KBO encounters |
KBO encounters |
Apr 15 2010, 09:32 AM
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#31
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Merciless Robot Group: Admin Posts: 8789 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Actually, Alan said in this post that the search won't start till next year.
-------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Apr 15 2010, 12:18 PM
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#32
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Member Group: Members Posts: 532 Joined: 19-February 05 Member No.: 173 |
The first post in this thread says the search would start in 2010 - has it started yet, or will it be later this year? Our best imager, LORRI, can resolve the size of an object from roughly 10^5 object diameters away. So for a 100 km object, for example, we have to be w/i 10^7 km just to resolved it; if you want crude shape information, cut that to 10^6 diameters, and if you want "geology," well, better come to approx 30,000 diameters or better. The point here is Crantor and other distant flybys don't yield much of use, so we have not expended effort on them. As to our KBO search, John Spencer is leading the organizational effort to recruit search teams; Andrew Steffl is helping John. Our plan is to conduct the search in 2011 and 2012, though Scott Shepard at least has already begun. -Alan |
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Apr 15 2010, 04:58 PM
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#33
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
Yeah, I think the last few times we've asked this question (maybe we need an FAQ section for each long-term mission) the answer was "not until we're past the orbit of Uranus."
--Greg |
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Apr 27 2010, 06:11 PM
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#34
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Junior Member Group: Members Posts: 24 Joined: 29-May 08 From: Seattle, USA Member No.: 4162 |
Our best imager, LORRI, can resolve the size of an object from roughly 10^5 object diameters away. So for a 100 km object, for example, we have to be w/i 10^7 km just to resolved it; if you want crude shape information, cut that to 10^6 diameters, and if you want "geology," well, better come to approx 30,000 diameters or better. Alan, thanks for the info, but I'm a little confused... I assume that for crude shape information, you mean cut the maximum distance to 106 kilometers, since 106 diameters would be 108 kilometers. But which do you mean for the "geology" figure? 30,000 diameters would be 3 million kilometers for our theoretical 100 km object, which is tough enough, but 30,000 kilometers is more or less a bullseye: better targeting than even Apophis will manage . It seems to me you could get at least some worthwhile surface-feature resolution at a greater distance than that. The famous LORRI images of Tvashtar's plume resolved fine details at 2.5 million km. On the other hand, I know that spacecraft (and ground) resources are limited, and you have to be sure you're getting enough meaningful data for any expenditure. Could you give any hints as to when you think it might be worthwhile to observe during one of these flybys? |
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Apr 28 2010, 05:55 PM
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#35
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Member Group: Members Posts: 259 Joined: 23-January 05 From: Seattle, WA Member No.: 156 |
The Tvashtar plume images were taken a lot closer to the sun than any KBO images will be. I imagine blurring due to longer exposure times would reduce resolution at comparable distances.
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Apr 28 2010, 07:36 PM
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#36
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Member Group: Members Posts: 717 Joined: 3-December 04 From: Boulder, Colorado, USA Member No.: 117 |
I'll chip in here. Alan was talking about science at Centaurs that we might fly past on our way to Pluto- none of those will get close enough to be resolved. For the KBO target(s) beyond Pluto, we will deliberately target to get within a few tens of thousands of kilometers or closer- from 20,000 km, for instance, we would get 500 pixels across a 50 km KBO- sufficient to do some serious geology. LORRI can get well-exposed, unsmeared, images at Pluto's distance from the sun (it was designed to do that, of course), and while illumination conditions will be more challenging further out in the Kuiper Belt, there's enough performance margin that we expect to be able to do the same there.
At Crantor's distance, a LORRI pixel is 2000 km across, much bigger than Crantor itself. So there's no hope of getting any shape information. And to make sure no-one is still confused on this point, we will not be searching for KBOs with NH itself- huge ground-based telescopes with wide-field imagers can do that much better, even though they're stuck at 1 AU. John |
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Feb 22 2011, 10:55 PM
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#37
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Member Group: Members Posts: 717 Joined: 3-December 04 From: Boulder, Colorado, USA Member No.: 117 |
Talking of KBOs, here's a heads-up that YOU can probably help us to find Kuiper Belt objects for New Horizons to fly by after Pluto, starting in a month or two. We're working with the Zooniverse folks to set up a "KBO Zoo" where you will be able to help us identify moving objects (i.e. potential KBOs) in the Milky Way star fields that we'll be imaging with the Subaru, Magellan, and Canada-France-Hawaii telescopes this summer. Details once the site is up and running.
John |
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Feb 22 2011, 11:01 PM
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#38
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Senior Member Group: Admin Posts: 3108 Joined: 21-December 05 From: Canberra, Australia Member No.: 615 |
If we find it, can we name it?! I always thought that "Astro0's Orb" had a nice ring to it!
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Feb 22 2011, 11:54 PM
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#39
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Senior Member Group: Members Posts: 1598 Joined: 14-October 05 From: Vermont Member No.: 530 |
We're working with the Zooniverse folks to set up a "KBO Zoo" where you will be able to help us identify moving objects (i.e. potential KBOs) in the Milky Way star fields that we'll be imaging Sweet! |
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Feb 23 2011, 01:10 AM
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#40
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Merciless Robot Group: Admin Posts: 8789 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
THAT is a rockin' piece of citizen science outreach, John! Very much looking forward to it!
-------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Feb 23 2011, 02:54 PM
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#41
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Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
John,
That's great news, can't wait to participate in the search for targets! -------------------- Space Enthusiast Richard Hendricks
-- "The engineers, as usual, made a tremendous fuss. Again as usual, they did the job in half the time they had dismissed as being absolutely impossible." --Rescue Party, Arthur C Clarke Mother Nature is the final inspector of all quality. |
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Apr 20 2011, 02:59 PM
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#42
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Forum Contributor Group: Members Posts: 1374 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
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Apr 20 2011, 03:17 PM
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#43
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Member Group: Members Posts: 717 Joined: 3-December 04 From: Boulder, Colorado, USA Member No.: 117 |
Look for another release in a few weeks, describing how you can help us sift through all those images.
John |
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Apr 20 2011, 03:47 PM
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#44
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Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Look for another release in a few weeks, describing how you can help us sift through all those images. Great, I cannot wait!!! -------------------- I always think before posting! - Marco -
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May 8 2011, 03:12 AM
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#45
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Member Group: Members Posts: 204 Joined: 29-June 05 Member No.: 421 |
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