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Sophisticated Balloons Could Help Steer Spacecraft
coondoggie writes "Getting spacecraft traveling at hypersonic speeds to slow down and land or achieve a particular orbit on a dime is no easy feat.
But researchers are developing a tool that will let engineers model and ultimately build advanced flight control systems that meld balloon and parachute technologies known as a ballute (BALLoon-parachUTE). Basically a ballute is a large, inflatable device that takes advantage of atmospheric drag to decelerate and capture a spacecraft into orbit around a planet, according to NASA who is funding Global Aerospace to build such a tool."
This would be a very efficient way to put a satellite into a nice, 100 mile high orbit. DOH! 100 kilometers! WHATEVER!
I just hope that the life of NASA folks is not becoming obsessively balloonic.
Ezekiel 23:20
The word (warning, link not for PETA or squeemish) balut is pronounced baloot too.
OK, this idea's been around for awhile. Its major useage in Hollywood was in the movie 2010 when the Russian spacecraft used one for aerobraking in Jupiter's atmosphere. Cute effect, but like Dr Floyd said, "Nice in theory, but the guys who did the numbers aren't here."
Understanding the scope of the problem is the first step on the path to true panic.
Atmospheric drag? It sure is going to be cool when they come out with a big balloon, covered in multi-inch thick ceramic tiles for heat dispersion.
Slow Down, Cowboy! It's been 60 minutes since you last successfully posted a comment.
I seem to remember 2010 Space Odyssey using what they called in the movie a ballute to slow down on arrival at Jupiter.
advanced flight control systems that meld balloon and parachute technologies known as a ballute (BALLoon-parachUTE).
I'd have called it Paraloon.
Or possibly Ballachute.
"Ballachute! I choose you!"
Yep. It works.
North Korea is developing long range "Communications Darts". These are not in any way intended for use as weapons.
Let's say they did open more names to write-ins and respect all submissions. Do you really want everything to be named Colbert?
Future News: "The Colbert shuttle docked at Space Station Colbert earlier today after leaving Lunar Colony Colbert 1. After refitting for supplies, it will re-land on Lunar Colony Colbert 2 tomorrow."
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
I officially think that the folks at NASA are a bunch of jerks for not respecting the results of their ISS node naming contest. :-(
Indeed.
It kills our best chance of making our first contact with a ship called "Skullfuck Soulshitter".
Your NASA Tau Chi name is...Ballute.
My Filipino heritage is screaming in agony of trying to eat something not fit to be eaten.
We are the Borg...
I thought that was that NASTY Filipino snack food consisting of a cooked, fertile duck egg with a pinch of salt...
Buzzing the information Superhighway at Warp speed
My other car is a ballute.
Oh yeah? well my new cadillac is a ballute de ville.
yo momma's so fat, when she jumps out of an airplane, she has to use a ballute.
I would write more, but my computer's about to crash, so I have to reballute.
stuff |
I have no problem if they don't want to have write-ins. What I have a problem with is when they offer the write-in and then don't respect the results. In business, they call this bait-and-switch. It demonstrates a lot of arrogance.
If you don't want crime to pay, let the government run it.
Oh it is, is it Mr AC?
The key problem with atmospheric braking is heat dissipation. Craft in orbit have considerable energy (since they have orbital velocities of around 7.5 km/s or more) while craft returning from the Moon or Mars have far greater velocities (the Apollo capsules returning from the Moon had velocity of roughly 11 km/s, which is double the kinetic energy per kilogram of a low Earth orbit satellite). Entering orbit around a gas giant (like Neptune) will require even velocity dissipation. If you and everything on your spacecraft were indestructable, you could just dive straight in. In practice, since spacecraft aren't indestructible and payloads (eg, living humans) are somewhat fragile, you need to decelerate at a much more gradual pace. As it turns out, the sooner you can start deceleration, the better. The key way to decelerate early is to increase the cross-section area of the vehicle relative to its mass. This also has the advantage of distributing the heat load from atmospheric braking across a wider area and reduces the overall temperature of the vehicle. This reduces the complexity of the structures used to protect the vehicle from atmospheric heating (called "thermal protection systems" or TPS).
Capsules like Soyuz or Apollo have the highest mass per cross-section area and hence have high heating loads and decelerations. The Shuttle has pretty high heating loads as well. If it had been made considerably "fluffier", it wouldn't need the special tiles for its TPS.
Ballutes are cheap ways to greatly increase the cross-sectional area of the vehicle. For a fictional example of a ballute, the film 2010 portrays the Soviet spaceship, Leonov using one as it aerobrakes to slow down enough to orbit around Jupiter. Technically, in this case, it is aerocapture. This is aerobraking with only one pass through atmosphere. The usual process involves many passes through atmosphere, shedding some velocity on each pass.
