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Sept. 2002 Asteroid/Comet News
Updated: 13 July 2004
<<August 2002 News ^UP^ October 2002 News>>
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4 September 2002
Space.com has a 4 Sept. report on an article in the next day's issue of Nature by Stephen M. Slivan of MIT about his continuing research on the spin relationships of the Koronis family of asteroids. This family is believed to consist of 200-plus remnants from an ancient collision of two asteroids, and includes among its members 243 Ida and its satellite 243 (1) Dactyl. What is remarkable, Slivan reports, is that, instead of the random chaotic motion that should theoretically result from an enormous collision, he has found in a small sampling what appears to be a clustering of spin rates and another clustering of spin axis orientations.
The Isaac Newton Group (ING) of Telescopes on the Canary Islands of Spain issued a 4 Sept. news release with images and a movie of 2002 NY40 captured with its 4.2m William Herschel Telescope. These observations were in the near-infrared using adaptive optics on the night of the 17th and 18th when NY40 was at about two lunar distances and still approaching Earth. The resolved cross-section of the tumbling asteroid appears to be 400 meters/yards or less. There are reports at Astronomy.com 5 Sept., BBC 4 Sept., and Space.com 4 Sept.
Up through August, SWAN discoveries were discussed on the officially conducted SOHO chat about what's in view. When XingMing Zhou on 2 Sept. reported an object in SWAN images for 13-19 Aug., however, the response from SOHO staff two days later was, "we don't deal with SWAN comets here. Take those discussions to the Yahoo newsgroup sohohunter" (sohohunter requires registration). This follows the delayed IAU naming of comet C/2002 O6 as SWAN rather than SOHO. It and two other SWAN discoveries, which remain unnamed by the IAU, are tallied by the joint ESA/NASA mission as SOHO-93, -429, and -497 (see A/CC's report), but those apparently will be the last to mess up the mission's name-numbering system, which the IAU doesn't recognize.
5 September 2002
A fireball was seen the night of 5 Sept. in the skies south of Adelaide in South Australia. The Australian Broadcasting Corp. posted two reports on 6 Sept., with the second saying that a search for remnants was about to begin. See 6 Sept. reports at Space.com and CNN.
A 5 Sept. European Space Agency news release explains the critical timing for the launch of the Rosetta mission next January from South America in order to meet comet 46P/Wirtanen in 2012. Rosetta will do flybys of Mars and Earth during its gravity assist maneuvers.
6 September 2002
(updated 4 Dec.) A fireball was seen across Colorado and neighboring states at 8:32pm local. Chris Peterson's report says the meteor may have skipped back into space, and that this "event was captured on video, and a complex acoustic signal was recorded by at least one infrasound monitoring station." See KMGH-TV Denver's 6 Sept. report.
A Lawrence Livermore National Lab news release of 6 Sept. reports an article in the same day's issue of the journal Science by Ian Hutcheon, Yuri Amelin, Alexander Krot, and Alexander Ulyanov. The title is "Pb Isotopic Ages of Chondrules and Ca-Al Rich Inclusions," and it dates calcium aluminum-rich inclusions (CAIs) found in chondritic meteorites to 4.57 billion years, several million years older than chondrules. Both were building blocks in the early Solar System nebula on the way to forming planetesimals and planets over the following 50 million years or so.
See also the 30 Sept. 2002 "Using Aluminum-26 as a Clock for Early Solar System Events" PSR Discoveries article.
7 September 2002
5th IAA Intl. Conference on Low-Cost Planetary Missions, first announcement for the 24-26 Sept. 2003 gathering at ESA headquarters in Noordwijk, Netherlands, sponsored by ESA & the International Academy of Astronautics (IAA)
13 September 2002
ESA reported that the Rosetta spacecraft had been flown from Europe to the Kourou Spaceport in South America.
MPEC 2002-R69 of 13 Sept. reports the recovery of comet P/1986 A1 (Shoemaker 3), aka 1985 XVIII, 1986a, and 2002 R2. It was spotted on 9 Sept. at Saji Observatory in Japan by T. Oribe. Seiichi Yoshida has finder charts. It now (as of 19 Sept.) has been numbered as comet 155P.
