New Horizons late cruise, 500 Millions kms - ~200 million kms |
New Horizons late cruise, 500 Millions kms - ~200 million kms |
May 20 2014, 10:11 PM
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#1
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IMG to PNG GOD Group: Moderator Posts: 2251 Joined: 19-February 04 From: Near fire and ice Member No.: 38 |
New Horizon's distance from Pluto drops below 500 million km today. The main thread here has been active since before launch and until today.
Today is an appropriate day for a new thread and there are also less than 14 months until Pluto arrival (time flies!). The coming months will see more spacecraft activity than in recent years with optical navigation images of Pluto/Charon, images of Neptune etc. The next 14 months are going to be interesting to say the least. |
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May 20 2014, 10:30 PM
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#2
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Newbie Group: Members Posts: 15 Joined: 26-March 12 From: San Antonio, Texas Member No.: 6368 |
Interesting is an understatement. This is going to be a fun year. To think, in July 2015 we'll be the first humans to ever see Pluto.
-------------------- Axes Grind and Maces Clash!
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May 20 2014, 11:03 PM
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#3
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Yes, and to think, 2014 is the last year when no one knows what Pluto and it's satellites really look like.
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May 21 2014, 10:12 AM
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#4
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Forum Contributor Group: Members Posts: 1372 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
I was looking at Yaohua2000's website yesterday and noted the distance was nearly down to 500. Time flies when your having fun.
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May 21 2014, 01:54 PM
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#5
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Newbie Group: Members Posts: 15 Joined: 26-March 12 From: San Antonio, Texas Member No.: 6368 |
Mr. Stern, I would like to thank you so much for New Horizons. What you and your team have done and are doing, it's a privilege to see what amazing will come of this.
Thank you, James Sontag -------------------- Axes Grind and Maces Clash!
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May 21 2014, 06:43 PM
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#6
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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May 21 2014, 09:13 PM
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#7
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Mr. Stern, I would like to thank you so much for New Horizons. What you and your team have done and are doing, it's a privilege to see what amazing will come of this. Thank you, James Sontag Thank you James, it's an honor for all of us on New Horizons to make this science exploration dream come true. |
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Jul 15 2014, 12:24 PM
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#8
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Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
A question on behalf of Alan: New Horizons accomplished a trajectory correction maneuver yesterday. Someone on Twitter suggested this was the deepest-space-ever rocket burn. Is it? When/where was the last Voyager TCM?
-------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
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Jul 21 2014, 04:27 PM
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#9
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Nice piece on our optical navigation plans, written by Emily following last week's science team mtg: http://www.planetary.org/blogs/emily-lakda...v-campaign.html
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Jul 21 2014, 04:38 PM
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#10
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Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
Which reminds me, I got an answer to my question above from Twitter: The last TCMs of the Voyagers:
Voyager 1 = 1980-312/04:24 GMT after Saturn Flyby Voyager 2 = 1989-233/15:14 GMT after Neptune Flyby -------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
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Jul 21 2014, 04:47 PM
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#11
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Which reminds me, I got an answer to my question above from Twitter: The last TCMs of the Voyagers: Voyager 1 = 1980-312/04:24 GMT after Saturn Flyby Voyager 2 = 1989-233/15:14 GMT after Neptune Flyby Emily- These are great numbers to have, thanks. One note, DOY=233=21 Aug so I believe the last Vgr 2 burn was just *prior* to Neptune C/A. Didn't ck on the Saturn DOY... |
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Jul 21 2014, 07:37 PM
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#12
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Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
It's a very busy little system down to the limit of Hubble resolution, I'd be quite surprised if there aren't a number of other chunks of debris to add into the mix as these opnav campaigns proceed. Any redundancy in the obs campaign for as-yet unresolved moons/rings???
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Jul 25 2014, 03:10 AM
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#13
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Member Group: Members Posts: 540 Joined: 25-October 05 From: California Member No.: 535 |
https://twitter.com/NewHorizons2015/status/...4711553/photo/1
Getting ever so closer... Pluto-Charon from 400 million km away -------------------- 2011 JPL Tweetup photos: http://www.rich-parno.com/aa_jpltweetup.html
http://human-spaceflight.blogspot.com |
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Jul 25 2014, 03:24 AM
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#14
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Jul 25 2014, 08:35 AM
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#15
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Member Group: Members Posts: 293 Joined: 22-September 08 From: Spain Member No.: 4350 |
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Jul 25 2014, 11:55 AM
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#16
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Senior Member Group: Members Posts: 2346 Joined: 7-December 12 Member No.: 6780 |
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Aug 6 2014, 11:29 AM
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#17
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Junior Member Group: Members Posts: 24 Joined: 11-February 07 From: College Station, TX Member No.: 1709 |
Here is a press release about the radio telescope observations of Pluto & Charon using ALMA:
http://public.nrao.edu/news/pressreleases/alma-pluto Neat two-frame animation of the orbital motion |
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Aug 8 2014, 12:52 PM
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#18
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Junior Member Group: Members Posts: 20 Joined: 4-August 14 From: St. Louis, Missouri Member No.: 7230 |
Movie of Charon orbiting Pluto from LORRI images covering almost 1 full rotation.
