Tiangong - 1 Chinese Space station expected to come down near Corsica

[Marty_d]

Or send a big powerful magnate up, It should grow with all the Attachment's adorning it.spacesailor

If it's the magnate I'm thinking of, can we send him up without a space suit?

 

 

[Phil Perry]

."Could land on our National Parliament, tsk, tsk!"Do we send the Chinese a bill for damage, or a medal.

 

" Lots of research is being done on snagging or shooting down space junk with lasers;"

 

Or send a big powerful magnate up, It should grow with all the Attachment's adorning it.

 

spacesailor

Oh , , ,errr. . .I didn't know that magnates had any effect on Alooooominum cobber. . . . .

 

 

[Phil Perry]

There's only been one recorded hit on a human from space debris in all of history, a woman who ended up with a huge black bruise on her leg.My Mum got hit by the nut of a slasher blade bolt when the blade came off (and whizzed past her head) and left a huge black bruise on her leg, and I have been hit in the eye by debris from a whipper snipper.

So I am infinitely more concerned about someone mowing near me than I am about a satellite re-entry.

One of my Polar Involved mates said a few years back that one of his antennas at a Polar research station ( North) was damaged by a meteorite. . .. he reckoned that you could find them easily in the permafrost due to their blackened colour. . . .

 

 

[spacesailor]

Never seen or ever will see an "Alooooominun" Nuclear reactor, as most space craft are powered by them.

 

Once up in space, weight of Titanium or steel & lead & gold wrapping is irreverent (spelling). Could even take your Old car up for a space-run. LoL

 

spacesailor

 

 

[Admin]

I would have thought that weight would have an impact i.e. whether it is made with Lead or etc. The satellite is in orbit because of gravity although gravity becomes more and more less the higher you go so a heavier satellite would need to be in a higher orbit if it is to maintain an orbit and not come back to Earth. I could be wrong as its been 40 years since I did physics.

 

One thing I am curious about is those satellites that are for military or intelligence are constantly being repositioned. The only way I know of to reposition a satellite is to use thrusters so where is the petrol station up there to refuel these things?

 

 

[pmccarthy]

If you fire thrusters in the direction of orbit you increase the orbital velocity and the satellite moves further from earth. And vice versa. That’s why the movie Gravity was BS. They just saw a target and fired thrusters toward it. Doesn’t work that way.

 

 

[Old Koreelah]

Never seen or ever will see an "Alooooominun" Nuclear reactor, as most space craft are powered by them...

I doubt that, Spacey. Deep space probes like the Voyager, which travel far from the sun, certainly depend on nuclear power, but I believe most earth-orbit satellites get enough power from solar panels.

 

 

[spacesailor]

Velocity keeps satellites from falling back to earth, when the velocity decays they return back towards their origin, unless gravity is stronger from another source.

 

The Chinees one has run out of power to increase its velocity, hence its return trip.

 

spacesailor

 

 

[Birdseye]

Velocity keeps satellites from falling back to earth, when the velocity decays they return back towards their origin, unless gravity is stronger from another source.The Chinees one has run out of power to increase its velocity, hence its return trip.spacesailor

Incorrect according to my understanding; it is not a fuel/power issue, but a control one. They are unable to command a burn, hence the reason its returning to earth uncontrolled.

 

 

[Soleair]

Velocity keeps satellites from falling back to earth, when the velocity decays they return back towards their origin, unless gravity is stronger from another source.The Chinees one has run out of power to increase its velocity, hence its return trip.spacesailor

I believe the principle of conservation of energy means that any object in orbit will continue at its present speed almost indefinitely. It takes energy to slow it down, not maintain its current velocity. The only force slowing any satellite in orbit outside our atmosphere is collision with either space junk; interstellar dust; the odd stray molecule of gas that's lost its way, or solar wind - but they're all relatively small forces.

Consider the earth's original satellite, the moon. It has been orbiting at very close to its present height for quite a while now, without the benefit of thrusters.

 

Bruce

 

 

[Old Koreelah]

All true. I believe the main cause of orbit decay is friction with our planet's thin upper atmosphere, which expands and contracts enormously. It can extend far into the orbital zone of some satellites.

 

Very well illustrated in the Sanda Bullock movie.

 

 

[bexrbetter]

I am less worried now that the BBC have just reported that Tiangong "may" hit Earth, clearly there's a chance it might miss then.

 

the Moon has been orbiting Earth without the benefit of thrusters.