19 September 2002
On 19 September the IAU Minor Planet Center updated its asteroid Discovery Circumstances and Periodic Comet Numbers pages. There were two new comet numberings (154P/Brewington and 155P/Shoemaker 3), and 1,869 new asteroid numberings, now topping out at 48380 5622 T-3. One of the new numberings is 47171 1999 TC36, the first TNO/Plutino discovered to be binary.
There were 84 new asteroid namings, from 6983 Komatsusakyo (1993 YC) to 43669 Winterthur (2002 GA10), which becomes the highest numbered publicly-named asteroid. Among other new names are 43511 Cima Ekar (2001 CP48), and OCA-DLR Asteroid Survey discoveries 16984 Veillet (1999 AA25) and 17744 Jodiefoster (1998 BZ31).
There also were five changes adding Eugene Shoemaker to newly-named discoveries originally credited only to Carolyn Shoemaker, and 688 changes involving NEAT credits, changing "JPL/GEODSS NEAT" to just "NEAT" for discoveries made at Haleakala and Palomar.
20 September 2002
The SOHO "Hot Shot" for 20 Sept. shows C/2002 S2 (SOHO-517) diving into the Sun, furiously boiling off water as seen with the SOHO LASCO and UVCS instruments. This Kreutz-group comet's discovery is credited to Sebastien Hoenig observing near-realtime 17 September images online from the LASCO C3, and is reported in MPECs 2002-S17 and 2002-S36.
25 September 2002
A fireball flew over and may have impacted near the settlement of Mama in the northern Irkutsk region of Russian Siberia. News of this first reached the outside world eight days later. See A/CC's report about the series of news developments the came during October.
26 September 2002
A Carnegie Institution news release of 26 Sept. about how to store molecular hydrogen (H2) in ice and water says that among the ramifications is that "hydrogen might exist in icy bodies in our solar system that we thought were incapable of retaining it."
Workshop on Scientific Requirements for
Mitigation of Hazardous Comets & Asteroids (3-6 Sept. 2002 & 4 Feb. 2003)
In advance of the 3-6 Sept. Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids held in Arlington, Va., Florida Today on 31 Aug. published three articles summarizing the area of discussion: the debate, the observation effort, and the odds. There is a nice accolade to the unfunded "amateurs" who comprise a large and critical part of the observing effort. Also mentioned is the part of the hazard problem generally less mentioned, comets coming in from very deep space. Clark Chapman of Southwest Research Institute is quoted as saying, "To satisfactorily find comets in time to do anything about it is a major challenge. . . It would maybe involve [putting] telescopes out in Jupiter's orbit."
Reuters/MSNBC did a brief 3 Sept. report ahead of the the workshop. UPI's 5 Sept. story about the military viewpoint reports that General Pete Worden of the USAF Space Command says, "The Department of Defense is developing a NEO information clearinghouse and warning center as part of the existing missile warning and space object tracking complex in Cheyenne Mountain, Colo." Sky & Telescope's 6 Sept. report on the Workshop concentrates on the subject of how to report hazards to the public. Workshop host NOAO issued a summation news release on 6 Sept.. UPI has a 6 Sept. summary report, as does Florida Today 7 Sept..
The 3 Sept. edition of Cambridge Conference Correspondence has abstracts from the workshop's presentations. Many of these delve into topics of interest to exploring minor objects in general, hazardous or not. This collection is a lengthy must-read that ranges too widely to neatly characterize here. There is operating in low-gravity environments, imaging the interiors of asteroids, and much more. One example is a proposal from Ball Aerospace to build a small fleet of microsatellite-style probes to send out to explore NEOs as primary or secondary launch payloads. Another example is Clark Chapman's abstract on "What we know and don't know about asteroid surfaces." It says that the considerable literature concerning asteroid regoliths (mostly published in the 1970s and 1980s) based on theoretical extrapolation from lunar regolith models and on inferences from what are termed "regolith breccia" meteorites [was] proved wrong [by the] NEAR Shoemaker mission to Eros. . . In terms of self-gravity, the multi-hundred-meter body we might want to deflect from Earth impact is as different from Eros as Eros is from the Moon.
