So Phoenix wont qualify, again :-(

2 1/2 days until Dawn enters the Martian Hillsphere ... and a minor trajectory update in the kernels: closest approach on 18 Feb 00:29:06 UTC at an altitude of 549 km.

I have now implemented the notional DSN tracking for Dawn (or to be more precise: for Mars) for the next 16 days at http://www.dmuller.net/dawn

It has indeed turned into the worst natural disaster in Australia, and sickest of it all is that some fires were deliberately lit. 108 have perished (there are fears that this number could go to 170) and some towns are still threatened by fires. It's a real tragedy.

Though I am not directly affected, we have major bush fires in SE Australia. News just out (http://www.abc.net.au/news/) report that 14 people perished (maybe up to 40) in bush fires near Melbourne, Victoria. It's a beautiful country side were it happened, been there a couple of times. Scorching heat (Melbourne 47, Western Sydney 42, my place 40) and strong winds didnt help the situation. Lets hope it doesnt get any worse, NSW's having a hottie tomorrow.

Edit: not to forget, two states up in Northern Queensland they have a massive flooding event there

Ah never too old to learn something new I should be able to vary the length of the seasons to match Emily's website ... in due course ...

I tried to include some information on the current season of Mars into my realtime simulations (Mars clocks). Now one way of doing so that I can think of (but haven't really seen it around) is to calculate Earth equivalent dates for Mars, such that summer solstices are always on the "21-Jun" etc. Naturally these "days" (based on orbit around Sun rather than rotation of Mars) last about twice as long as on Earth (more precisely: 686.9 / 365.25 times as long). Using the only solstice I know (summer solstice 25 Jun 2008 ... Phoenix was there), this approach says that it would be 23 October on Mars now. Does that make sense? Is that useful?

The SPICE kernels seem to indicate a flyby altitude of 568km

Thanks to a very kind soul who provided a very easy solution (easy = I can handle it!) I can now load SPICE kernels into the realtime simulations, greatly enhancing the accuracy of the trajectory of some missions. First update applied to Dawn. Go Celestia!


You're welcome! Glad that it is of use.

Mmmm thanks but no thanks. I rather sweat it out I think.

Well Happy Birthday Stu!

Celebrate and then have a good rest, after all, you've traveled more than 41 billion km (275 AU) around the Sun so far! I could barely resist writing a realtime simulation of your life for this occasion, but I guess you're lucky, it's just way too hot now (we had 41.8 C yesterday) and I'm too busy

Just to let you know the Cassini realtime simulation at http://www.dmuller.net/cassini finally includes trajectory data and some fixes to make it load faster.

On that note, if anybody has a standard solution (like an exe file) of converting NAIF SPICE kernel files into (x,y,z,t) coordinates, pleeeease let me know :-)

Thanks for your reply! I have the toolkit ... ... which is the problem. I wasnt actually looking at it for Juno, but for some other missions and events (especially C/A) where Horizons is not up-to-date or as accurate as I'd like it to be. So if anybody has some ready-made SPK to (x,y,z,t) converter (the kind of one-click-and-it's-done) then I'd love a copy of it :-)

EDIT 26-Jan Thanks to a very kind soul who provided a very easy solution (easy = I can handle it!) I can now load SPICE kernels into the realtime simulations, greatly enhancing the accuracy of the trajectory of some missions. First update applied to Dawn. Go Celestia!

A generic question about trajectories: does anybody in here know how to work the NAIF Spice Kernel tools/files (or whatever it's called ...) I think they would provide more accurate information for my realtime simulations than Horizons, but I just cant understand on how to work them. All I'd need is something to convert the SPK files into the good old 4 dimensions (x,z,y [wrt to solar system barycenter] and time). Feel free to send me a private message as well.

Thanks for your help in advance!

Well the Horizons webpage states the following, so get your resuts emailed to you for close approaches:

According to the Dawn ops team, the best estimate of the closest approach to Mars is February 17 at 16:28:55 PST +/- 35 seconds (Spacecraft Event Time). They will continue to refine the time over the coming weeks, with the principal uncertainty being the effect of RCS activity to desaturate reaction wheels. Also there will be no high resolution images of Mars during closest approach, and no observations of Mars are possible whilst Dawn approaches Mars because the Sun is at too close an angle to Mars. After all, the Mars flyby is just a means to reach Vesta, and would not have been in the flight plan had the mission launched earlier.

EDIT: The source of the above information was provided by Marc Rayman, Chief Engineer of the Dawn mission.

I somehow seem to have missed these two mission extensions completely. My apologies. Very preliminary Stardust realtime simulation page now at http://www.dmuller.net/stardust - I hope I have trajectory data in there within 48 hours.

At last I have put a preliminary version of the EPOXI realtime simulation online: http://www.dmuller.net/epoxi

As usual, please report any bugs and further mission information you may have :-)

Incidentally I noticed a "close-ish" Earth flyby on 29 Jun 2009 around 8am UTC, distance 1.3 million km

please dont ban this post:

Plutophobia: the fear of being demoted

PDA - Peanut Deficiency Anaphylaxis: a serious and fatal condition suffered by early space probes. Occurrence can be reduced by peanut intake at mission control prior to critical event. Not to be confused with
PAD - Peanut Allergy induced Depression which must be felt by all UMSFer who are allergic to peanuts.

Also I had visitors to my website report acute stare-at-numbers-hypnosia ... people just staring at my realtime simulations and watching the numbers tick by for an extended period of time!

It has been a rather short but intense mission indeed. Feels like we've heard "Phoenix ... Phoenix has landed. Welcome to the Northern plains of Mars". Made a lot of friends thanks to Phoenix!

I've yet to calculate the exact hour and minute, but this info is to within one day exact (and in your local timezone):
http://www.dmuller.net/newhorizons
Source for that information is New Horizon's website in the first place :-)


that is the current distance between New Horizons and Pluto. It's a tad bit further to fly to the point of closest approach, which is still 3.2 billion km away

BTW I read that there's gonna be a small TCM in 2009

I was wondering about the capture itself. Would a delta-v of 150m/s be enough to recapture ICE into Earth orbit (possibly with a Galileo-style Moon flyby)? I dont think the craft was designed for aerocapture, and aerobraking it from a highly elliptical orbit into a more normal orbit may get rid of any cometary evidence on the craft. And then the bigger question: what is going to actually capture the craft? The Shuttles supposedly stop flying 4 years before ICE returns to Earth.

Note to self: keep 2014/2015/2016 free of appointments. Will be a busy time: Dawn, Rosetta, New Horizons, possibly MSL, ExoMars, Juno ... EDIT and of course: ICE!

Indeed: http://www.heavens-above.com/solar-escape.asp

I think I saw that Cassini shot an image of Alpha Centauri rising over the rings (if memory serves me right). I dont recall anything on Uranus or Neptune

Had the launch been delayed by a year, or that IAU Pluto vote been held earlier, I guess the 10th item would have been one (or more) IAU membership cards