[FPSPACE] China's space probe hits moon

[Geert Sassen]

According Chinese media one of the reasons for this controlled crash was
tracking a descent trajectory in view of a follow up lander. Maybe I am
reading too much in this statement, but given the fact that mascons etc are
very local phenomena, tracking a descent trajectory only makes sense if you
follow more or less the same trajectory as the lander is supposed to do
(same Apollo 10 prior Apollo 11), otherwise this data will not make much
sense. Same for making high res images from low altitude prior to the crash,
which they supposedly did.

So, IF this is correct, it might be that the planned landing site for the
(first?) Chinese moonlander will be close to the crash site of this probe.
Otherwise crashing the probe in this position (on reasonable flat Maria
ground) does not make much sense.

Speculating still further there is one more interesting item: this crash
site (and intended landing site?) is not far from the Soviet Luna 16 landing
site and the meridian of 60 deg. east. All the Soviet sample return missions
landed close to this longitude, simply be course this is the only place on
the moon which allows a direct-ascent trajectory back to earth without
midcourse corrections. Now this is highly speculative, but why (with the
whole moon the chose from) would they be planning a landing especially in
this area? Given that Shenshou is derived from Soyuz, might it be that their
moonlander will be derived from the Luna Y8E/Y8M probes (which were
restricted to landing in this area as otherwise they couldn't return to
earth)... If you were planning to fly a Y8E derived sample return mission,
then this is indeed one of the best places to land it. If you are planning
'just' a normal lander, lots of other places are probably far more
interresting and this landing site doesn't make much sense..

Once again, I'm probably reading too much in the whole statement, but it's
just weird..

Regards,

Geert.


On Sun, Mar 1, 2009 at 7:06 PM, Sven Grahn <svengrahn at telia.com> wrote:

>  http://www.chinadaily.com.cn/china/2009-03/01/content_7523687.htm
>
> Sven Grahn
>
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-- 
Geert Sassen
weblog: http://geertsassen.web-log.nl
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