The workshop was held by the National Optical Astronomy Observatory (NOAO) and is sponsored by NASA and cosponsored by Ball Aerospace and Science Applications International Corp. This last, SAIC, was reported by Space.com 5 August to have recently delivered to the U.S. Space Command a report about having the U.S. military play a more central role in monitoring hazardous objects.
Mitigation workshop headlines
- The 3 Sept. Cambr. Conf. Correspondence has a compilation of workshop abstracts
- "Asteroid experts say we're not ready," Reuters wire on MSNBC, 3 Sept.
- "Scant support for turning aside doomsday asteroid," Reuters wire on CNN, 5 Sept.
- "Near-Earth object research deemed vital," 6 Sept. UPI wire
- "Military takes asteroid threat seriously," 5 Sept. UPI wire
- "Assessing and Reporting Impact Risks
," 6 Sept. Sky & Tel. article
- "Science Workshop Reveals Evolving Perspective on Asteroid Threat," NOAO 6 Sept. news release
- "Asteroid defense system in the works," AP wire on MSNBC 6 Sept. (see the last paragraph)
- "Experts: Slim Chance Asteroids Hitting Earth But Vigilance Needed," AP wire on Space.com 7 Sept.
- "Scientist study how avoid asteroid strike," 7 Sept. Fla. Today article
- Ed Grondine's report to Cambridge Conference Correspondence, 17 Sept., which, among many things said, includes notes about the science presented and about Gen. Pete Worden's efforts, and also says, members of the Congress are waiting for a report on the impact hazard from a Federal agency separate from NASA, the results of which are to be to delivered in 2003.
- "Watch out for earthbound asteroids," Wall Street Journal article on MSNBC 20 Sept.
Some of the above reports mention the proposed Large-aperture Synoptic Survey Telescope (LSST) as a solution to completing a census of near-Earth asteroids down to perhaps 300 meters/yards in size. That project has its own Web site at www.lsst.org.
4 February 2003 report release
Military NEO effort proposed
The Billy Mitchell of NEOs (8 September 2002)
Brigadier General (and PhD astronomer) Pete Worden is beginning to look like the "Billy Mitchell of NEOs," although apparently without Mitchell's legendary abrasiveness. Most news reporting until now has portrayed Worden's opinions on NEO subjects as only personal thoughts and not positions of the U.S. Space Command, where he is a deputy director. So it is interesting to visit the U.S. Air Force's home page at http://www.af.mil, where, in the top right-hand "Air Force News" column, you will currently find, "Near-Earth objects pose threat, general says."
This Air Force-written story, dated 6 September, centers not on last week's NASA hazards mitigation workshop, where Worden also participated (see UPI's report), but on his testimony to the "congressionally mandated Commission on the Future of the U.S. Aerospace Industry." It doesn't appear that this testimony has been posted yet to the commission's Web site, but the general was on the agenda for its 22 August meeting, and there is another meeting coming up on 17 September (see the commission's reports and meetings pages).
The article says that Worden recommended to the commission that a natural impact warning clearinghouse could be formed by adding no more than 10 people to current U.S. Space Command early warning centers. This organization would catalog and provide credible warning information on future NEO impact problems, as well as rapidly provide information on the nature of an impact. In order for this clearinghouse to provide accurate information, NEOs must first be detected, cataloged and their orbits defined.
Such an activity would at a minimum seem to overlap, if not duplicate, the work of the International Astronomical Union Minor Planet Center, NASA/JPL NEO Program, and University of Pisa NEODyS program, which among themselves have almost ten full-time employees. But, According to Worden, this does not mean other groups, in particular the international scientific community, should not continue their independent efforts. But the United States is likely, for the foreseeable future, to have most of the required sensors to do this job. He added that DOD has the discipline and continuity to ensure consistent, long-term focus.
