is a misnomer since it stands for condensation trail. What it really is leaving is a trail of ionized gas and ablated material off the orbiter. A minute later I heard a faint sonic double boom.
At the distance you are at, it will be lower, meaning you will have less range you can see it over, so I'd imagine it will still appear to be going very fast (and it will be fast). I think it should be just above supersonic, so you should hear the boom. I doubt it will still be leaving a contrail. I don't think you'll be able to miss it.
If geography allowed it and it made orbital sense to fly over a populated area during every landing, do you think the general population might be more aware and interested in space travel?
If I had an orbital vehicle streaking across the sky every month or so, I would certainly be very aware of the pace of space travel and keep it in my head for longer then I do now.
WOOOOOOOOOSH.
Anyone have a clue why the shuttle would be making a retrograde descent?
You wanta play the dozens, well the dozens is a game. When ablation hits your momma it's a goddamn shame.
Game: Player 'Donald J Trump' now has AI skill level 'experimental'.
will the first path be visible from southeast Minnesota? I'd hate to miss it :(
WOOOOOOOOOSH.
Was that the joke, or just the shuttle? *shakes watch*
So basically over Sicamous BC, then Fort Mcleod AB, and just south of Lethbridge AB. May as well actually name a few places on the flight path, rather than just "Canada".
Can anyone say how close to the path one needs to be in order to see/hear anything?
Any larger maps? Will it be visible from the Seattle area on the first pass?
The first orbit is of great interest, because it goes right overhead (Ft. Peck, Montana.) Need to find out when.
I've fallen off your lawn, and I can't get up.
I seem to remember in Feb2003 the shuttle came across the california coast and flew over Texas and Louisiana. Of course that time it didn't quite make it to Florida...
I believe I'm going to have to throw a giggity on that one--or at least a "that's what she said".
+= E
Are you REALLY that stupid? Or just trolling?
President Obama had nothing whatsoever to do with deciding when the shuttle program would end, that was decided when it STARTED.
If only your god would give you a clue. And as you sow, so shall ye reap.
Hey man! It's been years!
I moved onto the new MCC project, then left to make my millions. I hear they are still having issues with the crapper and someone is actually drinking their piss now. They claim it is to save water.
I heard about the debacle with the "fitting" on the pisser. Seems the prototype you built was - er -- a little small. I told you most men were bigger than THAT. Also, sorry to hear your wife left you the day after you were married. Lot's of other fish in the sea. Perhaps you should look for Asian women?
Pinned to its a tail, a sign reading "Please Donate! NASA"
You can see satellites almost any clear night ANYWHERE on Earth.
GPS satellites are low and cover every point on Earth.
If you look towards the equator, then up, there are hundreds of geostationary satellites for TV, communications and other things about 22,000 miles up. As a reference, the diameter of the Earth is about 6500 miles (I didn't look it up).
The Space Shuttle orbits around 140-180 miles up so it is barely out of atmosphere - some would say it isn't out.
http://www.kowoma.de/en/gps/orbits.htm may be helpful. There's a bunch of stuff to see. With binoculars, you can see a ton of stuff.
At times like this, I wish slashdot would get a few more troll labels. There should be term for a slightly entertaining troll, then there should be a term for this guy whose goal is to tick people off. Some of them make me laugh, and I'd miss them if they left, but this is just sad.
Oh right, stay on topic. Ummm they should fly the shuttle through the volcanic ash, just to show they can do it. It doesn't have any intakes to damage, right? Yeah I know it's stupid for a dozen other reasons. Oh well.
Just watched the shuttle pass over Seattle without re-entry on orbit 222, closely followed by ISS. Next pass will be well past sunrise (6:57).
weather caused a 24 hour delay. will try again tomorrow.
The landing has been postponed until Tuesday (at least) due to rain. Check SpaceWeather for updates.
The first opportunity to land in Florida Tuesday comes at 7:33 a.m. EDT
Landing postponed until tomorrow due to weather at the landing site.
So we're now looking at orbits 237 or 238, I assume?
Here's a great calculator from NASA to determine where to look in the sky and at what time, based on your location:
http://spaceflight.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/JavaSSOP.html
Here in central IL USA, it looks like:
orbit 237: it'll be at a distance of 136 miles at an elevation of 15deg (not bad!) 06:17 local time.
orbit 238: a bust for where I live, never gets more than 2deg elevation.