http://www.planetary.org/multimedia/space-...on_2014-07.html http://pluto.jhuapl.edu/news_center/news/20140807.php Looks like a clock running backwards in time... appropriate for a spacecraft visiting never-before-seen ancient frozen worlds. |
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Aug 11 2014, 10:47 AM
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#19
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Junior Member Group: Members Posts: 77 Joined: 27-June 04 From: Queensland Australia Member No.: 90 |
By my calculation, an observer on New Horizons will "see" Pluto at an apparent magnitude of 9.01 at the moment. It will brighten to below Mag. 9 by the end of the week with 400 million kilometers to go. (Of course you can't see an object at mag. 9 with the naked eye. It has to be Mag. 6 or less in a dark sky)
I just thought you might like that bit of trivia. |
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Aug 15 2014, 03:23 PM
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#20
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Member Group: Members Posts: 149 Joined: 18-June 08 Member No.: 4216 |
Movie of Charon orbiting Pluto from LORRI images covering almost 1 full rotation. Looks like a clock running backwards in time... appropriate for a spacecraft visiting never-before-seen ancient frozen worlds. It's the 80s all over again. Just like watching Voyagers 1/2 approaching any one of Jupiter, Saturn, Uranus or Neptune and their moons (poetic licence sought here; the Jupiter flybys took place in 1979). Not long to wait until instant science time.. |
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Aug 15 2014, 05:25 PM
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#21
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Interplanetary Dumpster Diver Group: Admin Posts: 4404 Joined: 17-February 04 From: Powell, TN Member No.: 33 |
It's the 80s all over again. Just like watching Voyagers 1/2 approaching any one of Jupiter, Saturn, Uranus or Neptune and their moons (poetic licence sought here; the Jupiter flybys took place in 1979). Not long to wait until instant science time.. It really does feel like it! I remember this experience as Voyager and Triton grew larger and larger as Neptune approached (I imagine it was the same for the earlier encounters, but I wasn't old enough to follow). This seems, to tell the truth, a lot like approaching the set of moons from one of the gas giant but without the gas giant. Edit: This should have read "as Neptune and Triton grew larger and larger as Voyager approached." Doh... -------------------- |
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Aug 15 2014, 06:28 PM
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#22
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Member Group: Members Posts: 334 Joined: 11-December 12 From: The home of Corby Crater (Corby-England) Member No.: 6783 |
As I said in another thread, it is probably better to have this kind of encounter later in mankinds exploratory journey, so that we can not only take advantage of the better technology available on board, but also the amazing capabilities of the internet and social media, to engage those who are simply 'interested' as opposed to only those who are directly 'involved'.So that one may become the other.
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Sep 1 2014, 09:50 AM
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#23
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Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
Reading through the latest 'significant events' page on the Cassini website reveals that Cassini took three ISS optical navigation images of Pluto against background stars last Sunday (24th) to help with ephemeris data in pinning down Pluto's exact position for the New Horizons flyby.
IIRC this was undertaken earlier in the mission, but the data were lost due to a saving event. It's great to see the co-operation that exists between the teams on various missions. Hopefully it helped! |
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Sep 1 2014, 01:14 PM
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#24
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
IIRC this was undertaken earlier in the mission, but the data were lost due to a saving event. There are a couple of sets of Pluto images taken over the years, but I couldn't figure out if Pluto was actually detectable in them and which "dot" among a sea of stars and noise it was. -------------------- |
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Sep 1 2014, 03:08 PM
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#25
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Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
The images in question are N00228384, N00228385 and N00228386.
