EPOXI Mission News |
EPOXI Mission News |
May 28 2008, 07:48 PM
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#1
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Senior Member Group: Members Posts: 1585 Joined: 14-October 05 From: Vermont Member No.: 530 |
Looks like the Deep Impact list has been revived. Posting here for others to get back on board:
********************************************************************** EPOXI E-News #1 May 2008 ********************************************************************** WELCOME BACK! Did you know that the Deep Impact Flyby Spacecraft has a new assignment? The EPOXI mission combines two exciting science investigations in an entirely new mission that re-uses the Deep Impact spacecraft. The Extrasolar Planet Observation and Characterization (EPOCh) investigation will observe stars that have known transiting giant planets. The Deep Impact Extended Investigation (DIXI) of comets observes comet 103P/Hartley 2 during a close flyby in October 2010. The education and public outreach team decided to get back in touch with our Deep Impact friends and begin sending out newsletters again to keep you informed of these two exciting investigations! During the two years since our last newsletter for Deep Impact, the science team has stayed busy continuing to do more analysis on the data collected in July 2005. The science team also proposed and was awarded an extended mission teaming up with a group from Goddard Space Flight Center. EPOXI website: http://epoxi.umd.edu/ Mission Overview: http://epoxi.umd.edu/1mission/index.shtml Press Releases: http://epoxi.umd.edu/7press/index.shtml DI Results: http://deepimpact.umd.edu/results/ ********************************************************************** MISSION STATUS Dr. Deming, Principal Investigator (PI) for the EPOCh portion of the mission, sends us the latest mission status report in which he tells us about the current observing target GJ436. “This is an exciting time for EPOCh, as we search for an exo-Earth orbiting a stellar neighbor of our Sun!” reports Dr Deming. He also talks about the plans to observe a very special planet in late May and early June. Read his status report as well as past reports from other team members at http://epoxi.umd.edu/1mission/status.shtml ********************************************************************** EPOCh TARGETS The EPOCh component of the EPOXI mission will carefully study a small number of stars in order to learn more about planets that we know are orbiting those stars by watching the planets as they transit (cross in front of) the star. EPOCh will also search for clues to other planets that might be orbiting the same stars. Read more about the EPOCh science targets to find out which stars are being observed. http://epoxi.umd.edu/2science/targets.shtml ********************************************************************** PLANET QUEST Are we alone? For centuries, human beings have pondered this question. Medieval scholars speculated that other worlds must exist and that some would harbor other forms of life. In our time, advances in science and technology have brought us to the threshold of finding an answer to this timeless question. The recent discovery of numerous planets around stars other than the sun confirms that our solar system is not unique. Indeed, these "exoplanets" appear to be common in our galactic neighborhood. The EPOCh investigation is part of a larger family of missions studying extrasolar planets. Learn more at the Jet Propulsion Lab Planet Quest Web site. http://planetquest.jpl.nasa.gov/index.cfm ********************************************************************** OBSERVING CHALLENGE The transits that will be studied for EPOCh are extremely difficult to observe because the change in brightness is very small and requires high precision photometry that can be accomplished with instruments on the Deep Impact spacecraft. Observers on Earth can still take a look at the stars in the night time sky. The selected stars are also pretty dim because we don’t want them to saturate or over expose the spacecraft instruments but they are bright enough to be visible in amateur telescopes if the sky conditions are good and the skies are dark. Like people, stars have multiple identifiers. EPOCh’s first target was a star labeled as HAT-P-4 by the scientists observing it. They made their own list of target stars so that was their shorthand name. But HAT-P-4 has numerous other names which are more useful in identifying it in other databases. HAT-P-4 = SAO 64638 = TYC 2569-1599-1 is a magnitude 11, G-class star located in the constellation Boötes. Chart: http://epoxi.umd.edu/2science/challenge.shtml ********************************************************************** SUBSCRIPTION INFORMATION Please forward this e-mail to others interested in NASA missions. New subscribers may join the EPOXI Mission e-news mailing list on our website at: http://epoxi.umd.edu/6outreach/newsletter.shtml |
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Jun 3 2008, 07:31 PM
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Member Group: Members Posts: 118 Joined: 18-November 07 Member No.: 3964 |
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Jun 4 2008, 12:37 AM
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Interplanetary Dumpster Diver Group: Admin Posts: 4404 Joined: 17-February 04 From: Powell, TN Member No.: 33 |
Wow, it got a beautiful shot. I can't wait for the raw data release.
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Jun 4 2008, 10:48 AM
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Member Group: Members Posts: 146 Joined: 23-August 06 From: Vriezenveen, Netherlands Member No.: 1067 |
Here's a simulated view:
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Jul 4 2008, 04:40 PM
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Interplanetary Dumpster Diver Group: Admin Posts: 4404 Joined: 17-February 04 From: Powell, TN Member No.: 33 |
I still can't wait for the raw data. There really is a lot of data in the images. For example, here is a cleanup of a view of the moon from shortly after launch.
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Jul 4 2008, 06:43 PM
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Interplanetary Dumpster Diver Group: Admin Posts: 4404 Joined: 17-February 04 From: Powell, TN Member No.: 33 |
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Jul 19 2008, 07:50 AM
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#7
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
Two papers about EPOXI published yesterday by arxiv:
The NASA EPOXI mission of opportunity to gather ultraprecise photometry of known transiting exoplanets Preliminary Results on HAT-P-4, TrES-3, XO-2, and GJ 436 from the NASA EPOXI Mission |
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Mar 19 2009, 08:46 PM
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#8
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
As a member of the EPOXI flight team, I am astonished that this data has been made public yet. The EPOCh portion of EPOXI finished 8/31/08 (photometry of transiting hot-jupiters and observing Earth as an exo-planet analog). The science team has had over 7 months to analyze the data and the only thing made public is the lunar transit animation. Granted, that's pretty sweet, but you'd think they would release some more data.
