1991 VG

>
> I was surprised by the quick travel times, but this was the
> remark that
> really took me by surprise. And to think there are space
> advocates who
> consider "the next logical step" after the moon to be a trip
> to a planet so
> distant that the Earth would appear as a tiny blue-white
> star. Any who
> consider Mars the obvious next stop are simply suffering from
> a bad case of
> planetary chauvinism.

I can't read the original message; so I have no idea whether the original
study here has been linked to. If not, the url is
http://www.aas.org/~dps/decadal/whitepapers/jones_120701.doc ; if so, please
accept my apologies for an unnecessary duplication.

The problem here is that there are no current trajectories for these short
duration missions - the two trajectories referred to here are historical.

On the other hand, we are steadily adding objects to our data base which
might allow these missions - 2002 AA29 looks particularly invitingly; with
its six-monthly close flybys & ridiculously low relative velocity - & making
the flight plans more realistic (total mission durations up to 12 months;
which the MIR experience shows is very doable with current technologies),
opens the potential for Lunar/Earth gravity assists which make the total
delta vs for the missions quite remarkably low.

The newness of these trajectories is the main reason why the debate is still
tied to the old Lunar/Martian dichotomy, of course - given the technology
you >don't< need to invent to fly these missions (any specialised lander
technology for eg) & the low delta v, the sheer simplicity of these flights
mean that they would be front runners for the next human exploration
initiative if the numbers were more widely known.

I have noted with some interest that the PRChinese - who have some serious
manned space exploration plans, mostly concentrated on the Moon - are doing
serious work on orbital manouevring around small bodies. Whether this means
they might attempt an envelope stretch to a asteroid between a manned Lunar
orbiter & an actual landing is difficult to tell; but given the way my
in-laws think, probably likely....

Live in peace
Robert.Clements@...
endeavour2 project http://www.geocities.com/robtclements/endeavour2.html>