It looks as though Cassini was commanded to 'stare' at Pluto so that background stars move relative to it, rather than vice-versa, as several bright stars move 'S/SW' between the frames. However there's so many cosmic ray hits/hot pixels in there, I can't obviously see the target. (I assume Pluto's position is well-enough known that it occupies the exact centre of the image) No doubt the engineering team can clean up the images with dark frame subtraction, and pull Pluto out of the noise. I'm amazed that Cassini's cameras are of use in this regard, given the 4 billion km range to Pluto! |
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Sep 1 2014, 03:15 PM
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#26
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
The images in question are N00228384, N00228385 and N00228386. I can find 56 images with target description as "SKY, PLUTO" dating back all the way to 2007, all of them are red and green filter images. Edit: ahh, you're talking about raw images and the latest observation? -------------------- |
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Sep 1 2014, 04:47 PM
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#27
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IMG to PNG GOD Group: Moderator Posts: 2251 Joined: 19-February 04 From: Near fire and ice Member No.: 38 |
(I assume Pluto's position is well-enough known that it occupies the exact centre of the image) Yes, Pluto's position is well known but there are alsways some pointing errors even though Cassini's pointing is amazingly accurate and stable compared to e.g. Voyager and Galileo. But Pluto should still be close to the image center, very probably within 50 pixels from it. |
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Sep 1 2014, 05:28 PM
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#28
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Debuting today! Pluto Picture of the Day (PPOD): Daily pix from/about New Horizons, Pluto, and more! http://www.boulder.swri.edu/ppod/
Bookmark it if you like it. -Alan |
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Sep 1 2014, 07:08 PM
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#29
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Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
Yes, sorry Gordan, I've been looking at the latest three images from last week.
To my knowledge, the effort to aid the New Horizons mission has now involved Hubble, Cassini, Subaru, Magellan and the Canada/France Hawaii telescope. A very heartening collaborative effort to achieve the biggest 'bang for the buck' at Pluto and beyond. |
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Sep 1 2014, 07:13 PM
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#30
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Yes, sorry Gordan, I've been looking at the latest three images from last week. To my knowledge, the effort to aid the New Horizons mission has now involved Hubble, Cassini, Subaru, Magellan and the Canada/France Hawaii telescope. A very heartening collaborative effort to achieve the biggest 'bang for the buck' at Pluto and beyond. And Keck. But Cassini was used for another purpose: astrometry with parallax from 10 AU. |
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Sep 1 2014, 07:25 PM
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#31
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Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
Yes, Pluto's position is well known but there are alsways some pointing errors even though Cassini's pointing is amazingly accurate and stable compared to e.g. Voyager and Galileo. Cassini's trajectory is similarly amazingly accurate - apparently within 90 metres of planned position during the latest Titan flyby! |
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Sep 1 2014, 07:39 PM
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#32
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Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
Bookmarked - thanks!
Great to know we're invited along on the ride. Those images that finally start to exceed Hubble resolution will be phenomenal - I wonder what we'll see? |
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Sep 2 2014, 05:21 AM
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#33
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Member Group: Members Posts: 541 Joined: 17-November 05 From: Oklahoma Member No.: 557 |
When the resolution gets down to about 100 km per pixel, it might look something like the maps David Tholin, Marc Buie and Keith Horne came up with and published in this paper:
Mutual Occutation Results Thanks to the work Tholin and others put into making those observations and deciphering the results, we already have a better look at one hemisphere of Pluto (and Charon) than Hubble can give us. I'm looking forward to seeing how well they match up to direct pictures from New Horizons. I'm expecting they'll match pretty well. |
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Sep 2 2014, 10:24 PM
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#34
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Member Group: Members Posts: 706 Joined: 22-April 05 Member No.: 351 |
I read that Alan Stern showed an image at a recent event of New York City at the best resolution that New Horizons will achieve at Pluto. Does anyone have a link to this? My Google search failed. Thanks.
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Sep 2 2014, 10:28 PM
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#35
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
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Sep 2 2014, 10:38 PM
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#36
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Member Group: Members Posts: 279 Joined: 19-August 07 Member No.: 3299 |
An interesting and detailed report about the comments of Alan Stern about the final preparations of New Horizons.
A mission to Pluto enters the home stretch “Beginning in May, we exceed Hubble resolution,” Stern said, a reference to the best images of Pluto taken to date. “It will get better week by week” through the July flyby. |
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Sep 3 2014, 01:41 AM
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#37
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Junior Member Group: Members Posts: 45 Joined: 27-August 14 From: Private island on Titan Member No.: 7250 |
PBS better air a "Pluto All Night" special!
-------------------- aka the Vidiconvict
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Sep 3 2014, 03:50 AM
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#38
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Given the bit-rate from that distance, it might have to be a "Pluto All Month"...
Actually, though, that's something I'm curious about--plans for public broadcast of the encounter. Alan, have you guys developed anything detailed on this yet? -------------------- 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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Sep 3 2014, 04:01 AM
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#39
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Given the bit-rate from that distance, it might have to be a "Pluto All Month"... Actually, though, that's something I'm curious about--plans for public broadcast of the encounter. Alan, have you guys developed anything detailed on this yet? Nick- In fact, we just started that discussion today. -Alan |
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Sep 3 2014, 11:53 PM
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#40
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Outstanding!
Suggestion: You should invite noted space journalists & bloggers to participate; there are many such in the present amateur space enthusiast community! -------------------- 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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Sep 4 2014, 09:44 AM
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#41
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Senior Member Group: Admin Posts: 3108 Joined: 21-December 05 From: Canberra, Australia Member No.: 615 |
UMSF has been riding along with New Horizons since before she launched.