I met Doug (UMSF founder) on Tuesday (3/17) when he was here at JPL. I'm impressed with what you all are doing on the site with MER data, among the other missions. I'd love to see UMSF participate real-time with the Hartley-2 flyby similar to the DI prime mission flyby of Tempel-1. Let me talk with our Public Outreach people and our science team and I'll see if I can get any data released to the "world". What exactly would you guys want? .jpgs? raw binary images? Please let me know and I'll see if I can get any data released. Many thanks and keep up the great work! I always like to see people excited about EPOXI when most people at JPL don't even know we exist! ~Rich p.s. we just published a paper on how we did the EPOCh observations at the 2009 IEEE Aerospace Conference. I'm not sure if the paper is available to the public free-of-charge, but I'll see if I can get a copy of the paper and presentation out... |
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Mar 19 2009, 08:50 PM
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#9
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
Let me talk with our Public Outreach people and our science team and I'll see if I can get any data released to the "world". What exactly would you guys want? .jpgs? raw binary images? Please let me know and I'll see if I can get any data released. I'm waiting for the lunar transit images myself. I read the archival plan document which stated EPOCh data was supposed to be delivered to PDS back in October so I was expecting the peer review and release to come in January. It's now March and still no luck. Is there perhaps a delivery planned for April or is it postponed indefinitely? -------------------- |
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Mar 19 2009, 08:55 PM
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#10
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
Welcome aboard Rich, good to have you here! Anything you can drop into our eager little hands will be greatly appreciated!
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Mar 19 2009, 10:12 PM
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#11
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Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
Let me talk with our Public Outreach people and our science team and I'll see if I can get any data released to the "world". What exactly would you guys want? .jpgs? raw binary images? Please let me know and I'll see if I can get any data released. Of course image processing mavens dislike JPEGs because of the compression artifacts, but raw binaries are inaccessible except to a few people with the technical knowledge necessary to open them. A good compromise is PNG, which most browsers display just as easily as JPEG (so it's accessible to the less-skilled) but which don't suffer from compression artifacts. (PNGs can also be 16-bit, while JPEGs max out at 8 bits per channel. I haven't looked into the DI camera system lately so I don't recall what bit depth it's capable of and don't know whether that matters.) On top of that, metadata for each image is valuable, starting with the simplest stuff like date/time of the observation, target, and filter choices. Some of the more skilled people here will gladly ingest whatever metadata you can get away with releasing -- either as detached headers for each image, or just one text file containing the data for all the images, like you get with the PDS INDEX.TAB files, will make people here jump for joy. --Emily -------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
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Mar 20 2009, 12:35 AM
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#12
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
Let me talk with our Public Outreach people and our science team and I'll see if I can get any data released to the "world". What exactly would you guys want? .jpgs? raw binary images? Please let me know and I'll see if I can get any data released. Hello Rich, welcome to UMSF. I am running realtime simulations for current interplanetary spacemissions, including EPOXI, so I am greatly interested in up-to-date SPICE kernels to extract trajectory data (spk_od224_NoBurn-full.bsp is the current file, right?) and/or in up-to-date Horizons data (which seems to be there). I also include a mission timeline, so I am very keen on any mission events (TCM's, particular observations, etc) that I can include in the timeline, preferably in advance of them happening. I have noted that EPOXI is not on the Solar System Simulator (http://space.jpl.nasa.gov/) ... Deep Impact is but gives an error if you enter today's date ... which I think would be a good tool to have (both for the general public and to incorporate images into my simulations). So maybe you could suggest to the team at the Solar System Simulator to have EPOXI enabled :-) Good luck with your mission! -------------------- |
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Mar 23 2009, 05:11 PM
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#13
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
Daniel, the SPICE kernel you have is slightly out of date. Your version was generated before TCM-14 without the TCM-14 burn. You want to be using spk_drm224_Burn-full.bin That's the latest and greatest o.d. solution. Where are you getting these by the way? Are they public?
I sent an e-mail to the webmaster for space.jpl.nasa.gov and asked him to add EPOXI. He hasn't gotten back to me, but I hope we'll get EPOXI in there. I talked to the P.I. about getting EPOCh images released to the public. They're thought is, "why should we release them is no one will want to look at them because they're ugly, fuzzy images, especially in .jpg format." The data should be published to the PDS next month and made public about a month after. So, images around May perhaps... don't hold your breath. Oh, and we're going to do another Earth observation of the North pole on Friday 3/27/09. It should give us some more pretty pictures ~Rich |
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Mar 23 2009, 06:49 PM
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#14
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
p.s. we just published a paper on how we did the EPOCh observations at the 2009 IEEE Aerospace Conference. I'm not sure if the paper is available to the public free-of-charge, but I'll see if I can get a copy of the paper and presentation out... I would definitely be interested in seeing it! |
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Mar 23 2009, 08:27 PM
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#15
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
I would definitely be interested in seeing it! I called the ethics office on Thursday. I don't know the legalities of posting it here. I think I can get the presentation here, but I'm not sure about the paper. I'll get them up as soon as I know if it's legal. The paper is entitled "The Contingency of Success: Deep Impact's Planet Hunt" published at the 2009 IEEE Aerospace Conference in Big Sky, MT if you want to search for it. If you find a url to it, be sure to post it here. ~Rich |
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Mar 23 2009, 09:52 PM
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#16
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
So I just got a blessing from the Ethics office. Attached is the presentation on EPOCh observations I gave at the IEEE conference in Big Sky. Feel free to bug me with questions. I'm continuing to research the legal aspects of posting the paper here too. Stay tuned!
