Nh - The Launch Thread, Godspeed little one |
Nh - The Launch Thread, Godspeed little one |
Jan 16 2006, 03:08 PM
Post
#1
|
|
Founder Group: Chairman Posts: 14448 Joined: 8-February 04 Member No.: 1 |
I thought it was time, with the Atlas V about to roll out - for a new thread for NH for the launch etc.
Someone asked over at the HZ just how NH can go so fast, this was my reply.... QUOTE How do you get a spacecraft to Jupiter in under a year? Easy. Make it very very light, and put it on a very very big rocket. The config of Atlas V rocket being used to launch NH (551 - 5m fairing, 5 solids, and one engine on the Centaur stage ) would typically put 8,670kg into GTO or 20,520 into LEO. New Horizons is 478kg, and it's Star 48B 3rd stage is 2,137kg - so instead of hauling 20 tons, this vehicle is hauling about 2.5 tons thus you get a HUGE velocity out of it. AND, once it's done that, you have the final kick of the 48B, 591 thousand kgs-s (thus accelerating is all a further 3.5 - 4km/s ball park speed, if my maths is right) At launch - the vehicle is 573,160kg. NH is 0.083% of it. Imagine the Apollo entry capsule on top of a Saturn V...tiny tiny tiny... that was 5,800 kg on a 3,038,500kg rocket - 0.191% - more than double that percentage of NH. The cutaway's are almost comical, with this tiny gold-clad box on an enormous vehicle. Basically - it's a LOT of rocket, and not a lot of payload. For comparison, look how much fuss was made of Stardust that entered so quickly. It took >16 hrs to get from the distance of the moon to Utah. NH makes that journey in 9 hours One thing the NH mission is not short of, is superlatives. I'm not one for good luck charms (although I'll eat peanuts during a Martian EDL with the best of them), but this mission has been so long in coming, that it deserves every ounce of luck it can have - the best, most accurate launch possible, the cleanest checkout, and incident free cruise to Jupiter. Goodluck and Godspeed little one, we're with you every step of the way. Doug PS - Alan, you're a credit to your field, spending so much time answering questions and writing the PI Perspectives, it's been a hell of a journey! |
|
|
Jan 16 2006, 06:47 PM
Post
#2
|
|
Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
I'm checking out the really wonderful Expendable Launch Vehicle Countdown Portal at KSC's website, and there's a lot of info there, but I'm finding it confusing. Can someone help straighten me out?
- First of all, the clock showing GMT and EST time shows 18:00 GMT when my own clock shows 10:41 (PST). So it appears that on my machine at least the applet appears to be running behind by 41 minutes. Does anybody else see a similar delay, or is the clock on the display synchronized to yours? - Second, the "Window opening time" is listed as 016:17:25:00, which I think is a ddd:hh:mm:ss display. But if that's the case, that refers to a time that passed about an hour ago, and I don't think NH has launched yet Am I reading this wrong or is the applet messed up and does anybody else see the same thing? --Emily -------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
|
|
|
Lo-Fi Version | Time is now: 31st October 2024 - 11:10 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |