Date: Mon, 06 Dec 1999 00:34:28 +0100
From: John Walker
Let me contest this. One may argue against Dan Goldin's
"Faster, Cheaper, Better" approach (for example, the quip
"choose two of the above"), but the reality is that *no*
missions were landed on Mars between 1976 and the 1997 landing
of Pathfinder. In my opinion it's a lot better to launch
a couple of US$100-US$200 million missions every 26 months
and have some work and some fail that blow it all on a
US$1000 million mission every 10-20 years (such as Mars
Explorer, lost in 1993) which destroys the professional careers
of the investigators depending on its results if it's lost.
With a regular schedule of lightweight missions, you can
shrug your shoulders and say, OK--better luck in a couple of
years.
Jack wrote:
Jack wrote:
I hope communications are established with MPL in the
near future but, if not, I'd say "Stay the course".
These lightweight probes not only multiply our opportunities
to visit other worlds, they drive miniturisation, the
significance of which should be evident to any reader of
this list.
[Jack]
Agreed, we need to stay the course. Ad Astra!
This is like what happened with Challenger. Fortunately, this time, no one
was killed. I hope NASA proves me wrong on this one.
Me too. But unless the mission is indeed judged a failure and a
board of inquiry assigns blame to management, it may simply
be one of those things that happens when one deploys cutting
edge technology (for example, the pulsed descent thrusters
on the lander) for the first time. Or, the lander may have
simply hit a big rock and toppled over. The Viking 2 lander
would have suffered this fate if it came down a couple of
metres from its fortuitous landing site.Correction: We are not getting what we are paying for!
You may. If one spent US$1000 million on each of these
lightweight missions, one might be able to afford orbital
relays which would diagnose the causes of mission failure.
As an engineer, I don't think that's cost-effective--you can
do a lot more missions by not providing for the worst case,
and you can probably return a lot more science over a decade
by accepting a failure rate of 25% for missions which cost on
the order of 15% of a battlestar.