Japanese Scientists, Origami Masters Hope to Launch Paper Airplane From Space
Right up until you read that there is no way to prove a damn thing because they can’t track it.
Oh.
Well why the hell didn’t you just take the money and go find the best sushi house in the country and invite the neighborhood? I’d show up for that! Talk about literally throwing money away. That better be some damn fine origami paper.
Feeling a tad cynical today. Lotsa reasons, no simple answer. So enjoy a home-grown demotivator. Click it and it’ll open larger (approx 450kb).
More on Hil Clinton from Dick Morris… man is she ever scary. If I had to choose between her and eating broken glass I’d first ask if I could have ketchup with my meal. Knowing how to speak is good, as long as you know when to shut up.
Last, another Modern Mechanix: Dangerous Acids Made Safely by the Home Chemist.
Fun for the whole family. Warning kids, do not experiment on each other. The cat will work just as well.
[Note: Lemur King's Folly does NOT endorse the use of acids on felines, so chill out.]
I’ve always wondered why re-entry speeds lways have to be blisteringly fast. I understand that anything at orbital velocity is zipping along and that has something (if not everything) to do with it, but it seems like there should be something they could do to to slow down and just ease into the atmosphere. Whelp, I guess if they could they probably would already be doing that. McGoo could probably explain.
If I read the article right, they are thinking about launching a bunch of the things and then seeing where they land via people picking them up and finding a number to call to let researchers know where and when they were found. It could be interesting.
Well, one part of it is that by definition to reach orbit you are going to need escape velocity – 16,000mph (that’s a gross simplification). You’re going pretty fast, and you have a certain angular momentum as you orbit the Earth.
You’ve seen what happens when a skater brings his/her arms in close, they start spinning faster. If you bring your arms in, your moment of inertia decreases and since angular momentum is conserved (barring outside forces, and air resistance is pretty small in this case) the angular velocity goes up.
Looked at another way, consider the gravitational potential energy between two bodies where at least one is big enough to exert a noticeable gravitational force – the object will start moving and as it undergoes a steadily increasing gravitational acceleration, it’ll go faster and faster. Of course that’s assuming no atmosphere to slow you down (terminal velocity).
I’m fried from a long hard week, and I have not put it as clearly as I should in terms of physics, but I hope that helps somewhat.
You’re right though, if you chose to, you could certainly force a slowdown but that’d take a lot of fuel. Essentially you’d be adding that external force to change your normally-conserved angular momentum. It’d no longer be a closed system.
That’s enough for now. Dinner calls… dead animal flesh on bread… mmmm.
- LK
You explained it perfectly. Thanks! I figured the fuel was probably a big part of it, but when I see video of them in space it looks like they’re just sitting there, and I think “How hard could it be?” Plenty hard, of course
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They look like they’re sitting still but they’re hauling ass in orbit.
Glad that came off coherently. I make stuff that certainly goes into flight and one thingy that went outside earth’s orbit but the nuts and bolts of getting stuff to orbit and beyond is a whole ‘nother ball of wax. Way smarter guys than I ever want to be think up that stuff.
Using planetary gravity assists the spacecraft guys have been jockeying MESSENGER all over the place. Here’s a fun link that shows a real-life example of physics being used to good purposes. The fact that the spacecraft makes six approaches (1 around Earth, 2 around Venus, and 3 around Mercury) to get into an insertion orbit shows how clever the physics guys have to be with the trajectory calculations – there is a huge amount of delta-V required to get to Mercury (conservation of momentum pops up here) and you just cannot carry that much propellant onboard. All that work just to distance yourself from Earth’s orbit. If you didn’t dump the energy somehow you’d be screaming by the time you got there.
http://www.planetary.org/news/2007/0605_Flyby_of_Venus_Speeds_MESSENGER_Onward.html
It would have been better had they launched earlier in the year because the new flight trajectory added two years of travel time. Paranoia requires me to worry about the component lifetime in spite of the fact that it will probably be just fine. You get nervous before a launch or first flight, too (or even a vibe test, really). Really really keyed up.
Especially amazing to me is how little propellant they have actually needed to keep on-course. The trajectory correction maneuvers (TCM) have been very minimal.
Oh, and the other issue they had to think about is that they can’t use the Mercurian atmosphere to aerobrake like they could for Mars missions because there isn’t one.
Anyway. Just three more years to go. (sigh)