It's worth going back to page one of this thread and reading the first few posts. In fact read back through the 110+ pages as we followed the adventure. Thanks to Alan Stern for giving us his insights and feedback throughout the mission. I second Nick's suggestion. Maybe there's some good value of "space science's finest communicators" (many of them to be found here) getting a chance to share that unique moment in July next year. They can do some great outreach and best of all, they're free! |
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Sep 4 2014, 01:14 PM
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#42
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
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Sep 4 2014, 04:34 PM
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#43
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
I should know better than to try to teach the teacher. Great, looking very much forward to the plans; thanks, Alan!
-------------------- 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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Sep 5 2014, 06:51 PM
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#44
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
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Sep 8 2014, 02:52 PM
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#45
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Junior Member Group: Members Posts: 28 Joined: 17-April 08 From: Okemos, MI, USA Member No.: 4097 |
Debuting today! Pluto Picture of the Day (PPOD) Is there a PPoD archive? I got here a bit late and due to my busy job might not make it every day. (It seems like just yesterday when I had time to spend all day at my desk F5ing Where Is NH? until it crossed Lunar orbit.) |
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Sep 8 2014, 03:50 PM
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#46
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Is there a PPoD archive? I got here a bit late and due to my busy job might not make it every day. (It seems like just yesterday when I had time to spend all day at my desk F5ing Where Is NH? until it crossed Lunar orbit.) We're implementing an archive, also a subscribe (i.e., push) service. Should be just a couple of weeks now... |
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Sep 14 2014, 01:24 AM
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#47
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
We're implementing an archive, also a subscribe (i.e., push) service. Should be just a couple of weeks now... We got first light on Hydra in July, data only revealed it this month; story here: http://pluto.jhuapl.edu/news_center/news/20140912.php |
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Sep 14 2014, 09:29 AM
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#48
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Junior Member Group: Members Posts: 77 Joined: 27-June 04 From: Queensland Australia Member No.: 90 |
A question from a layman:
New Horizons is currently in Sagittarius as viewed from the Earth, and given its relative proximity to Pluto and the relatively low gravity of the Pluto system, it seems likely from the geometry that it will continue in that direction (roughly towards the centre of the galaxy). I realise that it may be diverted to a Kuiper body object, which may change that bearing) Given that we have a solar orbital velocity of 200km/s around the galaxy, if we superimpose New Horizon's solar-centric velocity of 14.6km/s (towards Sagittarius), does this mean that NH will very gradually spiral towards the galactic centre? - or is that a naive idea? |
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Sep 14 2014, 10:15 AM
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#49
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Senior Member Group: Members Posts: 2346 Joined: 7-December 12 Member No.: 6780 |
It will very roughly move along a Kepler ellipse around the galactic center.
But because the field of gravity of the Milky Way is poorly approximated by a mass point, instead better by a disk, the trajectory will additionally oscillate about the galactic plane. |
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Sep 14 2014, 10:47 AM
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#50
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Junior Member Group: Members Posts: 77 Joined: 27-June 04 From: Queensland Australia Member No.: 90 |
It will very roughly move along a Kepler ellipse around the galactic center. But because the field of gravity of the Milky Way is poorly approximated by a mass point, instead better by a disk, the trajectory will additionally oscillate about the galactic plane. Thank you. |
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Sep 18 2014, 04:21 PM
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#51
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Newbie Group: Members Posts: 1 Joined: 11-September 14 From: Lucas, TX Member No.: 7255 |
LOONNNGGG time watcher, first time poster.....
I was telling my 7 year old son about New Horizons (he was born on the one-year aniversary of the launch). He was particulary interested in the remoteness of Pluto and was astonished when I told him about how the sun is much less bright way out there on the edge of the solar system. Does anyone have a good practical way of simulating the lighting conditions out there? For example, is the amount of available light similar to the moonlight on a full moon night? Thanks |
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Sep 18 2014, 04:28 PM
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#52
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Member Group: Members Posts: 701 Joined: 3-December 04 From: Boulder, Colorado, USA Member No.: 117 |
Sure- sunlight is about 1000x fainter on Pluto than on Earth (~32x further from the sun, and the sun's brightness goes as 1/R^2). That sounds like a lot, but the human eye is amazingly adaptable- we can see fairly well in full moonlight, which is about a million times fainter than sunlight.
