[meteorite-list] Just Another Question

From: AL Mitterling <almitt_at_meteoritecentral.com>
Date: Sat, 31 May 2008 13:30:46 -0400
Message-ID: <48418B46.3080806_at_kconline.com>

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

mexicodoug at aim.com 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
Received on Sat 31 May 2008 01:30:46 PM PDT