With the first link, the chain is forged.
SIZZLE.
How many of the tiles on the orbiter are ablative? IIRC, none of them are.
Not ablative in the traditional sense of that is how the TPS works. Bad choice of words on my part. It is foreign particulates dislodging from the body of the shuttle and unintended flaking of the heat shield, combined with impurities in the atmosphere being heated up, that helps make the smoke contrail.
Ground track maps (easy way to see where it's going). These are updated for the opportunities tomorrow. Let's hope it's Orbit 237 or 238 to Kennedy.
http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts131/news/landing.html
NASA TV - listen to see if they are landing on a particular orbit.
http://www.nasa.gov/multimedia/nasatv/index.html?param=public
Applet for viewing data. Put in your location, then on Input tab under Satellite, select orbit and destination you're expecting, KSC237 (ENTRY) for example. It tells you times, directions to look, elevation in degrees above horizon. The higher the elevation and the lower the range the better for viewing and listening obviously.
http://spaceflight.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/JavaSSOP.html
simple, fast homepage with your links: http://www.ngumbi.com/
I wonder if there couldn't be a more aerodynamic shape it could use to reduce the friction from the atmosphere.
Every additional pound of wing is one less pound of payload. The shuttle comes in dead-stick and has no capability to come around for another pass. So enough wing to get it to the runway is all the wing it should have.
As it is (if what I heard from someone in the industry back in the day is correct) the shuttle has FAR too much wing for the mission profiles on which it has been used.
The shuttle was a combined civilian-military project from the start - intended as a cost-saving measure (and/or to suck in military money to make the project possible). So it was designed to handle both civilian and military missions. Civilian missions typically involve near-equatorial orbits (science platforms, synchronous-orbit comsat plus low-to-high-orbit booster, etc.) These launch to the east (mainly from Cape Canaveral) to get an initial boost from the Earth's rotation. Military missions have a higher proportion of polar orbits (such as observation satellites - where one can see the whole globe because the Earth turns under it.) Polar orbits get no help from the Earth's spin and thus have much less payload for a given amount of vehicle and fuel. Intent was to launch them to the south from Vandenberg.
But the military had another mission in mind, back in the cold-war days, which got designed in. This was a fractional-orbit "pop-up" scouting (or something...) polar mission: Launch south (or potentially north, though this takes you over land in case of trouble), once-around getting your pix (or doing whatever), and land after one orbit. Ideally you'd land the same place you launched from (i.e. Vandenberg) so you can immediately recycle the craft, rather than having to mount it on a 747 to ferry it from the landing to the launch site. But the Earth turns under you while you're in orbit. A "normal" mission can just multi-orbit for one or more half-days until the launch site is under the track again. But on a war footing you can't wait a half-day: a) you might get shot down (losing the info and/or the scarce military resource) and b) your info is delayed. So a one-orbit pop-up mission means you need a lot of cross-track aerodynamic capacity: Come down to where you're out of braking and into gliding mode, then turn east and chase down the landing site. To handle this mission the shuttle was given those much bigger wings.
There's a stock ratio for rule-of-thumb ratio for computing a low-earth-orbit vehicle's polar payload as a fraction of its near-equitorial payload. Story goes this was applied to the Shuttle in the early design phases and it came out with a decent number even with the big wings. But the problem is that it was applied to "payload" as in "payload bay capacity". In the case of the shuttle THE ORBITER IS ALSO PAYLOAD. With the bigger wings it can still do a polar flight - but after deducting the orbiter, crew, and consumables you end up with a payload of a couple hundred pounds. And this was figured out too late in the design phase to rehack it.
So the military got their pop-up mission - but lost the ability to do polar satellite launches. After this was discovered they abandoned the construction of shuttles for the Vandenberg base, mostly bailed out of the shuttle program, and did their own regular-booster satellite launches. The Vandenberg shuttle-launch facility was mothballed (except as a backup landing site) and the Shuttle was always launched from Canaveral.
Now maybe it wasn't really a mistake. Maybe they were intending to use one of the intended followon replacements for the boosters/tank combo that might have given them nontrivial polar capacity - and finances never materialized. But the net result is that the shuttle has too-big wings,thus way-expensive launches, thus didn't do all that many launches, thus never developed the economy-of-scale that would have brought the price down SOMEWHAT (though never to where it would have been with dinky wings.)
Bummer!
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
The shuttle landed safely.