EPOCh_IEEE_Presentation_umsf.pdf ( 963.67K ) Number of downloads: 907 ~Rich |
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Mar 24 2009, 12:35 AM
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#17
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
Dear Rich,
Daniel, the SPICE kernel you have is slightly out of date. Your version was generated before TCM-14 without the TCM-14 burn. You want to be using spk_drm224_Burn-full.bin That's the latest and greatest o.d. solution. Thanks so much for the clarification. I will incorporate the file into the next data update. Where are you getting these by the way? Are they public? Yes the SPICE kernels are public and for most missions they can be found at http://naif.jpl.nasa.gov/naif/ EPOXI, still under the Deep Impact name, is listed under the Comet and Asteroid missions at http://naif.jpl.nasa.gov/naif/data_comet.html The Horizons system at http://ssd.jpl.nasa.gov/?horizons also runs on SPICE kernels but occasionally it is not updated. At the moment it seems to use CODE Trajectory Name Start UTC Stop UTC ----------------------------- -------------------- -------------------- [...] drm220_withTCM12-full 2008 APR 18 09:00:00 2008 DEC 09 00:00:00 (103P/Hartley 2 soln.: #49) drm223_with_tcms-full 2008 DEC 09 00:00:00 2012 JAN 31 00:00:00 epoxi_2008-2019.090217 2012 JAN 31 00:00:00 2019 JAN 01 00:00:00 I sent an e-mail to the webmaster for space.jpl.nasa.gov and asked him to add EPOXI. He hasn't gotten back to me, but I hope we'll get EPOXI in there. Thanks. If you wish to include timeline events, feel free to send them to me and I'll upload them in due course. Anything to create a grain of outreach for your mission :-) -------------------- |
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Mar 25 2009, 12:03 AM
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#18
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IMG to PNG GOD Group: Moderator Posts: 2251 Joined: 19-February 04 From: Near fire and ice Member No.: 38 |
Let me talk with our Public Outreach people and our science team and I'll see if I can get any data released to the "world". What exactly would you guys want? .jpgs? raw binary images? Please let me know and I'll see if I can get any data released. I myself prefer PDS formatted data and there are probably lots of people here that also prefer it but PNGs are better known and are probably the best option to make the data easier to use for lots of people. As previously discussed, PNGs are far better than JPGs due to the absence of compression artifacts and the fact that they can be 16 bits/pixel when needed. Their only drawback compared to JPGs is bigger files. |
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Mar 25 2009, 08:43 PM
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#19
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
I myself prefer PDS formatted data and there are probably lots of people here that also prefer it but PNGs are better known and are probably the best option to make the data easier to use for lots of people. As previously discussed, PNGs are far better than JPGs due to the absence of compression artifacts and the fact that they can be 16 bits/pixel when needed. Their only drawback compared to JPGs is bigger files. Sorry Bjorn. I don't think the project will release any EPOXI data to the PDS until April and it may not get released to the public until May. You'll have to stay perched on the edge of your computer chair until then. I'll see if I can get anything released to the world, but you may have to settle for .jpgs. Sorry! .jpgs are better than nothing! ~Rich |
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Mar 27 2009, 12:15 AM
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#20
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
Mission update:
FYI, we will be taking more pictures of the Earth tomorrow in a similar fashion to how the previous Earth observations were performed (in fact, we're using the exact same sequences, fancy that). However, we will be significantly closer than the Earth Observation that took the lunar transit movie (17 Gm compared to 50 Gm (that's giga-meters, or Mkm (that's Mega-kilometers) (and yes, that's a subnested parenthetic remark)). Since the spacecraft is now north of the ecliptic plane, we will be looking down on the Earth's north pole. A simulated image of what we might see has been floating around JPL. I'll ask around to see if I can post it. Images will be coming down Saturday. ~Rich |
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Mar 27 2009, 12:49 AM
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#21
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Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
Sweet. Can't wait to see the pics. --Emily
-------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
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Mar 30 2009, 10:21 PM
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#22
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
I have noted that EPOXI is not on the Solar System Simulator (http://space.jpl.nasa.gov/) ... Deep Impact is but gives an error if you enter today's date ... which I think would be a good tool to have (both for the general public and to incorporate images into my simulations). So maybe you could suggest to the team at the Solar System Simulator to have EPOXI enabled :-) Good luck with your mission! dmueller: It's amazing what a simple e-mail does EPOXI is now in the JPL Solar System Simulator! Thanks for pointing that out to us. In other news, the images from this weekend's Earth Observation are now on the ground and they look great! |
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Mar 31 2009, 02:51 AM
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#23
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
dmueller: It's amazing what a simple e-mail does EPOXI is now in the JPL Solar System Simulator! Thanks for pointing that out to us. Thanks for asking, Rich! Have updated the EPOXI Realtime Simulation accordingly. Incidentally I figured out how to make my website tweet to my Twitter. In due course I hope to get it to periodically tweet mission updates onto my Twitter. Standby. -------------------- |
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Mar 31 2009, 11:27 PM
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#24
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
Hi all,
I just noticed a new article on the EPOXI website by the EPOCh P.I. Drake Deming: http://epoxi.umd.edu/2science/alienmaps.shtml Enjoy! ~Rich |
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Apr 1 2009, 07:40 PM
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#25
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
I just noticed a new article on the EPOXI website by the EPOCh P.I. Drake Deming: There was a presentation on the same subject here: http://www.astro.washington.edu/users/cowa..._lunch_talk.ppt but it has been removed. It is cached on Google in html http://209.85.129.132/search?q=cache:wdXK3..._lunch_talk.ppt |
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Apr 4 2009, 06:55 AM
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#26
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
Incidentally I figured out how to make my website tweet to my Twitter. In due course I hope to get it to periodically tweet mission updates onto my Twitter. Standby. Selected trajectory information about some missions (including EPOXI) are now tweeting automatically to my Twitter account about once every day -------------------- |
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Apr 7 2009, 04:44 PM
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#27
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
There was a presentation on the same subject here: http://www.astro.washington.edu/users/cowa..._lunch_talk.ppt but it has been removed. It is cached on Google in html http://209.85.129.132/search?q=cache:wdXK3..._lunch_talk.ppt Paolo: I can't seem to find those presentations. You don't have a copy of them do you? ~Rich |
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Apr 7 2009, 07:26 PM
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#28
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
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Apr 10 2009, 06:40 PM
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#29
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Interplanetary Dumpster Diver Group: Admin Posts: 4404 Joined: 17-February 04 From: Powell, TN Member No.: 33 |
FYI, Hubble is presently studying Hartley-2 to try to pin down the basic properties of the nucleus, especially the rotation period, so that the information can be incorporated into mission planning.
