Where is New Horizons now Options

[Planet X]

UPDATE! On 06/04/2008, at 18:05:25 UTC, the NH spacecraft reached 1.5 billion km from the sun. The spacecraft's distance from Earth, by comparison, is 1.352 billion km. NH is now only 3.219 billion km from Pluto and traveling at a rate of 16.921 km/s. Saturn orbit crossing is now just 4 days away. Later!

J P

[dmuller]

I have rushed a beta-release of the New Horizons real-time simulation at http://www.dmuller.net/newhorizons/ Not all data is in yet, but the important events such as crossing the Saturn orbit and distance from Sun (250,000 km to go to the 1.5 bn distance from the Sun ... the solar system simulator rounds to full million kms) are in.

[MizarKey]

I really like your countdown timers, very nice work. Perhaps you could develope something smaller to be used as a google gadget?

[dmuller]

Saturn Orbit Crossing: I have analyzed the JPL's Horizons system data and I now estimate that New Horizons will cross the Saturn orbit on 08 June 2008 at 08:16am SCET UTC. Saturn will reach the same point (in the xy plane) on 02 Sep 2017 15:49 Saturn time. The xy-plane error of this analysis is around 380 km.

MizarKey: Good idea ... I can look into that down the road. First I want to populate the scripts with data.

[dmuller]

I have received a question about the definition of the Saturn orbit crossing:

(edited for formatting) Concerning the upcoming Saturn orbit crossing, how exactly are you defining this?
According to the thread on UMSF, Alan Stern says this is when the heliocentric distance of NH first exceeds that of Saturn and will occur on 2008 June 08, as your simulator also indicates.
However, according to my own calculation this has already occured, on 2008 March 21 (to be precise at 10:55:52 UTC/SCET). At this time the distance of both objects is 9.287447 AU.
On June 08 NH's distance already exceeds Saturn's by about 0.75 AU, but this is still within the distance variation of Saturn's orbit, so you may be using a different criterion for determining when NH crosses it.

The " thread on UMSF, Alan Stern" refers to this:

These planet orbit crossings are based on whatever day we pass the distance of the planet, so although we are currently beyond Saturn's semi-major axis, Saturn is near its aphelion and we don't count the orbit crossing until we are further out than Saturn itself is.

I used the following:

The Saturn orbit crossing is the point in space where the trajectory line of New Horizons intersects with the orbit line of Saturn as seen from above. So the intersection is in the xy plane. Of course, this works only in 2 dimensions as NH and Saturn have different elevations above the ecliptic at that point. On 08 June 2008 at 08:16am SCET UTC, New Horizons will be at the same x,y coordinates as Saturn will be on 02 September 2017 15:49 Saturn UTC (well ... within a 2 dimensional error distance of 378km since the analysis was done in minute intervals and not seconds)

This is also what is shown on the New Horizons website as it shows "crossing the line" rather than being as far from the Sun as Saturn. Whilst this does not tally with the definition Alan Stern gave, his definition is possibly more meaningful, since by being further away from the Sun than Saturn (i.e. Cassini) now makes New Horizons the 5th farthest man-made object from the Sun (not counting rocket stages etc)

EDIT: corrected mission name ... thanks mps

[mps]

The Saturn orbit crossing is the point in space where the trajectory line of New Messenger intersects with the orbit line of Saturn as seen from above.

"New Messenger"? Also a cool name, though

[dmuller]

"New Messenger"? Also a cool name, though

Aaarrrggghh it just had to happen sometime. I dont know why I keep mixing up NH and Messenger ... especially since NH - the one to Pluto - is my favorite current mission. Lack of holidays? Old age? Geez I hope I make it to 2015 ...

[Alan Stern]

UMSFers-- As of last week, New Horizons is Twittering: NewHorizons2015 is the Twitter username for those interested.

-Alan

[jamescanvin]

Thanks Alan, I'm following.

Here's a direct link for lazy people.

http://twitter.com/NewHorizons2015

[Alan Stern]

Thanks Alan, I'm following.

Here's a direct link for lazy people.

http://twitter.com/NewHorizons2015

James-- Excellent!

Alan

[ElkGroveDan]

I'm in now too!

[ugordan]

In, too! Can't help but wonder though - what will become of Twitter 7 years from now seeing how fast "it" things change on the net...

[climber]

Argh! I was able to sign for Phoenix & LRO and can't get in here. Can remember what to do to sign in. Some help needed please

[nprev]

Caveman question, here...what the hell does Twitter do? I don't subscribe to jack on my cel, only hit the Net from PCs (at work it's quite limited).

Please, somebody, tell me what the flint & bearskins are good for here!

[Del Palmer]

Nick, I have the same question. At first I thought it was a broadcast model where one user updates many others. But reading a recent Cassini report suggested it was more like an instant-messaging service ("For Cassini, the user submits a question or message and members of the flight team respond from the perspective of the spacecraft.") Even more confused now...