Pluto Flyby

Pluto Flyby

Is the 2006 Pluto mission dead?

Or is a scaled down version still possible for that launch
window?

Does anyone have any good links or references on more
recent developments?

Remus wrote:

Pluto Flyby

Is the 2006 Pluto mission dead?

Or is a scaled down version still possible for that launch
window?

Does anyone have any good links or references on more
recent developments?

Try: http://www.jpl.nasa.gov/missions/future_missions.cfm
http://www.jpl.nasa.gov/missions/proposed_missions.cfm
http://www.jpl.nasa.gov/missions/index.cfm

Sam Wormley wrote:

Remus wrote:

Pluto Flyby

Is the 2006 Pluto mission dead?

Or is a scaled down version still possible for that launch
window?

Does anyone have any good links or references on more
recent developments?


Try: http://www.jpl.nasa.gov/missions/future_missions.cfm
http://www.jpl.nasa.gov/missions/proposed_missions.cfm
http://www.jpl.nasa.gov/missions/index.cfm

Also try http://www.boulder.swri.edu/pkb/ and http://pluto.jhuapl.edu/

--


Alex R. Blackwell
University of Hawaii

"Remus" wrote in message
om...
Pluto Flyby

Is the 2006 Pluto mission dead?

No, although it may slip to 2007 because of delays in assembly of the RTG
for the mission.

Or is a scaled down version still possible for that launch
window?

Yes, if the Los Alamos folks can deliver enough plutonium for the RTG. I
think I read that a reduced mission would need 170 watts, versus 220 watts
for the full mission. The team is also looking at methods of conserving
power during the outbound leg.

-Kim-

(Remus) wrote in message . com...
Pluto Flyby

Is the 2006 Pluto mission dead?

Or is a scaled down version still possible for that launch
window?

Does anyone have any good links or references on more
recent developments?

I presume the relevent (easiest) Pluto launch window comes around
every 12 years or so, with Jupiter?

Here's my own related question: why the devil didn't we take advantage
of economies of multiple production, to make more than one
Cassini-style probe when we're doing the first one? We need the same
dang thing for Uranus and Neptune. You know they have to gear up to
make at least 2 (the one to launch, plus a backup for Earth
simulation). So what's the bill to simply make a couple more? I mean,
how much different from each other need these outer gas giant orbiter
thingies be? You could replace the Titan-entry probe with a Gallileo
Jupiter-style entry probe for the primaries. Or even more simply, to
save on mass and flight time (and maybe give place for another power
module), you could leave off the entry probe completely, and still
have an orbiter capable of a lot of good science. And the big
differences in arrival time would let the data teams still do both
planets in sequence, with plenty of time between.

I have the feeling that exploring Uranus and Neptune one at a time is
going to cost 10 times what it would have, had we spent just a few
more bucks up front.

Steve Harris

"Steve Harris " wrote in
message m...
(Remus) wrote in message
. com...
Pluto Flyby

Is the 2006 Pluto mission dead?

Or is a scaled down version still possible for that launch
window?

Does anyone have any good links or references on more
recent developments?

I presume the relevent (easiest) Pluto launch window comes around
every 12 years or so, with Jupiter?

Here's my own related question: why the devil didn't we take advantage
of economies of multiple production, to make more than one
Cassini-style probe when we're doing the first one? We need the same
dang thing for Uranus and Neptune. You know they have to gear up to
make at least 2 (the one to launch, plus a backup for Earth
simulation). So what's the bill to simply make a couple more? I mean,
how much different from each other need these outer gas giant orbiter
thingies be? You could replace the Titan-entry probe with a Gallileo
Jupiter-style entry probe for the primaries. Or even more simply, to
save on mass and flight time (and maybe give place for another power
module), you could leave off the entry probe completely, and still
have an orbiter capable of a lot of good science. And the big
differences in arrival time would let the data teams still do both
planets in sequence, with plenty of time between.

I have the feeling that exploring Uranus and Neptune one at a time is
going to cost 10 times what it would have, had we spent just a few
more bucks up front.


....and one day, one of these one-chance-only going-a-long-way-all-alone 10
year missions is going to fly into a big rock just before it gets there. We
really should never be sending less than two of anything. Preferably built
to identical designs, but by different teams sourcing different components
where possible.

I really don't know how the Cassini team can sleep nights knowing that their
probe is all alone out there...

Just MHO of course

Ian

Kim Keller wrote:

Yes, if the Los Alamos folks can deliver enough plutonium for the RTG. I
think I read that a reduced mission would need 170 watts, versus 220 watts
for the full mission. The team is also looking at methods of conserving
power during the outbound leg.