His clearinghouse concept is what has been getting the attention, but, to accomplish its goals, Worden will also have to push for the ground- and space-based military resources needed to find the "hundreds of thousands" of NEOs of a size on the order of 100 meters/yards wide. This is well beyond the current official NEO cataloging goals (and abilities) of the IAU, Congress, NASA, and wider NEO community.
Involving the military wouldn't be anything new, of course. Most NEO discoveries today are already being made from U.S. military installations with military hardware, mainly LINEAR in New Mexico as well as the Hawaiian telescope used by JPL's NEAT program. And most atmospheric event detections are being made with U.S. military ground sensors, and with satellites that were under Worden's command during 1994-96.
Will we someday be talking about military-designated minor objects? Doing its own cataloging would allow the Space Command to publish discoveries and orbits as "sanitized" information without having to divulge details about the classified "technical means" used to gather the data. One can speculate this might include giving the military a way to employ already existing resources that have immediate potential for NEO searches but, for security reasons, won't report data to civilian astronomers.
It does seem a stretch to imagine today's informal worldwide network of professional and amateur astronomers all uploading their nightly observations to Cheyenne Mountain instead of Harvard. However, if the military doesn't take on some cataloging duties, how will the civilian cornerstones of today's NEO monitoring deal with doublings of the number of known minor objects? NEODyS and the JPL NEO Program currently watch NEOs counted by hundreds. And the underfunded IAU MPC is already on overload from keeping track of about 50,000 fully cataloged comets and asteroids plus several hundred thousand partially cataloged objects.
The future workload growth isn't coming just from possible military surveillance, but also from new observation capabilites of many kinds. ESA's Gaia mission, set to begin in eight years, for instance, is alone predicted to be capable of discovering 30 to 40,000 new objects per year for five years.
The chair of the IAU Working Group on NEOs, David Morrison, is on record (SpaceRef.com 16 July 2002) as completely dismissing any urgency in searching for the same objects that Worden says are actually the biggest near-term threat and represent "critical national and international security issues." Which brings us back to this: Who was Billy Mitchell? He was a distinguished but controversial U.S. Army Signal Corps Brigadier General who campaigned in the 1920s for reorganizing the U.S. military around air power. He sank a few U.S. Navy battleships and then his own career, but his campaign ultimately helped lead the U.S. military and aviation establishment to be better prepared for WW-II, even if caught by surprise when the attack on Pearl Harbor happened much like Mitchell had warned. (Here is a good starting place for learning more about Mitchell.)
One might initially think, by the way, that the expressed military interest is only in NEOs and not other minor objects. However, you can't sort out dangerous from safe objects without tracking them all. Searching for NEOs sweeps up many others, anyway; witness how NEAT routinely discovers Centaurs out past Jupiter. And, since one of the most dangerous gaps in NEO warning has to do with unknown inbound comets, it would only be a short leap of purpose to extend the U.S. Air Force's mandate all the way to the Oort Cloud, halfway to the next star.
For more on these topics, see several reports archived under Planetary defense, as well as Space.com's 5 August report on an outside study done for the U.S. Space Command about setting up a clearinghouse, and UPI's 5 Sept. report on military NEO interest. The BBC has a 9 Sept. report based on the Air Force article, as does Astronomy.com on 15 Sept. and Time magazine 17 Sept.. SpaceDaily ran the original Air Force article whole, redated 17 Sept..
A footnote: The U.S. Army Signal Corps could be said to have been the "space command" of its time. It dealt with balloons as early as the Civil War, spanned desert territories and frozen wilderness with telegraph communications, helped develop many new technologies, and, beginning in 1907, was assigned the operation of dirigibles and airplanes. Aviation was split off from the Signal Corps at the end of World War I to evolve in name, organization, and independence within the Army until becoming the separate U.S. Air Force in 1947, home of today's Space Command.