The innovation in this article is the ability to control a ballute which has some lift. There are two possible uses that I can think of, off the top of my head. First, it can be used to steer the vehicle so that more of its path is in the less dense high atmosphere. In other words, we can steer to some degree the trajectory so that we get better deceleration and heating loads. Second, aerocapture is very hard. The key problem is that any changes in the atmosphere will change the trajectory, possibly enough to make the attempt unsurvivable. Even if the vehicle isn't in danger, small differences in the atmosphere or the vehicle's reentry trajectory mean the vehicle may end up on a different trajectory. If it is landing, it may end up far away from the desired landing spot. Ability to steer reduces the uncertainty of aerocapture and provides some valuable margin of error for a spacecraft.
I stand corrected. I didn't know that word, and apparently had too much faith in my english skills to look it up in a dictionary.
steer my eyes straight to their racks.
True. Many times space engineers are inspired by SCi-Fi authors. Don't forget, many of those authors have had scientific and engineering training. Heinlein had a few degrees in that area- IIRC.
In other news, Al Gore is starting a pre-emptive campaign against "Air Ballution". Pundits are already sharpening their witty one-liners.
You wipper snappers! In my day, everything had to be named Enterprise - and we liked it!
This article is a real let-down (pun intended). When I saw the title in my RSS feed, I was expecting to read about some novel idea to use balloons to steer a craft in the vacuum of space. Using things like balloons and parachutes to slow things down in the atmosphere is not a novel idea.
filipinos laugh at the unintended linguistic joke
balut
althoug, using the word for something that is half-duck half-egg, is a pretty good metaphor for this polymorphous device
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Certainly, you've heard of a vulcan mind meld before? If not, get off my lawn!
Nope - you must be thinking of someone else. Heinlein was a graduate of the Naval Academy and a dropout from UCLA.
Isn't this only useful if you want to orbit a planet with an atmosphere that won't destroy the ballute?
/. so please feel free to jump in and clarify - I'd really like to understand.
And question #2, if you're in the planet's atmosphere you're no longer in orbit - right?
There are tons of space nerds on
I'm a 2000 man.
Our favorite part of ballute aerobraking is when the beautiful Russian heroine comes into your state room & starts making love to you.
After a long conference and much discussion, it was decided not to use the other alternative, unsophisticated balloons.
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Sophisticated Baboons Could Help Steer Spacecraft
Well, I think their intent was to honor legitimate submissions, not become the punchline for a comedian.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
I can't speak as to what they'd use to fill it, though air seems like a more obvious choice than liquid helium. And even if the gas was lighter-than-air the entire assembly is not necessary light enough to be buoyant, particularly at high altitudes.
Regardless, even if the ballute were buoyant and durable enough to stay high in the atmosphere for significant periods there is a trivial solution -- open the gas chamber when the ballute is released.
Perhaps that why they featured, quite prominently, a big disclaimer saying they were not bound by the results?
Perhaps they wanted a glimpse into what the public thought, rather than opening it up to ballot stuffers and vote riggers?
Maybe, just maybe, they had the idea that giving people a voice was not quite the same thing as giving people the final say?
The Russians did do this or will do this in 2010. It's called aero-braking. Just don't attempt any landings on Io.
I'm a BBS orphan in a blogging world.
"... spacecraft traveling at hypersonic speeds..."
I'll bite, what is the speed of sound in the regions in which he ballutes will be used? Doesn't it depend on both pressure and temperature? Are the SiFi movies right and there is sound in space after all?
Nate
that Ballute is also the asian word for an egg with a dead fetus inside it (yes, to eat).
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Esobofh - Currently drinking fresh mango juice.
I like the idea of humans making contact with aliens and both ships having stupid names due to internet tricksters. That would be a sign that things are going to turn out just fine.
Of course the the alien ship is called something like The Dear Leader, then we've probably got a problem on our hands. Either that or those green bastards on the alien equivalent of 4chan have a sick sense of humour.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
Look at the cover of Popular Science, October 1983. Note: I used to work with Dr. Dana Andrews, at Boeing, in the early 80's. We were working on such things back then. Dana was the consultant for the movie 2010. We had fun going to see the movie as a group, and making critiques:
"Hey, that's a subsonic wake, that's wrong"
Aerobraking is a subset of hypersonic aerodynamics. Inflatable things like Ballutes are zero lift pure drag devices. You can also control direction if you use a lifting body shape. if you fly nozzle-first and shoot some cold fuel out, you can use it for a cool film and protect everything from melting.