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It seems that much of the discussion below, debating the 'anticipated' dates, is moot, unless the historical record is in doubt. Several of the comments are themselves, undated.
It is not mentioned, so I would like to see the very distinctive features of the very low thrust orbital mechanics of this mission addressed/discussed/described. I suspect it is much like the trajectories of light sail spacecraft, in that the thrust is almost tangent to the current orbit, and chosen to drive the craft into 'higher' orbit, nearer the next target body, much more than to 'shoot it at' the target. I also suspect that it takes many (hundreds? of) orbits at 'full power' to lift it from a close (planetary) orbit, to get it to break back into a solar orbit (no longer bound to the previous body). Since it is now ('141229) only a few months from Ceres insertion, is it decelerating to allow capture (and avoid fly-by), or is the insertion a low-delta capture. It sounds like some of the other contributors might have, or have access to, the formulas and details of these trajectories and techniques. Wikidity (talk) 04:53, 31 December 2014 (UTC)
I'm not sure where to write this as I have just started adding articles to Wikipedia. I'm a JPL engineer that has delivered hardware and is now working ATLO on the DAWN spacecraft. I'd like to add comment to the page but would like to channel the info through the main person running the page. One change is... Technically, L3 Communications (?) Electron Technologies Inc. (L-3 ETI) (formerly a division of Boeing) of Torrance, CA, built the ion thrusters. JPL provides the integration and control of the Ion Propulsion System (IPS), which includes the Thruster Gimbal Assembly (TGA)(this is what I delivered), DCIU, PPU, XFS, and the Ion Thruster. Also, is there a page that shows the phase breakdown of NASA missions and can this article publish the cost profile (and any other info) per phase? I'd like to help, let me know. -gg3369 3 August 2006
I'm really curious to know how Ceres might look. I did not know this project (but so many years to reach it...) Please upload images to commons. It is better for all of us. -Pedro 20:00, 26 August 2005 (UTC)
AtIAFinFukuoka last week it was announced that Dawn will be postponed by six to nine months, probably launched early 2007, with no impact on the overall schedule thanks to ion propulsion.Hektor 11:03, 23 October 2005 (UTC)
I've dropped the one fair-use image, as part of our program of clearing out nonfree images. I notice the Dawn website has some photos of the real craft that would make nice substitutes (already on commons perhaps?) Stan 14:38, 9 December 2005 (UTC)
Source: NASA news release. It should be public domain as a U.S. gov't work, so I'll post it here, and we can work the information into the article. Jonathunder 22:59, 27 March 2006 (UTC)
NASA senior management announced a decision Monday to reinstate the Dawn mission, a robotic exploration of two major asteroids. Dawn had been canceled because of technical problems and cost overruns.
The mission, named because it was designed to study objects dating from the dawn of the solar system, would travel to Vesta and Ceres, two of the largest asteroids orbiting the sun between Mars and Jupiter. Dawn will use an electric ion propulsion system and orbit multiple objects.
The mission originally was approved in December 2001 and was set for launch in June 2006. Technical problems and other difficulties delayed the projected launch date to July 2007 and pushed the cost from its original estimate of $373 million to $446 million. The decision to cancel Dawn was made March 2, 2006, after about $257 million already had been spent. An additional expenditure of about $14 million would have been required to terminate the project.
The reinstatement resulted from a review process that is part of new management procedures established by NASA Administrator Michael Griffin. The process is intended to help ensure open debate and thorough evaluation of major decisions regarding space exploration and agency operations.
"We revisited a number of technical and financial challenges and the work being done to address them," said NASA Associate Administrator Rex Geveden, who chaired the review panel. "Our review determined the project team has made substantive progress on many of this mission's technical issues, and, in the end, we have confidence the mission will succeed."