http://www.stsci.edu/cgi-bin/get-visit-sta...rkupFormat=html http://archive.stsci.edu/proposal_search.p...st&id=11990 -------------------- |
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Apr 12 2009, 06:48 PM
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#30
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
FYI, Hubble is presently studying Hartley-2 to try to pin down the basic properties of the nucleus, Observations have also been carried out by Spitzer, but I have noy seen results published yet http://adsabs.harvard.edu/abs/2008sptz.prop50593L |
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May 21 2009, 07:15 AM
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#31
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
A nice presentation "Remote Detection of Life on Earth ….inferences from EPOXI"
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May 26 2009, 05:05 AM
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#32
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
Hi all, I just noticed a new article on the EPOXI website by the EPOCh P.I. Drake Deming: http://epoxi.umd.edu/2science/alienmaps.shtml Enjoy! ~Rich The article Alien Maps of an Ocean-Bearing World is now on arxiv |
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Jun 7 2009, 06:40 AM
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#33
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
There is a mission update on the EPOXI site: http://epoxi.umd.edu/1mission/status.shtml
Characterizing Comet Hartley 2 Although the EPOXI mission's spacecraft is in a period of relative inactivity, the team is still actively working on a variety of questions. One of the key areas of investigation is the characterization of the next target, comet Hartley 2. Several investigations have been carried out to characterize the nuclear size and albedo, the large dust, and the rotation of the nucleus. These investigations have been aimed for the period before the nucleus begins outgassing significantly as it approaches the sun. Observation were taken with the Spitzer Space Telescope in August 2008. The analysis of those data yields a nuclear effective radius of 0.6 km, slightly smaller than, but still comparable to, the size deduced using the European Infrared Space Observatory at the previous apparition. These observations also show that there is a trail of large dust particles released much earlier and still orbiting the sun close to the nucleus. This is a common phenomenon among comets. The next step was an effort to determine the rotational period in order to design the observing sequence for the approach to the comet. A series of observations with the Hubble Space Telescope in late April were somewhat puzzling. Subsequent observations with a variety of ground-based telescopes, particularly with Gemini-South and Gemini-North on the same night, have suggested a rotational period near 2/3 day, but with narrow minima that were not caught in the HST observations. |
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Jun 21 2009, 06:38 PM
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#34
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
From the latest Discovery and New Frontiers Newsletter
Although the EPOXI mission's spacecraft is in a period of relative inactivity, the team is actively working on a number of areas of interest, including characterizing the next target, comet Hartley 2. Several investigations have been carried out to characterize the nuclear size and albedo, the large dust, and the rotation of the nucleus. These studies are timed for the period before the nucleus begins outgassing significantly as it approaches the sun. Another effort is to determine the Hartley 2’s rotational period to design the observing sequence for the approach to the comet. A series of observations with the Hubble Space Telescope in late April were somewhat puzzling. Subsequent observations with a variety of groundbased telescopes, particularly with Hawaii’s GeminiSouth and GeminiNorth on the same night, suggest a rotational period near 2/3 day, but with narrow minima that were not caught in the HST observations. The team is preparing to continue its role in testing software that could lead to improved interplanetary network communications. Last fall, a NASAwide team used DisruptionTolerant Networking, or DTN, software to transmit dozens of space images to and from the Deep Impact spacecraft which was more than 20 million miles from Earth. The test was called DINET (Deep Impact DTN experiment). Computers on the ground at JPL were used to simulate stations on Earth, Mars, and the Martian moon Phobos. The experiment was successful, with all the data transmitted without corruption even as various faults and breakdowns in the system were simulated. The team was pleased to support this activity that will ultimately lead to much better communications across the solar system. The Preliminary Design Review for DINET2 was conducted on May 13. The current timeline is being reviewed to determine when to begin DINET2 activities on the spacecraft. It may begin following the infrared imaging of Earth at high southern latitudes scheduled for August 17. |
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Jun 26 2009, 05:07 AM
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#35
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
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Jun 30 2009, 06:24 PM
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#36
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
There was a somewhat distant Earth flyby of Epoxi on 29 June at some 1.3 million km ... distant yet Epoxi is still closer to Earth than Planck is at the moment. Next close-ish approach at the end of the year
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Aug 1 2009, 03:39 PM
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#37
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
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Aug 28 2009, 06:39 PM
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#38
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
Browsing the DSN schedule (http://rapweb.jpl.nasa.gov/Planning/TMODMISS.pdf) I noticed that EPOXI is to conclude in November 2010 after the Hartley flyby, but the document gives a "probable end" date for the mission of 31 October 2011. Any idea what they plan to use the spacecraft for during the intervening year?
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Aug 29 2009, 05:03 PM
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#39
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Junior Member Group: Members Posts: 57 Joined: 21-September 06 Member No.: 1172 |
Any idea what they plan to use the spacecraft for during the intervening year? EPOXI trajectory from HORIZONS lasts till February 1, 2012. My program predicts several distant flybys of tiny asteroids and pass through cloud of Schwassmann-Wachmann comets: CODE Object Name Distance(AU) Date 73P-BB/Schwassmann-Wachmann 0.15935 2011-May-30 73P-V/Schwassmann-Wachmann3 0.06787 2011-Jun-15 73P-BD/Schwassmann-Wachmann 0.06865 2011-Jun-21 73P-BG/Schwassmann-Wachmann 0.06644 2011-Jun-28 73P-BR/Schwassmann-Wachmann 0.07153 2011-Jul-02 73P-BF/Schwassmann-Wachmann 0.09753 2011-Jul-23 73P-AT/Schwassmann-Wachmann 0.11083 2011-Aug-27 I guess they could tweak spacecraft's trajectory and study some of these objects. |
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Aug 31 2009, 05:47 AM
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#40
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
I wrote to EPOXI PI to ask for some clarifications and he tells me that
QUOTE Oct 2011 is the official end of our contract from NASA for EPOXI, but that includes the preliminary analysis phase. Our current plan is that spacecraft operations will end in Dec 2010.
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Sep 17 2009, 05:09 AM
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#41
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
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Sep 24 2009, 12:49 AM
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#42
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Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
I'm pretty sure the answer is "no" but I thought I'd check here...has there been a PDS release of any of the Deep Impact / EPOXI data from after the Tempel 1 encounter? Specifically, have any of the MRI or HRI images of Earth and/or Moon hit the PDS?
