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Yes please feel free to spread the word ... it's meant to be seen after all!
Daniel

Announcement for those following the Phoenix Real-Time Simulation at http://www.dmuller.net/phoenix
Just in case anything goes wrong with the server, there is a backup / mirror site of the script at http://www.dmuller.com/phoenix
Enjoy watching the landing! Daniel

With 4 days to landing, and after 3,700 website visits (a lot for a website of mine) I can announce that the final version of the real-time simulation is now online at http://www.dmuller.net/phoenix. I do not intend to make further changes unless the entry interface and/or nominal landing times change "significantly". Such changes can be made as late as just after TCM 6. Some important information:

Download Speed: I would expect the simulation to take longer to load on May 25. At the moment, all position data is correct on an hourly basis and interpolated in between, but soon this will change to a minute-by-minute basis and requires more data to be loaded into the simulation. Starting from about 30 minutes before landing, all the remaining trajectory information will be loaded into the script when it does its auto-reload, or is accessed for the first time. This may take a while longer than usual, but avoids having to reload the script during the crucial EDL phase. Be patient :-)

Mirror Site: In case anything goes pear-shaped, the simulation is also running at http://www.dmuller.com/phoenix. You can use this site if the main page goes down or becomes too slow. I will not be able to attend to the script or server issues in the last 24 hours before landing as I wont be home, and the server sits in the US where there is a long weekend. On that note: could anybody record the NASA TV feed for me (preferably the one without commentary) ... I'll paypal for postage etc?

Beyond Phoenix: given the interest in the script and feedback I have received, I will create similar scripts in due course. However, I do need to catch up on my "proper", space-unrelated :-( work a bit before continuing (as a freelancer it's easy to 'scale back' work for other more interesting activities, but unfortunately the bank account starts to hurt a month later ...). Top of the list will be New Horizons (because I like that mission) and Messenger (for the upcoming Mercury flyby 2). Updates will be posted to where the Phoenix script sits at the moment. I will also look into creating a spaceflight (& related) outreach online library, so if anybody has any suggestions, you know where to find me.

7.5 million km to go. Good luck Phoenix, we're all waiting to hear from you from the surface of Mars.

Go, Phoenix!

Daniel

The time between Entry Interface and Landing seems to have shrunk from 470 secs (graph) to 440 secs based on the entry interface and nominal landing time that I've been given. I have taken my events from that chart and adjusted for the 30 sec difference.

The time between "lander separation" and "throttle up" seems particularly scary. Phoenix will be in freefall, albeit for 3 secs only, but with only about 500m altitude (5 secs of flight) to spare.

Thanks spacenut for the welcome!

Some news to share: The Phoenix real-time simulation at http://www.dmuller.net/phoenix now has both Spacecraft Event Time and Earth Received Time. ERT hasnt been tested as much as the SCET version yet, so it may uncover some hiccups but I hope that wont be the case.

Also, for those planning to watch the landing live on the internet, I have received the following message from JPL:

cIclops:

now that makes sense!

I wouldnt have a clue. Havent found anything on the net that is as detailed as that.

Daniel

All times on the real-time simulation for now are spacecraft event time (SCET). Add 920 seconds to get Earth Received Time (ERT). An ERT version of the simulation should be up soon.

I've been told that Phoenix will send near real-time engineering data and first image due 2 hrs 40 minutes after landing. Likely all data through MEX / MRO / ODY since landing is just on the Earth terminator. With three monitoring crafts aloft there shouldnt be too many gaps in the coverage, I hope (dont they have orbital periods of 2 hours or so each?)

But yes plenty of opportunities to go blue. The first one at 6 hours to entry interface when my alarm clock rings at 4am local time to drive to the Canberra DSN station (4 hours drive) to join the folks there  :shock:

Daniel

Thanks cIclops for the link. Entry Interface and Landing times are as advised by one of the DSN stations who received that info straight from the Phoenix team about 1 month ago and after the 13km shift of the landing ellipse. Note that there is an uncertainty in the landing time of +/- 30 secs due to uncertain atmospheric conditions. The countdown script assumes a nominal landing, on the dot and on the spot.

Interestingly enough the Phoenix mission site and the NASA Phoenix page  countdown clocks differ by 2 minutes ... which got me to seek further details in the first place. (Sorry cant post the links here because this is my first post to the forum and postings of links seems not possible yet.)