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Exploding Water Balloons In Zero G
ArchAngel21x writes "Experimenters burst water balloons in the low-gravity environment produced aboard a NASA DC 9 aircraft. There are 3 videos available in QuickTime or MPEG." From the site: "The tests were conducted in part to develop the ability to rapidly deploy large liquid drops by rupturing an enclosing membrane. As can be seen from the experiment footage, the initial rupture process is nearly ideal, but the finite size of the balloon material eventually ejects a spray from the drop surface. Then, when the balloon material leaves the drop entirely, it causes a large deformation of the drop (blob) which oscillates throughout the remainder of the test. Calculations suggest that such oscillations will continue for hours before the drop eventually becomes spherical."
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Monday, 12 August, 2002 12:22 PM
Have you metaroderated recently?
I just wanted to clarify the parent's comment for those who don't necessarily know what the correct term is.
As someone who has done combustion experiments in the Glenn Research drop towers, I can authoritatively say that the term (that the parent likely means) is microgravity, not zero gravity. Zero gravity would imply that one is defying the rules of physics. Microgravity suggests merely that the effects of gravity are significantly diminished due to free fall: orbit, the vomit comet, or simply dropping a vessel in an evacuated tower.
Things having to do with such experiments are frequently labeled with neat mu-g stickers in NASAs facilities.
-Paul
Three years to forget what a herd of nerds feels like... just in case the server groans, here's the coral caches:
l loon/balloo01.mpg l loon/balloo02.mpg l loon/balloo03.mpg
http://microgravity.grc.nasa.gov.nyud.net:8090/ba
http://microgravity.grc.nasa.gov.nyud.net:8090/ba
http://microgravity.grc.nasa.gov.nyud.net:8090/ba
Regardless of all the sturm und drang you see in Congress over the NASA budget, it's not that big, and has shrunk continuously over the years (in absolute dollars it's about the same size now as 15 years ago when I first worked with them, never mind inflation). They get research planes when everyone else is finished with them. They have a beat to hell F/A-18 that they use for the HARV program, they have the only remaining operational SR-71, and lots of other aircraft that nobody else has use for, but NASA can use for a testbed for something cool.
(I believe that it was just recently expanded, but haven't followed the details)
This is not a low gravity experiment. Technically the best you could call it is a virtual low gravity. The water is actually within the same gravity well as the plane is and is falling to the earth at the same speed. The difference is that it is enclosed in an atmosphere that is also falling at the same speed, or being forced to fall at the same speed. This does not necessarily remove all of the effects of gravity upon the fluid. The results might be similar in a real low gravity environment, but not the same. All this experiment shows is what happens if you fall to the earth at the same speed as the water and air is not whipping around the the water blob to cause deformation. It is important to remember the difference here.
If you are falling into a Black hole and all of the material around you is falling in at the same speed, does that mean you have negated the effects of the Black hole?
Zero gravity cat
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You would expect correct, not popular, terms used on Slashdot...
*ahem*
English is descriptive, not perscriptive.
English is descriptive, not perscriptive.
English is descriptive, not perscriptive.
Our spoken language evolves over time, and words mean no more and no less than how they are used by the greatest number of people.
While the technical or local jargon of certain elements of our culture may include more specific terminology to reflect a desired distinction, this does not in any way invalidate the correctness of the more common term.
"Zero Gravity" as meaning any time when there is no relative gravity is quite enough for most folk. The distinction between no effective gravity due to distance from an overriding mass ("zero G") and there being no effective gravity due to unhindered movement ("free-fall", or "Mu-G") is irrelevant in the common usage.