Hi Doug, Pete and all,
Thanks Doug for the figures you would have to throw at. Looks like our
astronaut isn't going to be launching anything too far out. I appreciate
the figures to back up my claim!!
--AL Mitterling
[EMAIL PROTECTED] wrote:
Al M. wrote:
"I don't think it would be possible for an astronaut to throw an
object, rock or otherwise out of the orbit of the Earth."
Hi Al, Pete, Friends and Listees,
Haven't kept with this thread, but I thought I'd add this info for the
throwing arm of the astronaut to create an artificial meteorite from
some favorite heights.
I noticed Dr. Grossman mentioned the need for extraordinary evidence
(i.e., claims by necessity must be treated with skepicism, until at
least someone can show you a piece of it).
Here are some of the "physics": the minimum speeds the clever
Astronaut would have TO THROW any object to gain an independent orbit
from Earth:
From the International Space station (One of the lowest satellites):
11,412 mph (7,091 Km/h)
From a GPS satellite (nearly the highest):
3,692 mph (5,941 Km/h)
He has to be clever as he needs to throw it exactly in his direction
of motion to make the satellite's speed additive and also away from
the Moon so that doesn't add significant additional speed required. I
just used the 11.2 km/s value at Earth's surface which fails to take
into consideration the air resistance (this is only partly why
expecting material to survive the shear force going up through Earth's
atmosphere is an Extra-ordinary claim). Not a problem - these are the
right answers for space.
The best baseball players on Earth have been clocked at around 100.9 mph.
The best Jai-alai ball has been levered at about 188 mph.
These speeds are taken over a very short distance from the throwing
arm on Earth, so would be nearly the same in space.
BTW, if an astronaut on the Moon wanted to "throw" something out of
Lunar orbit, he would need to throw at 5,315 mph (8,554 Km/h) which
would leave it barely moseying away from a Lunar orbit, but he would
need it to end up at a minumum of over 3,220 mph (5,188 Km/h) more to
then escape Earth.
Throwing things at these speeds is of course hypothetical given the
capabilities.
Back to the original question Earth meteorite possible? to comment:
These same capabilities need to be taken into consideration with
regards to the mass integrity of any Earth ejecta. Assuming an object
can hit Earth fast enough to impart sufficient velocity at cratering
which will survive the trip back up and more importantly an order of
magnitude more to rip it from Earth's gravitational grasp, is like
assuming you can find a Nolan Ryan to pitch a ball at about 12,000
mph. It is also a possibility that no physical Nolan Ryan exists.
Earth meteorites don't have a chance due to this reason, unless you
make one modifying assumption: That the original impactor causing them
creates a transient vacuum behind it long and straight enough for
backspauled material to find its way out. THAT is an extraordinary
claim unless we are talking major planet smasher and vapor
condensation in space just to make sure the ejecta aren't too small or
just plasma or molecules! Ojo, this means the cloud MUST condense in
outer space while it is moving away at these speeds. That just adds
another degree of complexity. Not impossible, of course. The jury is
still out. I'd repost a recent answer about 6 months ago I made
talking about the atmospheric dynamics required for Earth meteorites
to happen but I'm not good at maintaning these old met-list links as
some others :(
Best wishes,
Doug
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