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djellison
Posted on: Jun 24 2010, 06:24 AM


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Internals? Doubt it. A bit of a polish to the exterior of the camera? Maybe. The wheels are certainly scuffed compared to what they were when new.
  Forum: Tech, General and Imagery · Post Preview: #161425 · Replies: 12 · Views: 14473

djellison
Posted on: Jun 23 2010, 06:27 PM


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The internet hates me.

smile.gif
  Forum: Exploration Strategy · Post Preview: #161408 · Replies: 58 · Views: 89644

djellison
Posted on: Jun 23 2010, 06:00 PM


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I was going from http://mars.jpl.nasa.gov/mro/ (bottom left corner ) - but you're right, that widget's clearly WAY out of date. Perhaps they mean 142Tb

Still - the point I was making (even the very highest downlink in planetary exploration is a LOT less than the requirements algorimancer was trying to place on a Titan aircraft.) holds true.

  Forum: Exploration Strategy · Post Preview: #161406 · Replies: 58 · Views: 89644

djellison
Posted on: Jun 23 2010, 04:16 PM


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You're not going to get 30cm resolution from orbit around Titan. Furthermore, you're not going to get 3mm resolution from an aircraft. Infact, I've never ever heard of an aircraft getting 3mm/pixel on EARTH, let alone on Titan. Google Earth imagery is mainly aerial photography, and is typically at about 25cm/pixel - maybe 12.5cm in some places. That's still a factor of 40 (1600x fewer pixels) lower than the 3mm you're suggesting. If you COULD - you wouldn't need a 10 or 100 fold increase in data return - you would need 10,000 fold increase.

Covering just 0.1% of Titan's surface at 3mm/pixel, at 8 bits per pixel, with 10:1 compression?

83,000 sqkm. At 72 Gigabits per sqkm. 5,976 TERRABITS of data.

At 30cm/pixel 0.0072 Gigabits per sqKm. 598 Gigabits.

MRO with it's huge high gain antenna, in our back-garden at Mars (compared to a flight to Titan) has sent back just 42 Gigabits of data to date.

I'm afraid your expectations are unrealistic, and your engineering suggestions are just in the wrong place in terms of complexity, feasibility etc given the budget, mass, volume etc.

If we're going to go back to Titan, I don't think AVIATR is the way to do it. The way to do it is with TSSM, so you can have the montgolfière + an orbiter for relay. You're still not going to get anywhere near your requirements. But you've going to get a lot more data, that's for sure.
  Forum: Exploration Strategy · Post Preview: #161403 · Replies: 58 · Views: 89644

djellison
Posted on: Jun 23 2010, 12:27 AM


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Neptune's orbit is 60,190 days. Uranus, 30,800. That Kepler would find an object >10,000 days is neither surprising nor unusual.
  Forum: Telescopic Observations · Post Preview: #161381 · Replies: 1264 · Views: 731478

djellison
Posted on: Jun 22 2010, 01:17 PM


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Points 2 is heading toward the area of rule 1.2. Point 10 doesn't contradict the previous statement. You can send samples to leading research institutions around the world writing the best proposals, and 10 best proposals can get samples.

Rule 1.2 is probably worth reading.
  Forum: Cometary and Asteroid Missions · Post Preview: #161358 · Replies: 258 · Views: 304493

djellison
Posted on: Jun 21 2010, 09:05 PM


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I don't think I ever tried V3 before today - so I don't know. Every QUB I had tried crashed it, including one's that worked fine in V2 and V1.

But - inexplicably - I restart my machine at lunch, and it seems to work now. Which is v good news.

That just leaves part two - the true color interpretation.
  Forum: Image Processing Techniques · Post Preview: #161344 · Replies: 30 · Views: 46624

djellison
Posted on: Jun 21 2010, 05:40 PM


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>2 year old thread time warp.

Version 1 and 2 run great on my machine. Version 3 crashes immediately. XP64 machine. Just doing a straight qub2png filename.qub without any other details. Anything I can do to help in identifying and fixing. PLUS - did that suggestion of automatically spitting out a true color image get any traction?
  Forum: Image Processing Techniques · Post Preview: #161341 · Replies: 30 · Views: 46624

djellison
Posted on: Jun 20 2010, 04:52 PM


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I would imagine the batteries last far longer than the RF link budget between DCAM and IKAROS can last.
  Forum: Private Missions · Post Preview: #161303 · Replies: 162 · Views: 218503

djellison
Posted on: Jun 20 2010, 03:18 PM


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QUOTE (nprev @ Jun 20 2010, 02:22 AM) *
Pandaneko, I'm not aware of any approved NASA sample return missions.


That's because right now, there isn't one. I think the November reference may well have been a lost-in-translation cross-over between proposed missions, and the EPOXI flyby.

  Forum: Cometary and Asteroid Missions · Post Preview: #161302 · Replies: 258 · Views: 304493

djellison
Posted on: Jun 20 2010, 05:30 AM


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QUOTE (PDP8E @ Jun 19 2010, 10:02 PM) *
Did you know that if some one shows you a random picture of either sundial from Spirit or Opportunity you can instantly tell which is which?