So.. what do you wanna bet that if Ceres is actually re-declared a planet, Dawn won't have to worry about getting cancelled again? :P --Patteroast 15:45, 16 August 2006 (UTC)
Sorry, but this toggling of the launch date between 20 and 21 June that occurs every couple of weeks in the article is cracking me up. I just had to mention it ;-) Returning to lurk mode. Deuar 22:08, 10 September 2006 (UTC)
No, the person running NASA web site was not up to date with information from the JPL Payload team. Team members who have the schedules in front of them should know the launch of their instruments, don't you think? Amara 19:56, 18 May 2007 (UTC)
The slight damage to one of the solar arrays is not slight at all. The structure was damaged and deployment and other mechanical aspects can not be tested anymore. The electrical wireing of the solar panals was damaged. A delay is a decesarry, but not possible.--Stone 16:21, 19 June 2007 (UTC)
I really dislike the notion that Dawn is a "Satellite of: Vesta and Ceres". Strictly speaking that is outright false. After all the probe, as I write these words, is on Earth and is not a satellite. We don't know if it will ever be a satellite as it is possible that it could explode on launch, etc. And if one is going to call it a "satellite" then it is -- if all goes according to plan -- a future satellite of Sun afterwards a satellite of Vesta afterward a satellite of the Sun again and finally a satellite of Ceres. At no time will it be a satellite of both Vesta and Ceres. I really think that this needs to be reworded. Maybe a mission or planned mission to Vesta and Ceres. MichaelSH 00:09, 27 June 2007 (UTC)
Resolved
I would like to solicit broad input before proceeding with a rename of this article. The current Dawn Mission does not comply with Wikipedia standards for article naming, i.e. WP:CAPS. Becuase multiple renames leave an ugly trail of redirects, rather than simply lowercasing to Dawn mission it makes more sense to determine whether some other name, possibly including the use of parenthesis for disambiguation, makes more sense. How about Dawn (spacecraft)?Dawn (space mission)?Dawn (spaceflight)?Dawn (space exploration)? (sdsds - talk) 19:21, 31 August 2007 (UTC)
Hi all - not being familiar with this (and only finding it via the front page), the first paragraph currently says that the mission is to send a robotic space probe, but the following paragraph says that it's a human spacecraft. I'm presuming that no humans are onboard the probe? Could someone with more knowledge possibly clear this up? Or is it just me being stupid :) Richsage 20:44, 30 September 2007 (UTC)
The second paragraph states: "Dawn will be the first spacecraft to orbit two planetary bodies other than Earth and the Moon, and the first to visit Ceres and Vesta." This needs to be clarified at the least and probably edited. They Huygens-Cassini probe has been orbiting Saturn for several years now and other probes have also orbited planets. So something about this is either inaccurate or non-specific. Logan 5 19:31, 3 October 2007 (UTC)
In the lead sentence, would it be accurate to replace "most massive" with "largest" in describing Ceres and Vesta? I understand large implies volume rather than mass, but a) "largest" is simpler language and b) there isn't some larger but less massive object in the asteroid belt, is there? (sdsds - talk) 23:56, 12 October 2007 (UTC)
In the opening section, it is claimed that:
Neither body is planetary (or at least both are not - a case can be made for dwarf planet Ceres) so this isn't accurate.
If one claims it is the first to orbit two celestial bodies, then one has to add "(other than the Earth, Moon, and Sun)". This gets a bit awkward.
You can't say the first to visit more than one celestial body; the Voyager program has a whole laundry list of visited moons and planets.