Illumination on Pluto is something like ordinary subdued indoor domestic lighting like you might have at home in the evening. If you have a camera which reports exposures settings you can check this- for a pair of similarly-exposed photos, illumination of the scene is proportional to (f-stop)^2/(exposure time). ["^2" means "squared"] [edit] As an example, if you expose an outdoor scene at 1/250th second at f11, and an indoor scene (with the same ISO) at 1/8th second at f2, the brightness ratio of the two scenes is about 950x. John |
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Sep 18 2014, 04:31 PM
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#53
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Senior Member Group: Members Posts: 2091 Joined: 13-February 10 From: Ontario Member No.: 5221 |
The Sun would be a point, not a disc, but still be over 200 times the brightness of the full moon (an average, given the elliptical orbit).
Phil Plait has a good article on this: http://blogs.discovermagazine.com/badastro...sun-from-pluto/ |
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Sep 18 2014, 04:35 PM
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#54
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
I believe it's about 250x brighter than a full moon. About 1/1500th as bright as the Sun at Earth.
Someone may want to check my maths on this....but.... One way to express it is with a camera. If you go outside with a DSLR and open the aperture fairly wide - you might get an exposure of, say, 1/4000th of a second ( the quickest exposure on many off the shelf consumer DSLR's ) Find a place where the same aperture results in an exposure of about 1/3rd of a second. That's how much darker it is on Pluto compared to the Earth. Alternatively - it's like going from an aperture of F2 to F38....but without the added benefit of great depth of field Doug |
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Sep 18 2014, 05:02 PM
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#55
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Senior Member Group: Members Posts: 2346 Joined: 7-December 12 Member No.: 6780 |
I guess, you intended to write "F1 to F38".
For the other values I got about the same. |
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Sep 18 2014, 05:16 PM
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#56
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
Yeah - I as thinking of my 50mm F1.4 - but rounded up
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Sep 18 2014, 08:18 PM
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#57
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Member Group: Members Posts: 121 Joined: 26-June 04 From: Austria Member No.: 89 |
A good way to simulate the brightness of the sun at pluto imho is when a solar eclipse at earth comes close to the totality phase.
I think about 15 to 10 minutes before totality arrives is just about the same brightness level at pluto..but this is only rough guess and depends on the eclipse geometry. Could one do the math for this please ? Shadows during this eclipse phase on earth are strange because of the thin sun sickle..shadows at pluto must be still more sharper with almost no penumbra visible. Robert |
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Sep 18 2014, 08:43 PM
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#58
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Senior Member Group: Members Posts: 3516 Joined: 4-November 05 From: North Wales Member No.: 542 |
shadows at pluto must be sharper with almost no penumbra visible. I have on just a couple of occasions managed to observe shadows cast by Venus. They are very faint because of course the surface brightness of Venus is thousands of times less than the Sun. But they are also very sharp, making the shadows of near and far tree branches impossible to distinguish. In terms of angular size our Venus is about the same as Pluto's Sun. |
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Sep 18 2014, 10:09 PM
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#59
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Senior Member Group: Members Posts: 2346 Joined: 7-December 12 Member No.: 6780 |
A good way to simulate the brightness of the sun at pluto imho is when a solar eclipse at earth comes close to the totality phase. I think about 15 to 10 minutes before totality arrives is just about the same brightness level at pluto..but this is only rough guess and depends on the eclipse geometry. Could one do the math for this please ? ... With a month of 29.5 days and an angular size of 32' for Sun and Moon, I get 3.2 seconds before/after totality to reduce brightness by a factor of 1500: 29.5d * 32' * 4 / 360° / 1500 / pi = 3.2 s. (The dependence of the area of the visible part of the Sun from time should converge towards linear near totality in this idealized case of zero totality time, 2nd order equivalent to a horizontally shrinking rectangle with constant height 32'. A circle (area r²pi) is a little smaller than a circumscribed square (area 4r²), therefore the factor 4/pi.) It's a little longer before/after totality for a larger angular size of the Moon, but further detail would be off topic in this thread. |
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Sep 19 2014, 12:17 AM
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#60
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Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
A fun experiment would to be get a room and cover the windows so that only 1/1000 of the area is window is uncovered. That would give an idea of how bright it would be inside a house anyways.
-------------------- 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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Sep 20 2014, 04:26 PM
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#61
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Senior Member Group: Members Posts: 1648 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
In terms of a total solar eclipse I agree with Gerald it would be just a few seconds before totality. The exact time depends on the eclipse and the relative sizes of the sun and moon. Even then, the scattered light from outside totality would alter things. I have programmed some empirical formulae to get the sun's brightness depending on the eclipse magnitude (fraction of solar diameter covered), and the relative sizes of sun and moon. I'll try and locate them.
