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Tom O'Reilly
Does anyone know where I can access a daily ephemeris for the Curiosity landing site? E.g. Sun rise/set, Earth rise/set, MRO/Odyssey/Mars Express transits, etc?

Thanks,
Tom

Adam Hurcewicz
QUOTE (Tom O'Reilly @ Aug 6 2012, 05:57 PM) *
Does anyone know where I can access a daily ephemeris for the Curiosity landing site? E.g. Sun rise/set, Earth rise/set, MRO/Odyssey/Mars Express transits, etc?

Thanks,
Tom


Hi, i use Guide software to calculate sunrise/sunset on Mars
Sunrise at 20:10 UTC - Transit (Alt 74°) at 02:15 UTC - Sunset at 08:20 CET

Earth rise at 17:45 UTC - Transit (Alt 62°) at 23:45 UTC - set at 05:45 CET

MRO/Odyssey/Mars Express I don't know, I don't have good orbital data of this.

Adam
jmknapp
QUOTE (Tom O'Reilly @ Aug 6 2012, 10:57 AM) *
Does anyone know where I can access a daily ephemeris for the Curiosity landing site? E.g. Sun rise/set, Earth rise/set, MRO/Odyssey/Mars Express transits, etc?


It can be calculated with the NAIF SPICE data. If such a facility is not already available maybe I'll set up a web page.
Tom O'Reilly
QUOTE (Adam Hurcewicz @ Aug 6 2012, 09:20 AM) *
i use Guide software to calculate sunrise/sunset on Mars
Sunrise at 20:10 UTC - Transit (Alt 74°) at 02:15 UTC - Sunset at 08:20 CET

Earth rise at 17:45 UTC - Transit (Alt 62°) at 23:45 UTC - set at 05:45 CET

MRO/Odyssey/Mars Express I don't know, I don't have good orbital data of this.


Very cool Adam - what is "Guide" software? (LOTS of google results searching for that!)

Does anyone know of a publicly-accessible MSL surface operations page or other resource that would include this information?

Thanks,
Tom
Adam Hurcewicz
QUOTE (Tom O'Reilly @ Aug 6 2012, 07:58 PM) *
Very cool Adam - what is "Guide" software? (LOTS of google results searching for that!)


It's here http://www.projectpluto.com
Very good soft.

Adam
jmknapp
I made an almanac up through Sept. 30 showing the MRO, ODY and MEX passes along with sun/earth rise and set:

MSL almanac

Times are UT. If you click on the google calendar button on the lower right you can add it to your own google calendar & display times in other time zones.

The data are based on the most current SPICE kernels published on http://naif.jpl.nasa.gov/naif/data_mars.html and are predictions subject to change.
Reckless
Very good and very useful.
Thanks Joe
Roy F
Tom O'Reilly
Fantastic - thank you!
Adam Hurcewicz
Very good job, Joe! Thank you !
lyford
Thanks Joe!
elakdawalla
Super!
jmknapp
Hopefully there aren't any bugs--open to suggestions for V2. Emily asked for a basic table showing the UTC for sunrise, sunset, etc. Here it is for the first 1000 sols (see attached zip file):

Click to view attachment
elakdawalla
Marvelous. Thank you!
jmknapp
QUOTE (elakdawalla @ Aug 8 2012, 10:10 PM) *
Marvelous. Thank you!


I should point out that that table reckons the start of each sol from midnight LTST (local true solar time), i.e., when the sun actually crosses the meridian. I since gather that the landed missions use LMST (local mean solar time).

From Technical Notes on Mars Solar Time

QUOTE
The Mars Science Laboratory rover project also defined Sol 0 as the solar day on which the lander would touch down. Mission controllers originally specified a mission clock based on the Local Mean Solar Time for a landing site at 137.42°E. Thus, official mission time specified the Sol 0 epoch would start at local mean midnight at 137.42°E prior to landing. However, as the landing site coordinates were later refined, after course corrections were made while MSL Curiosity was in-flight to Mars, and as the rover touched down somewhat "long" of the final target coordinates, the landing site turned out to be at 137.441635°E. Following the example of Phoenix, there was no re-definition of the MSL mission clock to match the actual landing coordinates, and so a difference of a several seconds between LMST at the landing site and mission clock resulted.


LMST diverges from LTST over the year as Mars speeds up and slows down in its eccentric orbit. The difference can be as much as 51 minutes.

Also, as I understand the practice, the local time reference is not adjusted as the rover moves, but is fixed at some "time zone" so to speak, e.g., AMT+11:00:04 for Spirit.

Maybe that table needs to be redone, as soon as I can find out for sure how JPL defines the start of each MSL sol. At least, the sunrise and sunset UTC times are accurate
mcaplinger
QUOTE (jmknapp @ Aug 9 2012, 03:45 AM) *
as soon as I can find out for sure how JPL defines the start of each MSL sol.

See ftp://naif.jpl.nasa.gov/pub/naif/MSL/kern...gc120806_v3.tsc
jmknapp
QUOTE (mcaplinger @ Aug 9 2012, 08:20 AM) *


Thanks!--didn't know that file existed.

So here's the MSL sol ephemeris recomputed using LMST:

Click to view attachment
jmknapp
It's probably more convenient to have the sun ephemeris as a web page:

http://curiositymsl.com/sundata

That table covers the nominal mission of one Mars year (668 sols).
Oersted
I´ll be the one to say it: Thanks a 1,000,000 jmknapp! The raw-image addicts in this forum will find this most helpful!
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