As it doesn't seem to be very distinctive for orbiting, or visiting, celestial bodies - it really is only the first to reach one, stop, start up again, and go somewhere else, as opposed to he Voyager probes which only flew by non-stop. Maybe the mention that it is the first spacecraft to Vesta and Ceres can be incorporated into the first paragraph, and this second paragraph should be struck entirely. -- Vedexent (talk) - 13:49, 13 October 2007 (UTC)
I saw the first pictures of some stars and a nebula. Very impressing! I hope the second camera works also as good. --Stone (talk) 20:41, 8 January 2008 (UTC)
{{cite journal}}
: CS1 maint: multiple names: authors list (link)------Stone (talk) 07:36, 6 June 2008 (UTC){{cite journal}}
: CS1 maint: multiple names: authors list (link)-----------14:19, 11 June 2008 (UTC)During the swing at 27 minutes passed midnight on the 18th of February 2009 the closeesed approach is scheduled to be 565km. The Framing Cameras will take pictures of a several 100 km broad stripe of Mars running between Tharsis vulcano and Olympus Mons. The Cameras of the Mars express spacecraft will make pictures of the same region later to calibrate the cameras and to compare the two cameras. Dawn: Kursänderung am Nachbarplaneten Mars--Stone (talk) 12:22, 16 February 2009 (UTC)
I may have missed it, but where in the article does it talk about the kinds of cameras in the spacecraft? What kind of resolution is available? What kind of graphics format is being used? There was a link that indicated somebody was trying to build a camera for it, but there didn't seem to be any hard information as to what he had come up with? Were there any compromises as to what was desired, and what the actual result was? How many bits of color information are associated with the pixels, or bits of data? If an infrared camera is being included, how is the data being merged (if it is merged at all) with the regular data? Is raw data being transmitted back to earth, or is there some kind of redundancy and correction involved before it is transmitted? How many CCDs are being used? Does the camera have a shutter? If there is a shutter, how much power is required to open it? Is the spacecraft currently flying with the shutter closed, to protect the lens from micrometeors?216.99.198.176 (talk) 04:53, 17 August 2009 (UTC)
Removed the word 'so' before 'vital' in the sentence: 'Because the framing camera is so vital for both science and navigation, the payload has two identical and physically separate cameras (FC1 & FC2) for redundancy, each with its own optics, electronics, and structure.' Something is either vital or not. — Preceding unsigned comment added by 130.123.104.22 (talk) 23:09, 1 August 2011 (UTC)
I just marked the last sentence of the lead as needing a citation and as being dubious. for reference: Dawn is innovative in that it will be the first spacecraft to enter into orbit around a celestial body, study it, and then re-embark under powered flight to proceed to a second target. All previous multi-target study missions—such as the Voyager program—have involved rapid planetary flybys. What about Cassini-Huygens? If there is some press release or newspaper reporting that is making this claim, then we should repeat it here regardless. However, If that's the case then this sentence needs a citation. Claims of fact such as this should be cited regardless though, which is why I've added the citation needed tag in addition to the dubious tag.
— V = IR (Talk • Contribs) 03:45, 16 July 2011 (UTC)
Cassini hasn't orbited any moons. That would be like saying Cruithne is a satellite of the Earth. They were all flybys. It's never been captured by the gravitational field of a moon, and then broken free.
I've put the statement back in the lead. It's a key demonstration of the ion drive, which is the real purpose of the mission. (Or at least the purpose that got the funding.) It's therefore a key aspect of the mission. — kwami (talk) 02:46, 29 August 2011 (UTC)
Any particular reason why Dawn is witten with italics in the article's name and throughout the article? Cheers, BatteryIncluded (talk) 00:18, 29 August 2011 (UTC)
in the following section irrelevant explanation to relevant obfuscation. [6]
Dawn carries a computer chip bearing the names of more than 360,000 space enthusiasts.[1] The names were submitted online as part of a public outreach effort between September 2005 and November 4, 2006.[2] The microchip (about the size of a United States nickel coin) was installed on 17 May 2007 above the forward ion thruster, underneath the spacecraft's high-gain antenna.[3] More than one microchip was made, with a back-up copy on display at the 2007 Open House at the Jet Propulsion LaboratoryinPasadena, California.
