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Lord Jubjub
2006-Jan-18, 02:24 AM
It launched at 1400 EST on the 18th of January (after a delay of 48 hours), this is a rough calculation when it will cross the planetary orbits. The pre-Jupiter dates assume 57600 km/hour. The post Jupiter dates assume 72000 km/hour (NH media guide). The Mars date was from a NASA comment during launch. The Ceres date is porportional to that.

Moon orbit: 19 Jan 2006 at 2300 EST
Mars orbit: 16 April 2006
Ceres orbit: 30 Oct 2006
Jupiter orbit: 27 February 2007
Saturn orbit: 30 January 2008
Uranus orbit: 12 May 2010
Neptune orbit: 12 Dec 2012
Pluto orbit: 14 July 2015

Is there a fairly simple derivation to obtain the decelleration due to the Sun's pull? I passed college calculus with flying colors.

cyswxman
2006-Jan-18, 05:11 PM
Do we just add a day to each of the above dates, for each day the launch is delayed? (Something tells me it's not quite that simple)

pumpkinpie
2006-Jan-18, 05:27 PM
Do we just add a day to each of the above dates, for each day the launch is delayed? (Something tells me it's not quite that simple)
I'm sure it's not that linear. According to this launch window (http://spaceflightnow.com/atlas/av010/051129windows.html) summary, a delay in launch 3 days--Jan 31 to Feb 3--delays the arrival at Pluto from 2016 to 2018!

ToSeek
2006-Jan-18, 06:27 PM
Do we just add a day to each of the above dates, for each day the launch is delayed? (Something tells me it's not quite that simple)

According to Wikipedia (http://en.wikipedia.org/wiki/New_Horizons), any launch before the 28th means an arrival on July 14, 2015. The 28th goes to August, the 29th-31st to 2016, Feb 1-2 to 2017, Feb 3-8 to 2018, and so on.

cyswxman
2006-Jan-18, 06:52 PM
Hmm, so a launch anytime before the 28th will not affect the arrival date? Then again, what's a few days after 9 years?

ToSeek
2006-Jan-18, 09:07 PM
Hmm, so a launch anytime before the 28th will not affect the arrival date?

That's what it says, but don't ask me to explain why.

formulaterp
2006-Jan-18, 09:59 PM
I think there are 2 factors to consider:

1) The first deadline (I believe Feb. 2) is needed to use Jupiter for a gravity assist. Without it you pass up a substantial boost in delta-v, necessitating a longer flight.

2) Pluto, Charon, the Earth, Sun and New Horizons all have to be in juuuusst the right positions relative to each other in order to perform the occultation experiments. The biggest variable is the Earth. If you miss a specific launch deadline you need to wait until the Earth swings back around again, and you need the spacecraft to fly a different flightpath so that it arrives at the right time. Thus you have the staggered arrival dates.

harlequin
2006-Jan-20, 12:51 AM
Will there any observations made specifically for the patch of sky that New Horizons could go to in order to find the best candidate for a post-Pluto flyby of a KBO?

I am right in assuming that the KBO, that NH visits after Pluto might not yet be discovered?

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NASA's timeline (http://pluto.jhuapl.edu/mission/mission_timeline.html) says that New Horizons will go 3 to 4 times closer to Jupiter than Cassini did. Given that Cassini was able to do some really nice photography during its Jupiter flyby and that NH has some really good cameras, will NH be able to photograph anything in the Jovian System better than previous spacecraft?

Lord Jubjub
2006-Jan-20, 02:01 AM
I think Galileo probably took better pictures than NH could ever take.

Lord Jubjub
2006-Jan-20, 04:27 AM
OK, this is maybe somewhat pointless, but I found more accurate speed numbers and updated my initial post with those number. If this post somehow manages to stay going over the next 10 years. . .

The media guide definitely states that the NH team is expecting to get some nice shots of Jupiter and that they'll be better than what Cassini took.