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Del Palmer
Posted on: Dec 23 2007, 07:24 AM


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QUOTE (nprev @ Dec 23 2007, 02:05 AM) *
Are they ring-laser gyro IMUs, or are they mechanical?


The MERs use the popular LN-200 IMU. Full specs here:

http://www.nsd.es.northropgrumman.com/Auto...cts/LN-200.html
  Forum: Mars · Post Preview: #106208 · Replies: 186 · Views: 141716

Del Palmer
Posted on: Dec 18 2007, 04:43 AM


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The flyby mission description is now up.
  Forum: Titan · Post Preview: #105854 · Replies: 57 · Views: 57201

Del Palmer
Posted on: Dec 15 2007, 02:24 AM


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QUOTE (SpaceListener @ Dec 13 2007, 09:58 PM) *
Let see what technology would be winner: Solar panel or Fuel Cells.


You need both. A fuel cell is like a battery: it just stores energy. It would be useless without solar cells to 'charge' it up.
  Forum: Lunar Exploration · Post Preview: #105696 · Replies: 12 · Views: 13880

Del Palmer
Posted on: Dec 10 2007, 10:44 PM


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Gene Cernan said Moondust smelled like burnt gunpowder. Jim Garvin has said that Mars would have a similar odor to volcanic areas on Earth (sulfur-rich).
  Forum: Spirit · Post Preview: #105449 · Replies: 429 · Views: 278369

Del Palmer
Posted on: Dec 10 2007, 08:29 PM


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QUOTE (Sunspot @ Dec 10 2007, 07:55 PM) *
Isn't there a big Apple conference next month? I might see what happens there.


Yup: MacWorld, Jan 15th. Usually new hardware introduced, so it would be wise to wait, just in case. smile.gif WinME? ohmy.gif That machine would be a lot better with Windows 2000 or XP.
  Forum: Chit Chat · Post Preview: #105443 · Replies: 20 · Views: 17286

Del Palmer
Posted on: Dec 10 2007, 05:47 PM


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I owned one from June 07 to last week (only just sold it on eBay) to run some Mac-only software. I also had the intention of replacing my ancient PC and reduce my carbon footprint (Mac Mini power consumption = 23 W/Hr versus 72 W/Hr (idle) for the PC). However, the more I used the Mac, the more I found fault with the OS. In other words, matters of personal preference can be deal-breakers, and I would strongly recommend that you try out Mac OS X before buying...
  Forum: Chit Chat · Post Preview: #105437 · Replies: 20 · Views: 17286

Del Palmer
Posted on: Dec 6 2007, 02:55 AM


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Ah, memories. smile.gif

http://web.archive.org/web/19970605230559/...//www.nasa.gov/

The NASA HQ portal 10 years ago. How it has changed! Loved the patterned background; reminds me of my first website (made using Microsoft FrontPage (ugh)) back in 1998. smile.gif
  Forum: Chit Chat · Post Preview: #105134 · Replies: 3 · Views: 4838

Del Palmer
Posted on: Dec 6 2007, 02:41 AM


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QUOTE (SkyeLab @ Dec 5 2007, 03:08 PM) *
It seems pretty slick to me but could be problematic for those on dial-up connections.


It might also be problematic for those with slow computers. wink.gif The site loaded quickly over an 8 Mbps connection, but then my browser was unresponsive for 12 seconds while it processed all of that lovely javascript stuff. Yet another site to put in the 'Restricted sites zone' to block javascript (sigh). Fortunately, I rarely visit the HQ portal, but if the other centers adopt this then it may finally motivate me to get a faster machine...
  Forum: Chit Chat · Post Preview: #105132 · Replies: 3 · Views: 4838

Del Palmer
Posted on: Dec 4 2007, 03:27 PM


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The Lyot Project coronagraph to be installed at Palomar:

http://planetquest.jpl.nasa.gov/news/lyotNews.cfm
  Forum: Telescopic Observations · Post Preview: #105024 · Replies: 26 · Views: 25212

Del Palmer
Posted on: Dec 3 2007, 01:46 AM


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QUOTE (stevesliva @ Oct 4 2007, 11:02 PM) *
how long does Spitzer have before it starts warming up?


Latest estimate for helium depletion is March 2009.
  Forum: Telescopic Observations · Post Preview: #104959 · Replies: 6 · Views: 7855

Del Palmer
Posted on: Nov 28 2007, 04:24 AM


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The flyby mission description is now up.

1,300 km altitude, southern hemisphere, outbound. ISS and VIMS will observe Ontario Lacus. smile.gif
  Forum: Titan · Post Preview: #104707 · Replies: 21 · Views: 18935

Del Palmer
Posted on: Nov 27 2007, 05:34 PM


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CRISM captures Phobos and Deimos:

http://crism.jhuapl.edu/gallery/featuredIm...amp;image_id=98

QUOTE
These CRISM measurements are the first spectral measurements to resolve the disk of Deimos, and the first of this part of Phobos to cover the full wavelength range needed to assess the presence of iron-, water-, and carbon-containing minerals.


Looks like the page has a broken image; the image is here.
  Forum: MRO 2005 · Post Preview: #104673 · Replies: 86 · Views: 164706

Del Palmer
Posted on: Nov 22 2007, 11:20 PM


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QUOTE (nprev @ Nov 22 2007, 10:42 PM) *
Yeah, I knew that; wasn't the guy who found that Italian?


