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Skydiving from 25 Miles Up
chisox writes "The Observer has a story about a retired French army colonel who is soon to make a free fall parachute jump from 25 miles up. In the process he will break the sound barrier, reaching a top speed of mach 1.68 before he opens his parachute 1,000 metres above the Earth. Of course, if the chute doesn't open, the hole he'll make will be about 1,000 metres deep." Well, actually his max speed will be high up and near the earth the atmosphere will have slowed him down to terminal velocity.
I don't think his ears will be in the area which could experience the sonic boom. The sonic boom is actually a cone-shaped are where the sound becomes concentrated (because you are moving faster than it).
I am more interested in how much his suit would heat up if his chute doesn't open due to air resistance and decreasing terminal velocity.`
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Well, actually his max speed will be high up and near the earth the atmosphere will have slowed him down to terminal velocity.
Well, actually he'll be at terminal velocity for nearly the entire time... Terminal velocity is dependant on the density of the atmosphere. You'd think that someone that posted a link to a page which defined "terminal velopcity" would have at least read the definition...
Nope. Won't be any sonic boom. He'll break the sea level speed of sound high in the atmosphere, where the speed of sound is higher. As he descends, he'll slow to terminal velocity. So there will never be a shockwave.
"Of all days, the day on which one has not laughed is the most surely the one wasted." -Sebastian Roch Nicol
Someone should tip off the drilling companies: rather than pay skilled people to operate fancy drilling rigs, just drop the rigs and/or people out of an airplane.
Nope, not at all. Terminal velocity is the max velocity you can travel at a certain point in the atmosphere. You hit it really quickly. By the time he pulls his shoot he won't be travelling any faster than someone who jumped from 15000ft. He'll be going fast when hes REALLY high up and the atmostphere is thin and terminal velocity is higher.
"Of all days, the day on which one has not laughed is the most surely the one wasted." -Sebastian Roch Nicol
"it does make you wonder why something like this has not been undertaken by any government agency."
y di vin.shtml
/. injects a space in that URL.
This has been done. I'm not sure why we forget. In 1960, Joe Kittenger jumped from ~20 miles, breaking the sound barrier. See:
http://www.dropzone.com/news/SpaceParachutingSk
A.
ps: I'm sorry that
...bringing you cynical quips since 1998
my IIS is also in the serverroom, on a CD which makes sure the table stays stable and horizontal..
:-)
Sorry, couldn't resist..
Nobody expects the spanish inquisition!
ISTR that the speed of sound changes with air pressure and it's faster when the pressure is lower. The speed of sound at sea level is around 300 m/sec so mach 1.68 at sea level would be around 500 m/sec.
But at 100,000 feet, the speed of sound in that thin air might be 1000 m/sec. So if the guy is falling at 500 m/sec at that altitude, that's really just half the speed of sound there. If he's falling at 1700 m/sec, that sounds awful, sonic booms and all that kind of thing.
So what's the deal?
(* Of course, if the chute doesn't open, the hole he'll make will be about 1,000 metres deep." *)
I hope he does it near my hometown. I always wanted to visit that crater in Arizona, but it is too far and too hot.
We need a local one.
Table-ized A.I.
http://www2.tsixroads.com/Corinth_MLSANDY/jk004
including an amazing shot of him taken from the gondola from which he jumped:
http://www2.tsixroads.com/Corinth_MLSANDY/corin
I use Friend/Foe + mod-point modifiers as a karma/reputation system.
(* Will he really experience a sonic boom? If so wouldn't that destroy his ear drums. *)
Do French sonic booms sound more romantic to chicks than American sonic booms?
Table-ized A.I.
Nobody is obligated to do with their money what YOU feel is the best thing. How many of the qualities of life you take for granted today would not exist if someone hadn't "wasted" a lot of time, money, and effort on things that have "no relevance"?
I personally have no desire to float 25 miles up into the atmosphere in temperatures over a hundred degrees below freezing just so I can fall faster than the speed of sound. But if this guy wants to do it, more power to him. As long as SOMEONE is reaching higher for what nobody in their right mind would ever want to do, the rest of the world will benefit as a result, even if indirectly.
I'm not saying that funding medical research is bad. Its just as noble an endevour as any other. But to say that other reasearch does no good for the world simply because the immediate results do not, is very short sighted and reeks very badly of the "everything's already been invented" mentality. And besides, consider the fact that since he has partially funded this effort of his, the experiments he's carrying out will benefit agencies that otherwise would have to spend their own money to carry out similar experiments anyway. That means that money will be saved.. which means it might be available elsewhere, including your own personal preferred pet projects. And that's just looking at things from an immediate economic point of view.
-Restil
Play with my webcams and lights here
65 million years ago, the dinosaurs disappeared mysteriously from the earth, supposedly caused by an impact from a meteor or piece of comet.
A.D.2002: A retired French army colonel makes his skydive from 25 miles up. As he approaches mach 1.68, a bright flash is seen, and he vanishes. For years, the mystery of what happened to him remains unsolved.