I've looked at every single MER image taken from Sol 1 to present sol - and I've NEVER noticed that. Good catch. I never ever stop learning stuff from this place.
  Forum: Tech, General and Imagery · Post Preview: #161289 · Replies: 12 · Views: 14473

djellison
Posted on: Jun 19 2010, 07:14 PM


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Plus, What's the November reference? The EPOXI Hartley 2 flyby?
  Forum: Cometary and Asteroid Missions · Post Preview: #161285 · Replies: 258 · Views: 304493

djellison
Posted on: Jun 19 2010, 05:57 AM


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For those wanting the soft squishy counterpart to the crunch radar targets....

Parachute testing up at the 120ft Wind Tunnel

Part 1
http://www.youtube.com/user/JPLnews#p/u/4/O7vf2HUMMdo

2
http://www.youtube.com/user/JPLnews#p/u/3/JRRcbZlofOk

3
http://www.youtube.com/user/JPLnews#p/u/2/-NJamPhtRjA

And my personal favorite - proving that Engineers are people to...Part 4
http://www.youtube.com/user/JPLnews#p/u/1/J6TceTZq1L0

The high-speed photography of chute deployment is a beautiful organic flowing rippling sea-creature like event that is worth watching on its own. Stunning.
  Forum: MSL · Post Preview: #161272 · Replies: 414 · Views: 203792

djellison
Posted on: Jun 15 2010, 01:16 PM


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OK, I'll have a go. As it was approaching the earth, it's motion was, from that frame of reference, slower than the rotation of the earth. Therefore, with respect to the earths s surface, it was moving west. As it accelerated, it first matched the rotation of the earth (traveling about as fast as a geostationary satellite) and then continued to accelerate so it was going faster than the rotation of the earth and appeared to move east.

In reality, it's velocity was always faster than that diagram infers, but by projecting it down into a ground track we are dramatically foreshortening a trajectory at basically aimed 10 degrees in from the edge of the Earth.

If it had missed the Earth that diagram would be similar, continue going East, and then as it got further away again, stop and move west again.

It's not to do with the atmosphere - it only hits the atmosphere at the last tiny segment of that diagram.
  Forum: Cometary and Asteroid Missions · Post Preview: #161118 · Replies: 702 · Views: 694438

djellison
Posted on: Jun 14 2010, 03:18 PM


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HGAS?
  Forum: MSL · Post Preview: #161058 · Replies: 414 · Views: 203792

djellison
Posted on: Jun 13 2010, 12:05 AM


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Oh - I don't think they've overlanded a spacecraft in years have they? Bound to be an airlift.

  Forum: MSL · Post Preview: #160905 · Replies: 414 · Views: 203792

djellison
Posted on: Jun 11 2010, 12:57 AM


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LOLA is nothing to do with LCROSS.
  Forum: LRO & LCROSS · Post Preview: #160831 · Replies: 12 · Views: 32739

djellison
Posted on: Jun 7 2010, 03:23 AM


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That's probably the seam between two of the 10 ccd's that make up a B&W HiRISE swath
  Forum: Opportunity · Post Preview: #160710 · Replies: 741 · Views: 457343

djellison
Posted on: Jun 4 2010, 07:03 PM


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A great day - period. Turn around from an on-pad abort to LEO in 90 minutes. Awesome.
  Forum: Private Missions · Post Preview: #160567 · Replies: 240 · Views: 2300169

djellison
Posted on: Jun 4 2010, 06:31 PM


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Countdown restarted at T-15m so 11:45PST T-0.
  Forum: Private Missions · Post Preview: #160559 · Replies: 240 · Views: 2300169

djellison
Posted on: Jun 4 2010, 06:20 PM


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Just to correct BrianL's choice of words there - it's not Pancam that's being tested here. Or Navcam even. It's the mechanism that points them. And whatever happens to it, we still have Hazcams.
  Forum: Opportunity · Post Preview: #160558 · Replies: 45 · Views: 44421

djellison
Posted on: Jun 4 2010, 06:19 PM


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Demoflight 2 went from a t-0.5s abort, to a launch, in 70 minutes.
  Forum: Private Missions · Post Preview: #160557 · Replies: 240 · Views: 2300169

djellison
Posted on: May 28 2010, 01:58 PM


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Probably in the 500-1000 kwhr range I'd have thought. Ish.
  Forum: Opportunity · Post Preview: #160295 · Replies: 24 · Views: 27858

djellison
Posted on: May 27 2010, 06:20 AM


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That's been asked a thousand times. Go look at your TV. It's vertical, right... but the screen's still dusty. tilting them vertical is probably not going to do much.

Plus - such a mechanism has it's own failure modes, complexities and risks. A dirty solar array is far far better than one that's stuck vertical.
  Forum: Opportunity · Post Preview: #160240 · Replies: 24 · Views: 27858

djellison
Posted on: May 27 2010, 05:44 AM


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Beagle 2, to, had a spin up and eject mechanism ( the SUEM ) that basically was spring loaded, but when released, it pushed through a spiral form to impart spin as it went.
  Forum: Cometary and Asteroid Missions · Post Preview: #160238 · Replies: 702 · Views: 694438

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