--Emily -------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
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Sep 24 2009, 06:02 AM
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#43
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
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Sep 25 2009, 08:50 AM
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#44
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
Hi all:
Just a quick update. EPOXI scientists have discovered water absorption features on the moon. The data was obtained from the IR spectrometer calibrations taken in December and twice in June. Chandryaan's M3 instrument also observed similar absorption features. This was published in Science yesterday. Read more here: http://epoxi.umd.edu/2science/hydratedmoon.shtml ~Rich |
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Dec 14 2009, 06:31 PM
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#45
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
Yet another EPOXI-related paper on arXiv:
Studying the atmosphere of the exoplanet HAT-P-7b via secondary eclipse measurements with EPOXI, Spitzer and Kepler |
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Dec 22 2009, 08:21 PM
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#46
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
*cough* Gamma-corrected, 650 nm "orange" (actually red), 550 nm green and 450 nm blue filter HRIV composite with channel mix to bring the channels to sRGB spec. Err... anyone know of any good image deconvolution software? -------------------- |
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Dec 22 2009, 09:52 PM
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#47
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Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
Egads. Merry Christmas from EPOCh! Thanks for the heads up, Gordan. I think I'll sit this one out and watch you wizards try to make something better of these data
Now if I could only remember why I was asking that question in the first place... --Emily -------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
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Dec 22 2009, 11:48 PM
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#48
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
23 frames from March 18, 2008, covering over 5.5 hours, again motion-interpolated in an AVI file (1 meg). I believe there's material for a complete rotation as it goes on to March 19 so this is still a work in progress.
-------------------- |
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Jan 18 2010, 07:34 PM
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#49
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
No one seems to have noticed this release yet
Sun Glints Seen from Space Signal Oceans and Lakes |
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Jan 18 2010, 07:39 PM
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#50
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
Ooh, neat! More, higher resolution movies of Earth! Can't wait for it to hit PDS in about a couple of years from now!
-------------------- |
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Jan 18 2010, 07:44 PM
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#51
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Senior Member Group: Members Posts: 1645 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
No one seems to have noticed this release yet Sun Glints Seen from Space Signal Oceans and Lakes Interesting that they are implying it may be possible to see sun glints on extrasolar planets. -------------------- Steve [ my home page and planetary maps page ]
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Feb 28 2010, 09:06 AM
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#52
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
PDS RELEASES EPOXI (EPOCh) MISSION DATA
The NASA Planetary Data System is pleased to announce release of the data from EPOXI, Extrasolar Planet Observation and Characterization (EPOCh) stage of the mission. The delivery includes raw and calibrated images (exoplanet transits and Earth) and infrared spectra (Earth) acquired during 2008. The data are available through the PDS Small Bodies Node. To see and download the data as well as mission and instruments information, go to: http://pdssbn.astro.umd.edu/missions/epoxi/ |
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Mar 5 2010, 05:32 AM
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#53
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
After more than six months, the EPOXI mission site has some new updates. Nothing particularly interesting anyway
QUOTE As the EPOCh team moves from processing data to writing papers about their results, the DIXI team is ramping up its activities in preparation for the encounter with comet Hartley 2 on November 4.
The majority of the data from EPOCh have been made public both at the Small Bodies Node of NASA’s Planetary Data System (PDS-SBN) and at the Multi-Mission Archive at Space Telescope (MAST). A few datasets taken in 2009 and some derived data (such as the final light curves of transiting planets) still remain to be delivered. There were two significant activities for DIXI in February. On February 16 we carried out the first of several cruise calibrations that are planned. The others will be in the summer, a few weeks prior to encounter, and a few weeks after encounter. These data ensure that we understand the operation of the instruments and can readily provide calibrated data after the encounter. The second significant activity in February was a face-to-face meeting of the science team with key members of the operations team to lay out the detailed sequence of observations to be made during the encounter (much like the Sequence Symphony from Deep Impact). These observations will include observations on approach starting 60 days prior to closest approach and observations on departure for 21 days. The details of these plans must be decided well in advance because it is necessary to test them extensively on simulators in order to be sure that everything operates as planned. Deep space flyby encounters such as this one do not allow any opportunity to redo any observations if something goes wrong and last minute changes are very risky. Thus these encounters are dealt with much more rigorously than are observations, e.g., with telescopes in orbit around Earth. For those observatories, it is essential to ensure the safety of the spacecraft and instruments but if the observation fails it can be repeated. We have no chance to repeat the observations. We will continue to change some details to the observing sequence over the next few months but the basic approach is completely determined at this time. |
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Mar 13 2010, 11:40 AM
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#54
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
According to the two Facebook profiles related to the mission (EPOXI Mission and Deep Impact Flyby), AutoNav on the flyby probe, unused for years, is being checked next Tuesday.
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May 11 2010, 05:09 AM
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#55
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
today on arXiv: The nucleus of 103P/Hartley 2, target of the EPOXI mission
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Jun 24 2010, 07:33 AM
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#56
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
EPOXI is now 3.5 days from its final(?) Earth flyby. It's already closer to Earth than Herschel and Planck!
-------------------- |
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Jul 1 2010, 06:58 PM
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#57
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Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
Update on the Earth flyby with a few notes about the November encounter with Hartley 2 posted on the Deep Impact website:
http://epoxi.umd.edu/1mission/status.shtml -------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
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Aug 29 2010, 09:19 AM
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#58
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
There was an interesting paper on Hartley 2 this week on ArXiv.
