New Horizons: Pre-launch, launch and main cruise, Pluto and the Kuiper belt Options

[cIclops]

Yes it's happening after all these years, the mission to the last planet!

And maybe to celebrate the confirmation of budget, NASA approval preparations and the fueling of the RTG (radioisotope thermoelectric generator), there is an updated web site at http://pluto.jhuapl.edu/

Launch will be January 2006 with arrival at the Pluto Charon system July 2015 (mark your calender!) and then on through the Kuiper belt during 2016-2020 and beyond.

20.8-centimeter telescope for 100m resolution at closest approach
IR/UV spectrometers
2 x 8GB data recorders
data rate: 768 bps (sic) to 70m DSN
465kg including fuel
$650m

336 days to launch

[RNeuhaus]

Good explanations. I was able to grasp them.

I tought the spin had the purpose to distribute uniformly the heat, cool and solar radiation and cosmic as I have learned it from others spacescrafts which orbit around the Earth and also to Moon and Mars.

As the spacecraft is going farther from the sun, the spin for this space might be less importance every time it is moving further away. Now I realice that the spin helps the spacecraft to avoid any wobbing during its trajectory and also to helps to manage better the thrusters after knowing the mass' properties of NH.

Well, as I see it, NH will be spinning on all way toward the Pluto. It would become an even more complicated to control the pointing of any navigation instrument to stars, to photograph any images on planets when the spacecraft is spinning.

Then maybe, before to take any picture, or any measurement, one of three (x-y-z?) reaction wheels will be activated to stop before conducting any science activities when it is flying-by to any celestial bodies (Jupiter, Galliean Moons, Saturn?, Uranus, Neptune and Pluto and its three moons).

Here, I have an inquietant question. It is related to reaction wheels as it is one of the most delicate since it has short Meant Time Between Failures. Will the NH have enough redundancies to cover all NH's lifetime trip to Pluto. I am thinking that the spinning factor will help to NH to avoid the use as less as possible the wheel reactions or not?

Rodolfo

[john_s]

Then maybe, before to take any picture, or any measurement, one of three (x-y-z?) reaction wheels will be activated to stop before conducting any science activities when it is flying-by to any celestial bodies (Jupiter, Galliean Moons, Saturn?, Uranus, Neptune and Pluto and its three moons).

Here, I have an inquietant question. It is related to reaction wheels as it is one of the most delicate since it has short Meant Time Between Failures. Will the NH have enough redundancies to cover all NH's lifetime trip to Pluto. I am thinking that the spinning factor will help to NH to avoid the use as less as possible the wheel reactions or not?

Rodolfo

That's correct, we stop the spin when we want to make observations. However we do not carry reaction wheels- instead we use thrusters for controlling the spacecraft orientation and spin. This saves us mass compared to using reaction wheels, and eliminates a moving part that might fail, as you say. However it means that we have to be conservative in our maneuvering, because we have only a limited fuel supply. So spin mode helps us save fuel.

[BPCooper]

Spin test Monday:

http://www-pao.ksc.nasa.gov/kscpao/images/.../05pd2498-m.jpg

[Alan Stern]

New Horizons highlights for the week ending 11/18/05 include:

* Conducted Autonomy Review on 11/15
* Conducted Pre-Fueling Review on 11/16
* On basis of the above, decided to delay hydrazine fueling by six days to allow
for additional autonomy testing on the spacecraft and NHOPS.
* Observatory hydrazine fueling now scheduled for Sunday, 12/4. No change
to beginning of launch window; holding firm at 1/11/06.
* Completed dry spin balance on 11/17. No surprises.
* MSIM 4 Part 3 repeat for pactice began 11/17 and is scheduled to complete 11/19.