There would also be a time during daily twilight (say on a clear day) when the overall illumination of the ground would be 1/1000th of daytime. I'm guessing it would be about 30 minutes after sunset, with a solar elevation of -6 degrees. The window experiment also sounds interesting. On a clear day the sky (without direct sunlight) has roughly 10% of the sun's light over the hemisphere. That would be over 20000 square degrees. Therefore if you have a window showing 200 square degrees of sky and no direct sun it might work. The diameter of the window would be about 15 degrees then, so one could stand about 4 times the width of the window away. -------------------- Steve [ my home page and planetary maps page ]
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Sep 20 2014, 04:53 PM
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#62
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Junior Member Group: Members Posts: 59 Joined: 25-December 05 From: Stevens Point, Wisconsin, USA Member No.: 619 |
...yet another way to look at it: about as bright a full moon expanded to around 8 degrees in diameter.
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Sep 22 2014, 09:25 PM
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#63
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IMG to PNG GOD Group: Moderator Posts: 2251 Joined: 19-February 04 From: Near fire and ice Member No.: 38 |
I moved a bunch of posts to this thread from the old main NH thread.
This thread will be the main thread for what remains of NH's cruise phase (an amazingly short time really, I feel as if NH was recently launched but there are now almost 9 years since it was launched). |
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Sep 23 2014, 04:10 PM
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#64
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Today's awesome PPOD pic is at http://www.boulder.swri.edu/ppod/
Soon you can sign up for push notifications.... And EVEN BETTER! Here's Amanda's latest Postcard from Pluto! http://plutopostcards.tumblr.com/post/9817...itous-things-to … Enjoy! |
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Sep 27 2014, 04:15 PM
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#65
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
PPOD/Pluto Picture of the Day now has an indexed archive! http://guinan.space.swri.edu/nhepo/archive_index
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Oct 2 2014, 06:49 PM
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#66
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
PPOD now allows you to sign up for push notifications. http://www.boulder.swri.edu/ppod/ |
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Oct 4 2014, 08:29 PM
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#67
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Junior Member Group: Members Posts: 48 Joined: 10-September 06 Member No.: 1129 |
Hey Alan, you've indicated before that the data from the Pluto flyby in July 2015 will trickle in slowly. Will we still get to see high res images come in as the approach happens or will we have to wait a bit?
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Oct 4 2014, 10:03 PM
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#68
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Senior Member Group: Members Posts: 2091 Joined: 13-February 10 From: Ontario Member No.: 5221 |
I read an interview (somewhere, don't have the link on me!) where the plan is basically that some images from around CA (those worthy of being under the newspaper headlines) are going to be given priority in the downlink sequence. So although it will take ages to get everything down, there won't be a second agonizing wait for the best stuff after July.
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Oct 4 2014, 10:11 PM
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#69
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Hey Alan, you've indicated before that the data from the Pluto flyby in July 2015 will trickle in slowly. Will we still get to see high res images come in as the approach happens or will we have to wait a bit? Every LORRI image that comes to the ground will be posted to see, with <24 hour delay. (LORRI is the hi-res imager). That will include the very best images we have at P-2 and P-1 days. After C/A, more and more will be downlinked as the bird spends increasing time downlinking v. gathering data. The full data downlink will take 16 months, but you will be along for the ride with us on approach, and on departure. |
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Oct 5 2014, 04:15 PM
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#70
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Senior Member Group: Members Posts: 1648 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
Interesting to see the PPOD 9/28 artist view, in light of the earlier discussion of the 1/1000 Earth illumination appearance.
http://guinan.space.swri.edu/nhepo/archive/2014/09/28 One might consider some of the assumptions of atmospheric parameters that would go into such a visualization. This includes optical depths of gas and aerosols, as well as their scale heights. The vantage point of the viewer above the mean terrain height helps the depiction of the surface haze layer. -------------------- Steve [ my home page and planetary maps page ]
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Oct 5 2014, 06:02 PM
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#71
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Junior Member Group: Members Posts: 48 Joined: 10-September 06 Member No.: 1129 |
Every LORRI image that comes to the ground will be posted to see, with <24 hour delay. (LORRI is the hi-res imager). That will include the very best images we have at P-2 and P-1 days. After C/A, more and more will be downlinked as the bird spends increasing time downlinking v. gathering data. The full data downlink will take 16 months, but you will be along for the ride with us on approach, and on departure. Awesome, thank you. I can't wait! |
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Oct 10 2014, 09:09 PM
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#72
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Junior Member Group: Members Posts: 88 Joined: 8-May 14 Member No.: 7185 |
Reddit AMA with the New Horizons team, - Q&A by Alan Stern et al. with space enthusiasts
http://www.reddit.com/r/IAmA/comments/2igk...s_new_horizons/ |
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Oct 12 2014, 11:43 PM
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#73
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
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Oct 13 2014, 05:31 AM
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#74
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Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
Looks great Alan! Getting so excited to see Pluto and Charon and the rest of the gang in the windshield.
