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Posted by: deglr6328 Apr 21 2005, 08:51 AM

I can't believe MGS is still going up there. It's as old as pathfinder!!! does anyone know where to find information on how much UDMH/MMH fuel its got left? It can't be much since there's no appreciable magnetic field around mars it can't use magnetotorquers like hubble can for reaction wheel desaturation maneuvers so it must be forced to use some fuel all the time.... I can't imagine it can last much longer. Oh and how come MGS http://tes.asu.edu/ isn't being used for global dust characterization anymore you'd think this would be a priority now that MER is on the ground....

Posted by: Analyst Apr 21 2005, 10:27 AM

From the MGS Status Report February 16, 2005:

"On 05-044 the TES spectrometer was turned on. Evaluation of this data has led to a reduced estimate of remaining life in the spectrometer lamp. Periodic turn-on of the TES spectrometer has been abandoned for the present."

http://mars.jpl.nasa.gov/mgs/status/reports/msop-mgs.html

They are using a 12 degree off nadir attitude for quite a while to reduce momentum buildup and fuel usage. AFAIK it's working fine. I dont't have any idea about the remaining fuel, but the current extension is until September 2006 (solar conjunction).

Analyst

Posted by: deglr6328 Apr 21 2005, 04:55 PM

??At first I thought HUH ?? Lamp?? Why does TES need a lamp? It's a spectrometer! But after much searching I found http://mars.jpl.nasa.gov/mgs/sci/CDsampler/document/volinfo.htm page which says "The interferometer includes a visible interferometer that is used to generate fringes which are used to control the linear drive servo and to determine position in the interferogram. This system uses two redundant neon lamps that produce an emission line at 703.2 nm for fringe generation and a continuum that is used for a quasi-white-light source for determination of zero path difference. The off-axis position of the six detectors results in self-apodization and a spectral shift that is a function of both distance from the axis and optical frequency." ohhhh now I see. After more searching I found this: photo of the lamp they used. It's just a little neon indicator lamp! They've been using the backup lamp since the original lamp failed way back in 1998! These things fail all the time in those little red switches in power strips and, well practically everywhere I see them used they inevitalbly start blinking and flickering after being used for any length of time. I bet they didn't use a DC to AC inverter to power it because of space and power issues and just used the DC power of MGS to light it instead. Using DC power on those things reduces thier life greatly for some reason.... oh well, it had a good run!

Posted by: TheChemist May 6 2005, 12:20 PM

And GOOD science at that :

http://www.msss.com/mars_images/moc/2005/05/05/index.html

Posted by: deglr6328 May 6 2005, 01:06 PM

Hmmm, I wonder if the cPROTO technique can be used with HIRISE?

Posted by: djellison May 6 2005, 03:11 PM

Hmmm, I wonder if the cPROTO technique can be used with HIRISE?

Posted by: tedstryk May 6 2005, 04:53 PM

QUOTE (deglr6328 @ May 6 2005, 01:06 PM)

Hmmm, I wonder if the cPROTO technique can be used with HIRISE?

No - it's already using a similar technique to do its observations

Doug

Posted by: edstrick May 9 2005, 01:45 AM

MGS: They are low on remaining hydrazine to desaturate the momentum wheels. The current extension may be the last or they may squeeze one more mission extension out of the fuel. They've also been able to "optimize" things for low hydrazine use.

I think I recall they intend to put the spacecraft in a "disposal" orbit some 100 km higher when they formally retire it so it won't decay anytime soon.

The spectrometer (as I gather) isn't dead. I think they're saving what remaining life it has it for special science opportunities, say the outbreak of a global dust storm or something.

Posted by: tedstryk May 9 2005, 02:23 AM

MGS:  They are low on remaining hydrazine to desaturate the momentum wheels.  The current extension may be the last or they may squeeze one more mission extension out of the fuel.  They've also been able to "optimize" things for low hydrazine use.

I think I recall they intend to put the spacecraft in a "disposal" orbit some 100 km higher when they formally retire it so it won't decay anytime soon.

The spectrometer (as I gather) isn't dead.  I think they're saving what remaining life it has it for special science opportunities, say the outbreak of a global dust storm or something.

Posted by: edstrick May 9 2005, 10:55 AM

That could well be true. Mission engineering updates that float past in public view have dwindled to zero. I don't know what could be buried on obscure mission web sites and the like.

Posted by: Analyst Jul 8 2005, 01:56 PM

From

http://mars.jpl.nasa.gov/mgs/status/reports/msop-mgs.html

"As of 05-153 (06/02/05) MGS fuel consumption is 3.3 g/day, with 9.15 kg of usable fuel remaining. At this consumption rate, the usable fuel will support operations into 2013."

Miles to go ...

Posted by: Gsnorgathon Jul 9 2005, 03:40 AM

And from the June 22 status report:

Upcoming Events:
MGS will complete 30,000 total orbits on July 9th.

That's some miles.

Posted by: deglr6328 Jul 10 2005, 08:27 PM

"As of 05-153 (06/02/05) MGS fuel consumption is 3.3 g/day, with 9.15 kg of usable fuel remaining. At this consumption rate, the usable fuel will support operations into 2013."

Miles to go ...