True. And contrary to the recent Space.com story, which New Horizons
team members told me contains several factual errors, the NH team is
*not* considering any cutback in spacecraft capabilities or data
storage. They are considering a faster trajectory, which the NH team
believes could save at least 1 year on travel time. Specifically, this
option entails a relaxation in the July arrival constraint to an "any
month" constraint. The July arrival constraint was driven by a fairly
arcane secondary science calibration objective (i.e., measuring solar
wind scintillation along the Earth-Pluto line with the Radio Science
Experiment [REX]). If that constraint is relaxed, then arrival at
Pluto/Charon will occur, in the worst case, during October 2014. The NH
team also feels they can telescope the primary data transmission from 5
months down to 46 days by utilizing the maximum data transmission rate
available at Pluto. All of these options could result in 1 year
savings in travel time, which translates into ~5 W increase in power for
every year saved in transit.

The NH team is also considering options for more efficient operational
procedures to reduce power demand (e.g., disabling *excess* memory
storage not needed for science data. This is possible since the memory
allocation for the critical encounter sequence is many times the minimal
requirement).

--


Alex R. Blackwell
University of Hawaii

Steve Harris wrote:

Here's my own related question: why the devil didn't we take advantage
of economies of multiple production, to make more than one
Cassini-style probe when we're doing the first one?

See http://en.wikipedia.org/wiki/Mariner_Mark_II

--


Alex R. Blackwell
University of Hawaii

In article ,
Steve Harris wrote:
Here's my own related question: why the devil didn't we take advantage
of economies of multiple production, to make more than one
Cassini-style probe when we're doing the first one?

Mostly because it was already too expensive the first time. There *was*
going to be a similar (not identical, but similar) spacecraft built for
the CRAF comet-rendezvous mission. But CRAF was canceled to save money,
and Cassini itself was cut back in certain areas. Cassini owes its
survival to Huygens, pure and simple -- Cassini too would probably have
died, had there not been a major international commitment involved.

(And alas, Huygens is really quite specialized to Titan. There's no
comparable target at any of the other outer planets.)

...You know they have to gear up to
make at least 2 (the one to launch, plus a backup for Earth simulation).

Actually, no, it has been decades since such major missions built a
complete backup spacecraft. Subassemblies, yes, but not a complete spare.
There was no Galileo or Mars Observer backup, never mind a Cassini backup.

A lot of people thought there should have been a Galileo-Saturn mission;
there were minor provisions made for it in some of the development work.
Didn't get funded.

So what's the bill to simply make a couple more?

Making them wouldn't be that expensive, with the exception of the RTGs.
Launching them (on Titan IV) costs maybe three hundred million each.
Between spacecraft, RTGs, launch, and a decade or two of operations, it's
still probably the better part of a billion each. Not as expensive as
another start from scratch... but there isn't going to *be* another start
from scratch on that scale. In some ways, Cassini was the last gasp of
the Cold War.

...And the big
differences in arrival time would let the data teams still do both
planets in sequence, with plenty of time between.

Kind of, maybe. Note that the travel time isn't wasted -- much of the
detailed post-arrival planning for such missions is routinely left until
after launch, to help smooth out the operations load.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

Henry Spencer wrote:
Mostly because it was already too expensive the first time. There *was*
going to be a similar (not identical, but similar) spacecraft built for
the CRAF comet-rendezvous mission. But CRAF was canceled to save money,
and Cassini itself was cut back in certain areas. Cassini owes its
survival to Huygens, pure and simple -- Cassini too would probably have
died, had there not been a major international commitment involved.

(And alas, Huygens is really quite specialized to Titan. There's no
comparable target at any of the other outer planets.)

Or any planet really. There are only 4 rocky planetary
bodies with atmospheres in the Solar System (Venus,
Earth, Mars, Titan). Huygens might do well as an Earth
lander, or a Mars lander, but in either case it wouldn't
provide much new data. It probably wouldn't survive
long on Venus, so it would be a short-lived atmospheric
probe. Which is what it would be if used on any of the
gas giants. It's a shame really that Cassini didn't
have a Saturn in-situ probe. It could have been very
much more sophisticated than Galileo's, it could even
have provided imagery, most likely. Plus, it would be
very useful to have everything on the table to hit
the other gas giants with. Or, for that matter, to hit
the Jupiter and Saturn multiple times with. The
atmospheres of the Jovian planets are really very much
more dynamic than anything else in the Solar System, a
single probe really tells us very little.

Maybe somebody will design a low-mass balloon borne
jovian atmospheric explorer craft that can hitch a ride
on JIMO or somesuch. Would be nice...