-------------------- 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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Oct 13 2014, 02:54 PM
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#75
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Newbie Group: Members Posts: 15 Joined: 26-March 12 From: San Antonio, Texas Member No.: 6368 |
Very nice, Alan. Thank you for sharing.
What blows my mind, is that, I don't think most people realize that we will be the first humans to ever see Pluto. Man, just thinking about that is crazy. -------------------- Axes Grind and Maces Clash!
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Oct 13 2014, 11:32 PM
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#76
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Member Group: Members Posts: 166 Joined: 20-September 05 From: North Texas Member No.: 503 |
I don't think most people realize that we will be the first humans to ever see Pluto. Man, just thinking about that is crazy. You should have been around for the Voyagers spacecraft, and the first close-up views of so many planets and their moons. Completely new landscapes on a yearly basis that had never been seen before by any human in history. You are right. It is mind-blowing! |
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Oct 14 2014, 12:07 AM
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#77
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
considering i had just turned 10 by Aug ( v2) and sep (v1 ) of 1977
when the Voyagers launched ..... that era was a "time" the 1976 things and goings on Viking Voyager some of the Mariner missions All the astronomy books i could get my hands on were being OUTDATED by the time that a 8 to 12 year old could read them |
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Oct 14 2014, 12:22 AM
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#78
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Been seeing new worlds for the first time since Mariner 9.
Never, ever gets old. Not even a little bit. -------------------- 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 14 2014, 12:33 AM
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#79
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Senior Member Group: Members Posts: 2922 Joined: 14-February 06 From: Very close to the Pyrénées Mountains (France) Member No.: 682 |
Went to Pasadena from France on a B707 to be part of Planetfest 89 for VII Neptune encounter...was to be the last for a loooong time...and here we (nearly) are. Thank you Mr Stern and All...
-------------------- |
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Oct 14 2014, 03:41 AM
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#80
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
Went to Pasadena from France on a B707 to be part of Planetfest 89 for VII Neptune encounter...was to be the last for a loooong time...and here we (nearly) are. Thank you Mr Stern and All... Climber, all- We can;t wait to bring this too you, and to everyone, everywhere... fasten your seat belts! -Alan |
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Oct 14 2014, 03:45 AM
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#81
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Member Group: Members Posts: 813 Joined: 8-February 04 From: Arabia Terra Member No.: 12 |
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Oct 14 2014, 06:56 PM
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#82
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Member Group: Members Posts: 362 Joined: 13-April 06 From: Malta Member No.: 741 |
Is there going to be another planetfest like gathering for the Pluto flyby?
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Oct 15 2014, 11:58 AM
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#83
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Junior Member Group: Members Posts: 61 Joined: 20-March 10 From: Western Australia Member No.: 5275 |
I'm sure there will be.
Here in Australia, back in the day, Voyager was making its flyby through the Neptunian system. Our ABC (Australian Broadcasting Corp) had a 2 hour special. It was evening over here in Western Australia and we had a special public night (Monday) to view Neptune, btw, I'm a member of the Astronomical Society of the South West. So there we are, a tiny blue disc in our telescopes, and on the TV some mind blowing images of Neptune. I've only seen Pluto once via telescope, a 12.5" f6 Newt (superb optics btw). A dot amongst dots. So much looking forward to the flyby. Shame we don't have the delta V for orbit. |
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Oct 15 2014, 05:05 PM
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#84
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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 |
KBO targets for New Horizons (other than Pluto and Charon, of course) found!
http://hubblesite.org/newscenter/archive/r...s/2014/47/full/ |
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Oct 15 2014, 05:41 PM
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#85
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Member Group: Members Posts: 408 Joined: 3-August 05 Member No.: 453 |
Question - would the major targeting for such an object be done post Pluto system flyby, or (more propellant efficient, but perhaps more disruptive?) by tweaking the flyby parameters for a gravity assisted course correction?
Airbag |
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Oct 15 2014, 05:41 PM
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#86
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Administrator Group: Admin Posts: 5172 Joined: 4-August 05 From: Pasadena, CA, USA, Earth Member No.: 454 |
After the flyby. The science plan for the encounter is locked and loaded.
-------------------- My website - My Patreon - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
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Oct 15 2014, 05:52 PM
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#87
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
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Oct 15 2014, 06:01 PM
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#88
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Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
So, rough back-of-the-laptop calculation has a cruise time to KBO encounter of ~3.5 years. That's assuming constant speed, ~1 billion miles further to go. Here's to hoping a few more pop out of the woodwork!
-------------------- 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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Oct 15 2014, 06:16 PM
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#89
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Senior Member Group: Members Posts: 3516 Joined: 4-November 05 From: North Wales Member No.: 542 |
Wonderful news and big congratulations to the team.