Dawn has apparently departed for Ceres:
http://news.yahoo.com/dawn-craft-depart-asteroid-dwarf-planet-090107827.html
As the wikibox is somewhat unique, any suggestions on how to format the orbital information. Is it more appropriate to say Vesta (former) or should we put a time range that it was orbiting Vesta? In the latter case, does anyone know of a source that gives more exact arrival and departure times than the Yahoo article? - Sangrolu (talk) 12:50, 5 September 2012 (UTC)
What might happen after 3 months at 375km Ceres orbit ? Will it go lower ? Rod57 (talk) 11:57, 3 December 2014 (UTC)
Does this: "while images taken of Pluto by New Horizons will exceed the resolution of the Hubble telescope by approximately May 5, 2015" serve any purpose in the article? Bubba73 You talkin' to me? 07:10, 4 February 2015 (UTC)
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This could have very well spilled over into an edit war. An anonymous user has apparently gone rampant again, but this time the edits seem constructive and I copyedited them. However, the user is insistentontheir style of formatting and has reverted even my rollbacking, clearly unaware that having direct quotations "paraphrased and properly cited" is not enough for an article – close paraphrasing, like I saw with their version, is unacceptable. What should be done? I can deduce from the talk page that said anonymous editor steadfastly refuses to accept others' viewpoints. Parcly Taxel 07:04, 17 February 2015 (UTC)
So, no possibility of a Pallas flyby in 2018 or so? Maybe we could mention that? — kwami (talk) 00:55, 26 February 2015 (UTC)
Here are another two mission journal references [9][10]. As per the mission team:『Pallas was never part of our plan. Indeed, we have never even taken a serious look at it. I don’t know quite how the story originated. It may have been a desire by some people, but no meaningful mission analysis ever supported it. 』 Ttwaring (talk) 14:57, 10 March 2015 (UTC)
Going over those announcements, I was reminded that all the hoopla about Dawn visiting a DP is incidental: the intent was to study the large bodies (protoplanets) of the belt, and if Pallas wasn't feasible, Vesta + Ceres would hopefully be enough to "bracket the properties of large minor planets". (There was similar hoopla about Vesta being a "real world" when it was visited.) That particular paper was all about comparing these three bodies, and Hubble time was devoted to Pallas to provide info on the missing member of the trio, so I changed the lead to say Dawn is visiting two of the three (known) protoplanets in the belt. Also, the mission was only able to get funding because of the return from developing a new form of propulsion. We tend to overlook the drive now, but that really belongs in the lead, as part of a dual mission. — kwami (talk) 23:24, 10 March 2015 (UTC)
To quote: (CNN) NASA's tractor-trailer sized Dawn spacecraft will snuggle up to Ceres on Friday, getting close enough to be pulled into orbit and to complete the first mission to a dwarf planet. "I'm just delighted that Dawn is now on the doorstep of Ceres," Jim Green, director of NASA's planetary science division said in a news conference on Monday. Ceres was discovered in 1801 (Pluto wasn't found until 1930) and was the first object found in our solar system's main asteroid belt between Mars and Jupiter. ... ... ... [As you all know, right?]
Headline-1: NASA spacecraft nearing mysterious dwarf planet Ceres
QUOTE: "Ceres was demoted to an asteroid because 19th century astronomers couldn't be sure it was round. But it was bumped up to a dwarf planet when that category was created in 2006." -- AstroU (talk) 13:32, 3 March 2015 (UTC) -- PS: FYI for future editing.
I believe the 'SLOOH' observatory community will have a 'live' broadcast and commentary tomorrow, Friday 3-6-2015.[11] Are there alternative websites for the Ceres event?
It starts at 10am tomorrow (Friday): http://live.slooh.com/stadium/live/dawn-to-arrive-for-ceres
-- AstroU (talk) 02:08, 6 March 2015 (UTC) -- PS: Maybe it will be just commentary at 'SLOOTH.com'
Will Dawn have to fire its engines to enter orbit of Ceres, or will Ceres' gravity capture it? Bubba73 You talkin' to me? 02:42, 6 March 2015 (UTC)
A very interesting and informative article in an Aviation Week news flash [12] -- Read the reader comments also. -- AstroU (talk) 16:31, 6 March 2015 (UTC)
However, gravity also had a role. Gravity and spaceship propulsion (forces) were balanced. Spaceship propulsion was controlled from JPL to counterbalance Ceres gravity. -- Charles Edwin Shipp (talk) 19:49, 7 March 2015 (UTC) -- PS: Thanks for the link at space.com (just above) that explains with computer animation, "JPL gracefully approached into orbit", to loosely quote.
![]() | This page is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
The comment(s) below were originally left at Talk:Dawn (spacecraft)/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.
October 2007 - Up-rated to B-Class since it is reasonably comprehensive, has good use of images, and is well referenced with in-line <ref>-tagged citations. (sdsds - talk) 00:18, 13 October 2007 (UTC)
== Update Dawn Mission extended 40 days at Vesta == Dawn Mission's observations of Vesta extended for 40 days, August 26, then arrive at Ceres as scheduled in February 2015. http://dawn.jpl.nasa.gov/news/index.asp — Preceding unsigned comment added by Bobdeloyd (talk • contribs) 19:12, 22 April 2012 (UTC) |
Last edited at 19:13, 22 April 2012 (UTC). Substituted at 14:38, 1 May 2016 (UTC)