In particular, it is predicted that H2's surface will not be too different from comets already visited by spacecraft. It seems to be loosing a significant percentage of its radius at each perihelion, and could be extinct in just a century. The author also calls for a mission to a really old comet like Wilson-Harrington or a relatively old one like Encke. He predicts that they "will have a more extreme surface morphology, than the cometary surfaces that have been imaged up to now" |
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Sep 4 2010, 01:33 AM
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#59
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Newbie Group: Members Posts: 14 Joined: 18-March 09 From: Pasadena, CA USA Member No.: 4677 |
Salutations UMSF members,
We just completed a point-spread function calibration of the HRI this morning in preparation for Encounter. We also uplinked and activated the sequences to take the first 20-days of approach images from E-60days to E-40days. The first images should clock out around 13:30 UTC Sunday 9/5 with the images hitting the ground at 14:23 UTC. There's talk of putting a few of these on the website, but 60-days out, it should be just a fuzzy blob a few pixels across. Keep refreshing epoxi.umd.edu or the EPOXI facebook page for updates! ~Rich |
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Sep 4 2010, 06:03 AM
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#60
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
Thanks for the update, Rich, really looking forward to this encounter.
-------------------- |
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Sep 8 2010, 05:37 PM
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#61
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
first Hartley 2 pictures from Deep Impact
http://epoxi.umd.edu/3gallery/Hartley2_first_light.shtml |
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Sep 14 2010, 06:33 AM
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#62
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
Any Epoxians here? Would love to know which current SPICE kernel to use in my realtime simulation (www.dmuller.net/epoxi ... version 3 rolling out in due course):
spk_drm230_WithBurn-full.bsp or spk_od230_NoBurn-full.bsp Thanks in advance! -------------------- |
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Oct 5 2010, 09:39 PM
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#63
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Senior Member Group: Members Posts: 1585 Joined: 14-October 05 From: Vermont Member No.: 530 |
I've attempted to create an RSS feed for the "Daily Comet" at http://epoxi.umd.edu/6outreach/daily.shtml here:
http://feedity.com/rss.aspx/umd-edu/UVdbWlZV (I'm sure someone is about to post an official one, but I couldn't find it, so I got to try out feedity.com's advanced features.) Also, I'd suggest the moderators split this thread into a Comet Hartley Encounter thread beginning with the Sept. 3rd post. |
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Oct 11 2010, 05:27 PM
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#64
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
after Deep Impact, after EPOXI, an encore...
QUOTE [NASA] REQUEST FOR INFORMATION (RFI) In February 2011, the Deep Impact spacecraft will complete its mission (renamed EPOXI) for a study of extrasolar planets during its cruise to encounter Comet Hartley 2. This Request for Information (RFI) solicits input from the broad space science community that would contribute to NASA's study of possible new uses for the NASA Deep Impact/EPOXI spacecraft beyond its current mission and would support NASA's science objectives in any of SMD's research disciplines (Astrophysics, Earth Science, Heliophysics, and Planetary Science). Responses to this RFI will be used to inform NASA's program planning. The RFI is posted on the NASA research opportunity homepage at: http://nspires.nasaprs.com/ (select "Solicitations" then "Open Solicitations" then "NNH11ZDA003L"). The response date is November 5, 2010. For further information on this RFI, please contact: Mr. William Knopf Science Mission Directorate NASA Headquarters wknopf@hq.nasa.gov |
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Oct 11 2010, 06:14 PM
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#65
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
I'd been wondering if they would try an XXM with it
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Oct 11 2010, 06:55 PM
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#66
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
Of course with the 4.15 kg of fuel remaining I doubt that they will manage to do anything more significant than EPOCh-like observations.
I tried to play a little bit with the orbital elements given in the RFI document, but it seems like the probe will not come back to the vicinity of Earth before 2018, so no gravity assist possible |
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Oct 12 2010, 07:39 PM
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#67
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Senior Member Group: Members Posts: 1465 Joined: 9-February 04 From: Columbus OH USA Member No.: 13 |
Any Epoxians here? Would love to know which current SPICE kernel to use in my realtime simulation (www.dmuller.net/epoxi ... version 3 rolling out in due course): spk_drm230_WithBurn-full.bsp or spk_od230_NoBurn-full.bsp Thanks in advance! I'd be curious to know too. I just published a Hartley 2 app that runs on Android devices & used the spk_od230_NoBurn-full.bsp file. It seems that that's still the file with the most recent datestamp on the NAIF website. Searching on "hartley" in the Android market will bring up the app. Joe -------------------- |
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Oct 12 2010, 08:07 PM
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#68
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
I get the loading screen, then it crashes out
CODE The application Hartley2 (process com.naif.spicedemo3) has stopped unexpectedly DroidX on 2.2 |
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Oct 12 2010, 10:29 PM
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#69
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Senior Member Group: Members Posts: 1465 Joined: 9-February 04 From: Columbus OH USA Member No.: 13 |
I get the loading screen, then it crashes out CODE The application Hartley2 (process com.naif.spicedemo3) has stopped unexpectedly DroidX on 2.2 Thanks for checking it out--I just tried it on the 2.2 emulator & indeed it crashed. I just uploaded a new version to the market & would appreciate it if you give it another try. -------------------- |
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Oct 12 2010, 10:44 PM
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#70
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
Yup - it works now
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Oct 12 2010, 11:58 PM
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#71
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Senior Member Group: Members Posts: 1465 Joined: 9-February 04 From: Columbus OH USA Member No.: 13 |
Yup - it works now Thanks for helping me test this--I only have a version 1.6 device (G1) & for later versions the emulator can only go so far, like it doesn't test the GPS features. I trust that your latitude and longitude were displayed correctly? If it can't read the geolocation, it defaults to Greenwich (0W, 51.67N). -------------------- |
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Oct 21 2010, 11:23 AM
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#72
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Senior Member Group: Members Posts: 1465 Joined: 9-February 04 From: Columbus OH USA Member No.: 13 |
Managed to get a shot of Hartley 2 the other night:
http://i187.photobucket.com/albums/x269/jm..._garden_det.jpg Here's a little wider context: http://i187.photobucket.com/albums/x269/jm...103p_garden.jpg That's a 60-second exposure with an Olympus E-510 DSLR, 1000mm refracting telescope as a telephoto lens. Stellarium had this configuration: http://i187.photobucket.com/albums/x269/jm...tellarium-1.png By the time of the Deep Impact flyby on Nov. 4th around 10:02 a.m. ET, Hartley 2 will be a little further away (0.156 AU vs. 0.122 AU). It should be possible to photograph the comet that morning. From my location in Ohio Hartley 2 will rise around midnight on Nov. 4 and will be at about 60 degree elevation in the south around daybreak, and it will be a new moon. Ah, to be in Hawaii to photograph it at the actual time of the flyby--among other advantages. ADMIN : Embedded images changed to links. Don't put huge images in-line in posts. -------------------- |
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Oct 21 2010, 02:08 PM
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#73
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Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
At what point will Deep Impact's pictures be higher resolution than Earthbound observatories'? I thought I'd seen that information on Emily's blog, but I can't find it now...