You obviously don't read some of the websites I read ....

Also I was just thinking, if it lands in America, I wonder what the tariffs will be?

 

 

[Birdseye]

Shhhhh! You'll frighten the Chinese by mentioning tariffs.

 

 

[Phil Perry]

Velocity keeps satellites from falling back to earth, when the velocity decays they return back towards their origin, unless gravity is stronger from another source.The Chinees one has run out of power to increase its velocity, hence its return trip.spacesailor

satellites and similar vehicles have small thruster units which are used to maintain angular geometry. The ONLY way to maintain orbital velocity and prevent decay is a bloody great rocket burn to increase the speed of the vehicle and therefore maintain orbital momentum. Otherwise,. . .the string with which you are swinging the bucket of water around your head goes a bit slack,. . .and the bucket falls to the ground. . . HOWEVER .. . .since the satellte vehicle has been spewed out of it's launch vehicle,. . .the bit wth the rocket motor in it,. . .this is not possible. So All satellites have a very finite 'Orbital Life' before their orbits will decay to the point where they have to begin their descent back to Mother Earth. Maybe the Chinese ought to have bolted a rocket motor on to the thing to give an orbital burn ? ?

I would have thought that blokes like Elon Musk should have thought about ths, since the shuttle programme was ended,. . .to sort a vehicle which could rescue expensive satellites and return them for refurb. . . .? Over to you Elon. . . .

 

 

[bexrbetter]

Just booked tickets to Hong Kong and back on the weekend (business), right in the prime time and area for it to take out a plane ....

 

Mind you, probably a Chinese airline so I was already taking a chance ...

 

 

[facthunter]

Significantly large lumps could land anywhere. They really have NO idea where this one will go. Just bad luck if you are under it. There's so much junk up there it's a real threat to space travel and it will all come down some day. That's the way it works as it slows down over time. Nev

 

 

[w3stie]

They burn the thrusters on the ISS from time to time to keep it up there. Here's a demo of what happens when they do.

 

 

 

[Phil Perry]

Just booked tickets to Hong Kong and back on the weekend (business), right in the prime time and area for it to take out a plane ....Mind you, probably a Chinese airline so I was already taking a chance ...

Well,. . .if your plane takes a hit mate,. . .I'd like to say that it's been nice to know you. . . . . . tell the Missus too,. . . you're a popular bloke here and it was nice to have you on the forum. . . . .

 

 

[Guest Guest]

Just booked tickets to Hong Kong and back on the weekend (business), right in the prime time and area for it to take out a plane ....Mind you, probably a Chinese airline so I was already taking a chance ...

Good luck, not from the space junk as that would be Yuneec to say the least more the Chinese Airline! -:)

[bexrbetter]

Well,. . .if your plane takes a hit mate,. . .I'd like to say that it's been nice to know you. . . . . . tell the Missus too,. . . you're a popular bloke here and it was nice to have you on the forum. . . . .

Thanks Mate, going to change my Will tomorrow to include you, just in case.

I'm leaving you my pristine VN Commodore with only 420,000 kms. The undercoat hides the rust very well and you'll only need 4 wheels to get it onto a trailer, you can keep the bricks. Pick up anytime from Logan City, easy to spot out in the street. Ignore the Council notices.

 

 

[bexrbetter]

I made it, in Shenzen and still alive!

 

I actually went to Zhuhai and caught the ferry to Shenzen to look at the Zhuhai to Hong Kong bridge, holy mother of dog, it is surreal, it's a bizzarely long bridge sitting out in the middle of the sea, utterly out of place.

 

Google pictures of it, but they don't come close to seeing it for real.

 

Go to China not just to see the Great Wall, but now also the Great Bridge.

 

 

[Marty_d]

That's an impressive project - 50km all up according to Mr Google (3 spans plus undersea tunnel).

 

 

[Birdseye]

The demise is getting close, perigee at 0303Z today was 161.6km, now in the region where decay will accelerate rapidly.

 

A nice live graphic on www.heavens-above.com if anyone wants to follow it.

 

 

[facthunter]

Just passing over northern NSW coast. Stopped losing height and mild increase. The plot is incorrectly recording the latitude as NORTH.(Finger trouble on the site?) NSW coast to NZ in three minutes. Entry at height of approx. 100 Kms. Way to go yet. Recovered 6 kms and still climbing at 2.49 EST. Nev

 

 

[Birdseye]

Apogee was 179.7, but by the next perigee it had lost 0.5 km at 161.1