A.D.2042: It is discovered that at the moment the retired colonel reached mach 1.68, he caused a rift in the space-time continuum and travelled 65 million years back in time and slammed into the earth at 1200MPH, creator a crator and wiping out dinosaur life.
According to the Worst-Case Scenario Survival Handbook (http://www.worstcasescenarios.com) if you plan to jump from anything high you should be prepared to at least break your legs, and clench your buttocks as you go down so as to keep water from rushing in and um, causing severe "internal" damage. Jumping from over 50 feet is ill-advised as it will almost certainaly break something other than your legs (spine) unless you hit at exactly the right angle. At 120 MPH you may not be able to adjust yourself by the time you realize that you're going to enter at a slight angle thanks to that last second cross breeze.
Interestingly though, according to the same book you can probably survive a 50 foot fall into a dumpster of boxes with few complications.
Will he really experience a sonic boom? If so wouldn't that destroy his ear drums.
Actually, no. The sonic boom is never heard by the body traveling at supersonic speeds, wether it be plane, rocket, or person. Concorde passengers are unaffected by the boom.
The conical shock waves never touch. At least they aren't supposed to. Now, since a person is thin like a rocket, I am sure he won't have to worry about shock waves.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
"So I look at something like this and go how will this advance mankind. The only answer is that it will not. This is like trying to balloon around the world. I think subjuects like this have no0 relevence on slashdot. He could take the money that he is squandering on this and give it to doctors without borders and actually do some good in this world. Isn't it time that postmodernism died."
You know what the moral difference is between robbing someone on the street at gunpoint, and using your government representatives to do it for you?
None.
What you state is VERY contrary to the spirit of freedom and individual liberty. What someone does with his own time and money is no business of yours at all.
How about your own life? That money you spent on that new RAM upgrade could have gone to help AIDS victims. That money you blew on beer and pr0n magazines could have gone to help the homeless.
See what I mean? This is, in essence, what socialism is: A central comitte decides what is done with money, property, and individuals, NOT the individuals.
I don't think that is what you are advocating, at least, I hope not...
If not for the individual freedom the USA is supposed to stand for, and the incredible spirit of adventure and creativity this spawns, the world wouldn't have had:
Charles Lindburgh
Wilbur and Orville Wright
Who both did things that were thought to be nutty at the time.
There is a reason why most great inventions of the past 150 years have happened in America. One word: Freedom.
Freedom to do with what is yours, and what gifts you have, as you will.
Corporatism != Free Market
check out his home page:
e s/ gb_accueil.html
http://www.legrandsaut.org/
or straight to the english version:
http://www.legrandsaut.org/ressources/gb/gb_pag
He has some movies and facts and explanations and interviews....etc
few on land.
Well...He may get to hold the record for highest skydive but *I* hold the record for parachuting night pukes.
No one has gotten sick jumping out of an airplane at night as many times as I have.
I keep waiting for someone to try to break my record. They are all afraid to try!
See it here: http://AICommand.com/PukeDuke.htm
Guru312
Just because several (I know of at least half a dozen) sites have that sound-barrier quote, that doesn't make it true.
;)
I consider the several links on that page as a good cross-section of sources, and from what I read, I agree with Kittenger himself that the most reliable information is that he achieved 90% of the speed of sound at his altitude. The most credible information was that his top speed was 614mph, and that somebody somewhere made a typo of 714, hence many sources believed he broke the speed of sound. It turned into one of those urban myths. There was no evidence at all that he broke the sound barrier, and reasonably solid data that he didn't, and the man himself agreed with the 614mph data. Also, the math agrees with this, showing that another 1300m or so of altitude is needed to break the sound barrier.
It's not like everybody was out there with their own altitude radar taking measurements. I'll side with Kittenger's own opinion, that the radar reading was the most reliable, and that the man himself is more likely to be correct than a few sensationalist storytellers.
So when the data and the people involved say he didn't break the sound barrier, I'd say that's the closest to definitive that we have.
Disclaimer: No, I don't believe anything simply because it's posted on a website. But I remain happy to disagree with you. Enjoy!
I like this picture better.
Bleh!
GE once designed a device called the MOOSE, to allow astronauts to bail out from orbit and re-enter the Earth's atmosphere with little more than a space suit and plastic cocoon (remember that early heat shields where basically a big slab of high-temperature plastic that would flake off during re-entry).Here's one link about the MOOSE: http://www.boggsspace.com/strange_but_true.htm
It's a good story so I don't want to Lone Gunman it. Suffice it to say, no one gets killed and those involved weren't QUITE that stupid. There is a true story that gave birth to the urban legend. What REALLY happened isn't quite like the parent quoted Legend.
. ht ml
http://www.wagoneers.com/pages/RocketCar/rockit
Going down isn't the problem. If the shuttle were geosynchronous, no problem.. if you had space suit, you could make the jump no problem (well, very little problem)..
But the shuttle is also moving around the earth VERY quickly.. something like 17,000 kph (feel free to correct me), which would kill you pretty much instantly when you encountered the atmosphere, and had to slow down your sideways speed.
Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
Since he will break the sound barrier and eventually start to slow down, he could sing a close harmony duet with himself.
Cool.
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