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Oct 21 2010, 02:28 PM
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#74
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
Well, neither can really resolve the nucleus. DI will likely be able to do so just several hours before C/A. Calculating when the pixel scale on the coma will exceed earthbound observations is probably not a very useful number.
-------------------- |
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Oct 21 2010, 02:48 PM
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#75
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Senior Member Group: Members Posts: 1074 Joined: 21-September 07 From: Québec, Canada Member No.: 3908 |
About the flyby, here is an excerpt from the official encounter schedule (http://epoxi.umd.edu/7press/schedule.shtml):
"The cometary nucleus will be resolved ~1 hour out with the spacecraft 45,000 km away from its target. **Closest approach of comet Hartley 2 is expected to occur at ~6:50 am PDT at a distance of 700 km.** [...] The MRI pixel scale at closest approach will be 7 m/pixel, giving a nuclear diameter of ~170 pixels in the highest resolution images." |
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Oct 21 2010, 04:23 PM
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#76
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Senior Member Group: Members Posts: 1465 Joined: 9-February 04 From: Columbus OH USA Member No.: 13 |
About the flyby, here is an excerpt from the official encounter schedule (http://epoxi.umd.edu/7press/schedule.shtml): "The cometary nucleus will be resolved ~1 hour out with the spacecraft 45,000 km away from its target. **Closest approach of comet Hartley 2 is expected to occur at ~6:50 am PDT at a distance of 700 km.** [...] The MRI pixel scale at closest approach will be 7 m/pixel, giving a nuclear diameter of ~170 pixels in the highest resolution images." Maybe this calculation works: Counting Hubble as an earth-bound telescope, and taking its resolution to be 0.05 arc-seconds, at closest approach (about 0.12 AU, 18e6 km) and with a nucleus diameter of 1.2 km, the resolution would be at best around 16 pixels. So DI would have to be about 10x further away, or 7000 km to be roughly equal. That's about 10 minutes before closest approach. The Hartley 2 picture actually released on the Hubble site was taken much earlier, on Sept. 25, when the comet was .213 AU away and the resolution around 9 pixels. -------------------- |
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Oct 21 2010, 11:07 PM
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#77
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Interplanetary Dumpster Diver Group: Admin Posts: 4404 Joined: 17-February 04 From: Powell, TN Member No.: 33 |
and the resolution around 9 pixels. Do you mean 9km/pixel? Or the nucleus spanned 9 pixels? Or the coma spanned 9 pixels? -------------------- |
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Oct 27 2010, 05:40 PM
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#78
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
Nature published today a nice summary of the flyby http://www.nature.com/news/2010/101026/full/4671013a.html
Am I the only one intrigued by this story of cyanogen? |
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Oct 27 2010, 05:44 PM
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#79
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Senior Member Group: Members Posts: 1585 Joined: 14-October 05 From: Vermont Member No.: 530 |
Am I the only one intrigued by this story of cyanogen? They published a graph here: http://epoxi.umd.edu/3gallery/20101021_CN.shtml I might as well also link to Emily's post from the presser, since I'm already posting. http://planetary.org/blog/article/00002735/ |
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Oct 29 2010, 05:16 PM
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#80
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Member Group: Members Posts: 568 Joined: 20-April 05 From: Silesia Member No.: 299 |
First look at the shape of a comet Hartley 2 !!! For now from Earth.
Link to Emily's post: http://www.planetary.org/blog/article/00002742/ NASA's link: http://www.nasa.gov/mission_pages/epoxi/epoxi20101028.html -------------------- Free software for planetary science (including Cassini Image Viewer).
http://members.tripod.com/petermasek/marinerall.html |
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Oct 29 2010, 05:44 PM
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#81
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Member Group: Members Posts: 568 Joined: 20-April 05 From: Silesia Member No.: 299 |
Additional observations of comet Hartley 2 from 29 October (fourth row).
http://www.naic.edu/~pradar/103P -------------------- Free software for planetary science (including Cassini Image Viewer).
http://members.tripod.com/petermasek/marinerall.html |
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Oct 29 2010, 08:28 PM
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#82
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Senior Member Group: Members Posts: 3516 Joined: 4-November 05 From: North Wales Member No.: 542 |
Emily's post on the elongated shape of this and other comets http://www.planetary.org/blog/article/00002742/ started me off wondering if elongated shapes are a particular feature of comet nuclei and why that might be so. Here's what I came up with.
Think of a framed picture with an even width of mount all round. The frame is, proportionately, less elongated than the picture. Reverse the process and it's easy to see that removing uniform layers of material from any slightly irregular object will leave a progressively more flattened and elongated residue. Individual cases can have individual explanations of course but I wonder if, statistically, the shapes of comet nuclei could provide a measure of the amount of material lost and therefore the likely original size of these bodies before they were perturbed into low perihelion orbits? |
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Oct 29 2010, 09:07 PM
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#83
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Yeah, I was just thinking about that too, coincidentally. Haven't had time to really muse on it, but my first thought was whether comet nuclei like Borrelly & now Hartley-2 are products of mergers of binary objects. Are the rotation axes on both such that they 'tumble end-over-end'? That might be an interesting correlation, if it exists.
-------------------- 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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Oct 29 2010, 09:27 PM
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#84
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Senior Member Group: Members Posts: 3516 Joined: 4-November 05 From: North Wales Member No.: 542 |
What is the most likely origin of a contact binary? It could be erosion of an elongated object until the neck breaks.