Does 'definitely reachable' mean the target(s) can be approached arbitrarily closely? Can we look forward to seeing the selected one in as much detail as Pluto and Charon? EDIT: My question already answered by Emily http://www.planetary.org/blogs/emily-lakda...-has-a-kbo.html To summarise - Yes, close range is well within reach fuel-wise, but because the target's orbit will not be as accurately determined as Pluto's it will be harder to optimise the flyby distance perfectly for science. What would have been my next question is also answered. The definitely reachable target is a cold classical KBO. |
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Oct 15 2014, 08:32 PM
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#90
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Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
Terrific news! Congratulations to all the team for their indefatigable efforts in finding a candidate KBO.
I can't imagine that funding for a mission extension will be too hard to negotiate come the time A little early for image sequencing discussions perhaps, but assuming the object's orbit can be determined accurately enough, is NH capable of undertaking 'skeet-shoot' (as per Cassini at Enceladus) techniques for very close imaging, given the low-light levels and relative speed at closest approach? |
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Oct 16 2014, 05:31 AM
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#91
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Member Group: Members Posts: 541 Joined: 17-November 05 From: Oklahoma Member No.: 557 |
Well I have to say it ...
I always had faith in them. www.unmannedspaceflight.com/index.php?s=&showtopic=2048&view=findpost&p=37681 Congratulations! |
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Oct 16 2014, 09:57 AM
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#92
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Junior Member Group: Members Posts: 77 Joined: 27-June 04 From: Queensland Australia Member No.: 90 |
We'll soon see how similar Pluto is to Triton (or not as the case may be). Exciting times indeed.
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Oct 16 2014, 10:14 AM
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#93
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Member Group: Members Posts: 813 Joined: 8-February 04 From: Arabia Terra Member No.: 12 |
2016 -2017 (like 1990 -1991) should be a great time for bringing out books on the solar system. So, rough back-of-the-laptop calculation has a cruise time to KBO encounter of ~3.5 years. That's assuming constant speed, ~1 billion miles further to go. Here's to hoping a few more pop out of the woodwork! May have to delay that textbook by a couple of years! I asked Alex Parker about the possibility of searching for scattered disc objects: QUOTE We've tossed this idea around. It will require more study of the scattered disk population to know if this is feasible.
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Oct 16 2014, 07:33 PM
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#94
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Junior Member Group: Members Posts: 78 Joined: 16-October 12 From: Pennsylvania Member No.: 6711 |
They would most likely need to apply for Hubble time again. When someone inevitably writes a book on New Horizons they will have to mention the invaluable amount of help Hubble has done for the mission.
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Oct 16 2014, 09:07 PM
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#95
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Senior Member Group: Members Posts: 1585 Joined: 14-October 05 From: Vermont Member No.: 530 |
Mag 26.8 for PT1 ... according to Wikipedia, visible from 8m telescopes? They don't need hubble exclusively to track it?
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Oct 16 2014, 09:17 PM
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#96
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Junior Member Group: Members Posts: 78 Joined: 16-October 12 From: Pennsylvania Member No.: 6711 |
I meant if they wanted to look for a scattered disk object like SFJCody suggested. Not PT1.
Incidentally, which telescope do you think would be able to find KBOs better, Hubble or the Webb? |
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Oct 16 2014, 09:24 PM
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#97
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Member Group: Members Posts: 701 Joined: 3-December 04 From: Boulder, Colorado, USA Member No.: 117 |
We will probably try to track these guys from the ground. From our ground-based search campaign, we already have a huge amount of data covering the locations of these objects, from 6-meter and 8-meter telescopes, going back to 2011. These KBOs are too faint to have been *discovered* in those data, but now we know where look, we might be able to *recover* them from the images, and thus extend our knowledge of their orbits. We'll be working on that over the winter, and will also be considering future ground-based tracking observations. Future ground-based tracking won't be as precise as Hubble's, but may provide a useful supplement and backup to Hubble- we'll see.
John |
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Oct 16 2014, 09:35 PM
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#98
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
John, this is probably a very premature question, but if JWST launches as currently scheduled could it too play a part in final pre-encounter position & size observations of PT1? Main reason I ask is that STScI is to be the controlling organization for both scopes, if I'm not mistaken.
-------------------- 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 16 2014, 10:33 PM
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#99
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Member Group: Members Posts: 701 Joined: 3-December 04 From: Boulder, Colorado, USA Member No.: 117 |
Yes, quite possibly, *if* it launches in 2018- we certainly won't be counting on it! Keep in mind, of course, that PT1 isn't necessarily our final choice- the other two are still in the running.
John |
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Dec 7 2014, 02:06 AM
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#100
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
The NH final wakeup coverage is live now here. (began 0200 GMT/7 Dec)
EDIT: Also, here's a link to Eyes On The DSN. DSS43 at Canberra is currently listening for NH. -------------------- 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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