Gary Flandro. Not sure if he was Italian or not (thought he was American).
  Forum: Jupiter · Post Preview: #104458 · Replies: 304 · Views: 223647

Del Palmer
Posted on: Nov 20 2007, 10:02 PM


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Speaking of young planetary systems and Spitzer:
http://www.spitzer.caltech.edu/Media/relea...8/release.shtml

QUOTE
Gorlova and her colleagues looked for the dusty signs of similar smash-ups around 400 stars that are all about 30 million years old - roughly the age of our sun when Earth's moon formed. They found that only 1 out of the 400 stars is immersed in the telltale dust. Taking into consideration the amount of time the dust should stick around, and the age range at which moon-forming collisions can occur, the scientists then calculated the probability of a solar system making a moon like Earth's to be at most 5 to 10 percent.
  Forum: Telescopic Observations · Post Preview: #104326 · Replies: 4 · Views: 5768

Del Palmer
Posted on: Nov 19 2007, 05:09 PM


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Regarding frozen orbits, I couldn't find the original paper, but here's an article that is derived from it.
  Forum: Lunar Exploration · Post Preview: #104178 · Replies: 502 · Views: 634783

Del Palmer
Posted on: Nov 19 2007, 12:46 PM


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QUOTE (edstrick @ Nov 19 2007, 02:55 AM) *
You simply need to design a vehicle that will do an orbit trim maneuver or two every orbit. Just a 1/2 km tweek... just keep it circular within a small amount.


I remember reading an AIAA paper that suggested "frozen orbits" exist at low altitude, with a caveat that the orbit's inclination matters significantly. It concluded that at certain inclinations (27º, 50º, 76º, and 86º) it is possible for a spacecraft to remain in a low-lunar orbit indefinitely, without OTMs.
  Forum: Lunar Exploration · Post Preview: #104155 · Replies: 502 · Views: 634783

Del Palmer
Posted on: Nov 16 2007, 10:59 PM


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Would a modified version of LEMUR be up to the job?
  Forum: Past and Future · Post Preview: #104057 · Replies: 34 · Views: 38073

Del Palmer
Posted on: Nov 15 2007, 01:08 AM


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Yes, sorry I wasn't clearer. W = Watt-hours per sol.
  Forum: Spirit · Post Preview: #103949 · Replies: 429 · Views: 278369

Del Palmer
Posted on: Nov 14 2007, 11:51 PM


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QUOTE (Aussie @ Nov 14 2007, 11:09 PM) *
Since the heaters cut in last winter there is a high probability that they will do so again. Anyone have any knowledge as to the power draw for these heaters?


According to the MER thermal design document at JPL's reference archive, the MiniTES survival heater would consume 55 W on a cold night. Of course, Spirit could opt to use Deep Sleep to avoid survival heater usage at night. During the day, the WEB survival heaters use 60 W, so you'd want to avoid those from kicking in by running the computer for longer periods, as was done on Oppy.
  Forum: Spirit · Post Preview: #103945 · Replies: 429 · Views: 278369

Del Palmer
Posted on: Nov 14 2007, 11:21 PM


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QUOTE (Mariner9 @ Nov 14 2007, 07:07 PM) *
As for array deployment problems, I don't think it is a good apples to apples comparison to bring up the ISS troubles. Those arrays are huge, and involve a huge number of folds.


Hubble's SA1 arrays were much smaller than the ISS arrays, yet the astronauts had to toss one overboard when it failed to retract...
  Forum: Juno · Post Preview: #103943 · Replies: 597 · Views: 607294

Del Palmer
Posted on: Nov 14 2007, 09:32 PM


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The mission flyby description is now up.

1,000 km altitude, southern hemisphere, high-phase angle inbound (Titan backlit by the Sun).
  Forum: Titan · Post Preview: #103934 · Replies: 6 · Views: 7161

Del Palmer
Posted on: Nov 13 2007, 11:23 PM


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Flyby successful!

http://webservices.esa.int/page.php
  Forum: Cometary and Asteroid Missions · Post Preview: #103835 · Replies: 65 · Views: 65211

Del Palmer
Posted on: Nov 12 2007, 10:11 PM


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There may still be unfired pyro valves in the propulsion system, which are used to isolate or pressurize parts of the system.
  Forum: Voyager and Pioneer · Post Preview: #103746 · Replies: 3 · Views: 9666

Del Palmer
Posted on: Nov 12 2007, 09:31 PM


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QUOTE (Arnaud @ Nov 12 2007, 08:16 PM) *
I had seen the thread, but didn't advance enough in reading it to notice the transmission curves of the Galileo. On the internet, I read that the Galileo SSI is really a modified Voyager camera with similar filters.


Only the telescope and filters are similar. Galileo used a CCD in contrast to Voyager's videcon tube.
  Forum: Venus · Post Preview: #103743 · Replies: 5 · Views: 11531

Del Palmer
Posted on: Nov 12 2007, 04:33 PM


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Goddard have unveiled a new antenna farm at White Sands that will support LRO:

http://www.nasa.gov/centers/goddard/news/t...07/ka-band.html

The antennas use glue instead of bolts! The future of the DSN? wink.gif
  Forum: LRO & LCROSS · Post Preview: #103704 · Replies: 175 · Views: 266749

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