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Oct 29 2010, 10:52 PM
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#85
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Member Group: Members Posts: 128 Joined: 10-December 06 From: Atlanta Member No.: 1472 |
Reverse the process and it's easy to see that removing uniform layers of material from any slightly irregular object will leave a progressively more flattened and elongated residue. I think even if you start with a perfect spherical body, the effect of spin axis on insolation results in asymmetrical shapes. If the spin axis is perpendicular to the orbital plane, equitorial regions receive more light and the resulting shape is elongated (ellipsoid). On the other hand, if the spin axis is significantly different from perpendicular, then the summer pole at perihelion receives more light and the end result is a squashed sphere (asymmetrical spheroid). |
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Nov 1 2010, 05:59 PM
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#86
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Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
Are most comets we've visited primordial, or shattered debris from objects deeper in the Kuiper Belt? I think the comets we usually see are broken off chunks of KBO's, with only the very occasional "raw" object. My thought is that debris from a collision is much more likely to be elongated than round due to the types of forces ejecting material away from an object; ie circular and radial forces from the point of impact.
-------------------- 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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Nov 2 2010, 02:57 PM
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#87
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Senior Member Group: Members Posts: 1443 Joined: 26-July 08 Member No.: 4270 |
Time lapse observations of Hartley 2 from EPOXI showing rotation of the comet as seen in the drection of plume(s).
http://www.youtube.com/watch?v=wMRMHnxBQ8A -------------------- -- Hungry4info (Sirius_Alpha)
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Nov 2 2010, 03:41 PM
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#88
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Member Group: Members Posts: 252 Joined: 5-May 05 From: Mississippi (USA) Member No.: 379 |
NASA TV Coverage of the EPOXI Encounter
The shuttle has it's own TV schedule, but these are also listed on THAT TV schedule! However, if something changes with the shuttle anything might happen. REMEMBER the Encounter is on the (Media Channel) & the Post Encounter is on the (Public Channel) NASA TV Schedule November 4, Thursday 9:30 - 11:30 a.m EST (13:30 GMT) - Live Commentary and Coverage of the EPOXI Spacecraft Close-Up Encounter of Comet Hartley 2 – JPL(Media Channel) 4 p.m. EST (20:00 GMT) - EPOXI Encounter of Comet Hartley 2 Post Encounter News Briefing – JPL (Public Channel) Jack |
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Nov 3 2010, 11:09 PM
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#89
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Senior Member Group: Admin Posts: 3108 Joined: 21-December 05 From: Canberra, Australia Member No.: 615 |
Watch the EPOXI encounter from the spacecraft's perspective through this fantastic, brilliant, wonderful and downright best program EVER - Eyes on the Solar System.
Well somebody had to tell you all it was there |
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Nov 4 2010, 12:14 AM
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#90
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
Be kind, it's still in Beta
But go find the NEAR mission and watch it's orbital phase with Eros.... see the Pioneer 11 flyby of Jupiter, and go 'OMFG' at the Ulysses trajectory There's a million things we're still trying to put into it - chances are any suggestions someone might have, we've already got it on a very very unfunded list of 'love to put in...' - but make suggestions |
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Nov 4 2010, 12:24 AM
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#91
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Senior Member Group: Admin Posts: 4763 Joined: 15-March 05 From: Glendale, AZ Member No.: 197 |
- but make suggestions I'd like to see the solar system at the start of stellar fusion. -------------------- If Occam had heard my theory, things would be very different now.
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Nov 4 2010, 02:22 AM
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#92
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Senior Member Group: Admin Posts: 3108 Joined: 21-December 05 From: Canberra, Australia Member No.: 615 |
djellison said: Be kind, it's still in Beta
That it may be, but it's still light years ahead of anything else! Good idea about suggestions, but maybe just not here....maybe here instead. |
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Guest_cassioli_* |
Nov 4 2010, 10:14 AM
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#93
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Guests |
Does anybody know of any webpage showing live minute-by-minute mission status, as sometimes happens for NASA missions?
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Nov 4 2010, 11:07 AM
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#94
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Senior Member Group: Members Posts: 1443 Joined: 26-July 08 Member No.: 4270 |
The closest thing I know of is either the Eyes on the Solar System or the Real-Time Simulation provided by dmuller.
-------------------- -- Hungry4info (Sirius_Alpha)
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Nov 4 2010, 11:19 AM
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#95
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Senior Member Group: Members Posts: 2173 Joined: 28-December 04 From: Florida, USA Member No.: 132 |
Does anybody know of any webpage showing live minute-by-minute mission status, as sometimes happens for NASA missions? If it's eyewitness updates from the control center you're after, there's http://twitter.com/elakdawalla. "I'm planning on being at the Jet Propulsion Laboratory incredibly early in my morning tomorrow, showing up around 6:00 a.m. my time (13:00 UTC). I'll be Tweeting events as they happen, and blogging as quickly as I can after the fact." Also there is a deep impact Twitter page: Get short, timely messages from Deep Impact Flyby. |
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Guest_cassioli_* |
Nov 4 2010, 11:56 AM
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#96
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Guests |
damn, twitter does not work at office!
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Guest_cassioli_* |
Nov 4 2010, 12:02 PM
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#97
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Guests |
I'd like to see a real-time mission status update like this old one:
http://spaceflightnow.com/cassini/status.html |
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Nov 4 2010, 12:16 PM
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#98
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Forum Contributor Group: Members Posts: 1372 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
I installed the Eyes on the Solar System s/w at work .
Watches over shoulder for bosses........ |
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Nov 4 2010, 01:13 PM
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#99
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Member Group: Members Posts: 252 Joined: 5-May 05 From: Mississippi (USA) Member No.: 379 |
NASA TV should be covering it live.
9:30 (13:30 GMT) - 11:30 a.m. - Live Commentary and Coverage of the EPOXI Spacecraft Close-Up Encounter of Comet Hartley 2 – JPL (Public and Media Channels) 4 p.m. - EPOXI Encounter of Comet Hartley 2 Post Encounter News Briefing - JPL (Public Channel) http://www.nasa.gov/multimedia/nasatv/index.html http://www.neil-online.com/nasa/ Jack |
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Guest_cassioli_* |
Nov 4 2010, 01:40 PM
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#100
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Guests |
10 minutes to closest approach.
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