New Horizons: Getting Closer - December 27, 2005

http://pluto.jhuapl.edu/overview/piP...e_current.html

The PI's Perspective
Alan Stern
Getting Closer
December 27, 2005

This past week was a busy one. Mission operations practices continued,
as did engineering paperwork closeouts. Other major activities
included:

o The final tasks associated with mating the spacecraft and third stage
to
our Atlas launch vehicle.
o A suite of integrated electrical testing of the spacecraft-third
stage-Atlas stack.
o A stress test of the New Horizons spacecraft Power Distribution Unit
(PDU) in response to an anomaly investigation surrounding a pair of
commands the PDU dropped before executing on Nov. 19-20.
o A dry run of radioisotope thermoelectric generator (RTG)-spacecraft
mating activities.
o Draining and preparations to begin drying our Atlas fuel tank in
preparation for boroscope inspections set for Jan. 3-4.
o The final NASA Headquarters prelaunch mission review.
o A mission press conference held at NASA Headquarters; this was
accompanied by the release of the mission press kit, which is
available
at http://pluto.jhuapl.edu.

In other news of the week, New Horizons science team collaborator Marc
Buie and four coworkers submitted a research paper to The Astronomical
Journal describing some new results about Pluto's just-discovered small
satellites, which have been temporarily dubbed "P1" and "P2." You can
find this paper posted on the Web at:
http://xxx.lanl.gov/abs/astro-ph/0512491.

In brief, Buie et al. faintly detected P1 and P2 in almost two dozen
Hubble Space Telescope images of Pluto made in 2002. They then used
that
data to refine the orbits of the new satellites. They also managed to
eke out colors for the two moons: P1 is neutrally colored, but P2 is
red. Why are they different? No one knows, but variety is the spice of
life, and these new results indicate New Horizons is going to see a lot
of that when it visits the Pluto system.

The holidays upon us now are providing a well-earned break for most of
the New Horizons team. With that break, also comes a time of
reflection.
We are very proud of the spacecraft and launcher we built and tested in
2005, and we are even prouder to think that we're so close to flying
the
capstone mission in the initial reconnaissance of the planets.

I'll post my next update right after the start of the new year. See you
then.