ST401385@BROWNVM.BITNET (02/05/86)
A friend (Michael Bishop) recently asked me whether a butterfly
would be able to fly in zero-gee.
QUESTIONS:
(1) Does anyone have any good ideas on the subject?
(2) I recall that one of the shuttle flights had an experiment
involving fruit-flies. Did anybody look at them to see if they had
any trouble flying? Does anybody know where I could find the results
of the experiment? Does anybody know of any other experiments with
flying insects in zero-gee? (I seem to vaguely recall an experiment
involving bees?
DISCUSSION
In general, flying involves a continuous interaction between
lift and gravity. In ZG, you'd have to fly at zero lift, or else
do nothing but loops. And, of course, you can't truly glide in
ZG: in a glide the energy you lose to drag is taken out of the gravitational
potential energy, nonexistant in orbit.
On the one hand, butterflies aren't very bright. Their flight behaviour
is probably hardwired into their little brains, and they thus probably
aren't very adaptable. On the other hand, butterflies are very small.
They fly at tiny Reynold's numbers (probably in the single digits,
although I haven't done the calculation) where viscous drag is large,
and further, they have low weight. Thus, I would expect that gravity,
rather than being a major force in their lives, is more a second order
perturbation to them. And they are smart enough to adapt to various wind
conditions, etc. So my guess is that they probably could fly, although
they might have some problems, resulting in missed landings, etc.
Geoffrey A. Landis
-------Special note to Bob: I can't reach you on the net. Apparently
the mailing exec here automatically capitalizes all addresses. Why
don't you find a host that recognizes its name when written in all CAPS??