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Video shot from the Space Shuttle during launch

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Re: Video shot from the Space Shuttle during launch

#22
post #3

I'm surprised they landed so close together. amazing. Also, can anyone tell me why they are slowing down as they fall towards earth (before the parachutes deploy)? Shouldn't they be speeding up by 9.8m/s as they fall?

> I'm surprised they landed so close together.

this doesnt make sense to me. On the orbit they look like they gaining a distance between each other. Any distance on that altitude would be 150-fold back on earth. How come they landed less than 20m from each other, no idea. Anyone?

Re: Video shot from the Space Shuttle during launch

#23
post #10
post #2

Startup idea: put me into space. For cheap.

You probably only get the "For cheap." requirement fullfilled if you also leave out the so-far out-of-spec "and get me back again alive" requirement…

I hear what you saying, but is there anything else than an issue of material being burnt in atmosphere due to speed lost/air friction? Gravity will make sure you will get back on Earth so its not like you have to spend another million bucks to get on earth. Given you have a heat/damage-proof can and know when to open parachutes (I know its more complicated than that), you should be good to go (I mean - come back).

Re: Video shot from the Space Shuttle during launch

#24
Can someone explain what the nominal "velocity" counter means? I thought it made sense going up (although I wasn't sure why its rate of change---which would be the acceleration---seemed to increase a bit), but then I was totally baffled after the separation. It goes down from 2900 to 2500, then back up to 2920, then it plummets to around 300, then gently lowers down to the 50 or so that it's at for splashdown; there is no discernible change in acceleration when the chutes blow around 190.

Here's what I would have expected: numbers increasing at a relatively constant rate until separation, then a rapid decrease to zero (and since 1mph ~~ .5m/s, expected decrease at about 20mph/s), then increasing again (maybe with a negative sign) until atmosphere, then a decrease to terminal velocity, then another big decrease when the chutes blow.

So aside from the fact that there is no direction (not even a minus sign), so it's at best a speed counter, there still is something I really don't understand about that number. But... what?

(Edit: fixed dumb math error)

Re: Video shot from the Space Shuttle during launch

#25
post #3

I'm surprised they landed so close together. amazing. Also, can anyone tell me why they are slowing down as they fall towards earth (before the parachutes deploy)? Shouldn't they be speeding up by 9.8m/s as they fall?

they should be speeding up but not until infinity of course. At some point (here around 300mph) their size with "glide" in the atmosphere causing it to slow down.

It was interesting to watch how they gained speed on the orbit while being sucked by Earth gravity, and then quickly hit the breaks when atmosphere/air got thicker... awesome! Must be amazing feeling, given you would have 3000mph-withstand material, to actually "drop" yourself from space to Earth :)

Re: Video shot from the Space Shuttle during launch

#26
post #2

Startup idea: put me into space. For cheap.

This will happen. One of the reasons the Concorde never really succeeded was due to the nature of faster than sound travel. A sonic boom doesn't just happen as you pass the sound barrier, but rather trails behind an aircraft the entire time it is traveling over that critical speed. This resulted in the Concorde only being able to travel faster than the speed of sound when it was over water (hence it's primary use for…

One of the other reasons Concorde never really succeeded was due to the other part of the nature of faster than sound travel: it uses a huge amount of fuel, which is a major expense. For comparison, the 747-100 (which made its first flight just before Concorde's) used perhaps 1.1 times more fuel to cross the Atlantic but carried about 4 times as many passengers.

Suborbital space flight means any place on the globe is a 2 hour flight away, but the fuel costs are pretty high. I expect such a service to one day exist, but I don't expect to be able to afford it.

Re: Video shot from the Space Shuttle during launch

#27
post #2

Startup idea: put me into space. For cheap.

This is an appropriate place as any. WE have an ambitious start up idea to launch loaves of bread into space so that they will re-enter as toast, perfectly cooked to perfection and delivered right to your door.

Re: Video shot from the Space Shuttle during launch

#28
post #3

I'm surprised they landed so close together. amazing. Also, can anyone tell me why they are slowing down as they fall towards earth (before the parachutes deploy)? Shouldn't they be speeding up by 9.8m/s as they fall?

> I'm surprised they landed so close together. this doesnt make sense to me. On the orbit they look like they gaining a distance between each other. Any distance on that altitude would be 150-fold back on earth. How come they landed less than 20m from each other, no idea. Anyone?

Where do you get the figure of 150? I reason that if they are nearly identical pieces, and falling near each other, wind and other atmospheric forces would shift them about equivalently. Even if they veered hundreds of miles, it seems reasonable that they would do so together.

Re: Video shot from the Space Shuttle during launch

#30
post #2

Startup idea: put me into space. For cheap.

This is an appropriate place as any. WE have an ambitious start up idea to launch loaves of bread into space so that they will re-enter as toast, perfectly cooked to perfection and delivered right to your door.

I won't invest until you demonstrate your solution to the fundamental physical principle that causes it to land butter side down.
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