Why so many EKBO binaries?
An article by Alan Stern of the Southwestern Research Institute, to appear in the Oct. 2002 Astronomical Journal, prompted these September headlines:
The above reports mention the coming infrared space telescope, SIRTF. See that mission's home page for more info. And see the Binary minor objects topic for more about EKBO binaries.
Recent IAU/MPC circulars report on confirmations of earlier binary detections. MPEC 2002-R65 of 12 September reports on 2001 QT297, IAUC 7962 of 29 August updates 2000 CF105, and IAUC 7959 of 27 August reports on 1997 CQ29.
J002E3 wandering Apollo relic?
An object first spotted 3 Sept. by William K. Yeung was posted to the Minor Planet Center's NEO Confirmation Page on the 4th with the designation J002E3, and was removed two days later with only the cryptic comment, "not a minor planet." On the 11th it was reported that J002E3 is in Earth orbit and may be a Saturn rocket stage, or, less likely, a captured asteroid. JPL's 19 September analysis is that it is the S-IVB stage from Apollo 12, the second lunar landing mission, and that it will mostly likely escape to solar orbit again rather than hit the Moon or re-enter Earth's atmosphere.
October 2003 & later updates:
The JPL NEO Program issued a 9 Oct. update on J002E3, saying that a 16 June 2002 precovery image has been found, and that the object has been showing slight orbital changes explained by solar radiation pressure on a spent rocket stage. It is now certain that J002E3 will depart the Earth-Moon system in June 2003 and that there is no possibility of an impact for several decades. In the years ahead J002E3 may be recaptured, but the first opportunity for this will not be until the mid-2040s. Space.com has a 11 Oct. report.
See Mark Kidger's J002E3 page for some collected information.
The September headlines: (newest first)
- "Rocket Scientists Find a Rocket," 25 Sept. Wired News article
- "New 'moon' to leave Earth orbit," 23 Sept. CNN article
- "Long-lost Apollo rocket returns to earth orbit," 21 Sept. ABC Australia article
- "Mystery Object Orbits Earth," 20 Sept. Science@NASA article
Could it be an alien spaceship? "If it is," says Chodas, "the aliens aren't good pilots. J002E3 is in a chaotic orbit. It loops around Earth once every 48 days or so, coming as close to our planet as the Moon and ranging as far away as two lunar distances." There's no evidence that the speck is moving under its own power.
See also "Mystery Object J002E3 Gallery" at SpaceWeather.com.
- "Apollo 12 rocket returns to Earth orbit," Reuters wire on CNN 20 Sept.
- "First Confirmed Capture into Earth Orbit Is Likely Apollo Rocket," 20 Sept. JPL news release
- "MIT astronomers ID object as Apollo stage," MIT 19 Sept. news release
- "New Space Junk Satellite Will Leave Earth's Grasp," 19 Sept. Space.com article, also on MSNBC as "Junk satellite just passing through"
- "Orbiting Apollo rocket will soon depart," 19 Sept. New Scientist article
- "New Clues in the Continuing Detective Story of J002E3," JPL NEO Program News 19 Sept.
- "Painted Moon," 19 Sept. Astronomy.com article
- "Space relic returns to home planet," UPI wire 18 Sept.
- "Paint Confirms Earth's New Satellite Not an Asteroid," 18 Sept. Space.com article
- "UA Astronomers Discover That Earth's Second Moon Wears Apollo Paint," Univ. of Arizona 17 Sept. news release
- "Scientists Hope to Monitor Space Junk Hitting Moon," 16 Sept. Space.com article, also on MSNBC as "Space junk could be scientific gem"
- "See the Space Junk that Might Hit the Moon," 16 Sept. Space.com article
Links: Fort Bend Astronomy Club & its A-Team
- "Asteroid hunter apparently finds Apollo-era rocket," AP wire on Florida Today 13 Sept.
- "Newfound 'moon' could be Apollo rocket junk," 13 Sept. CNN article
- "Earth's new 'moon' is space junk," 12 Sept. BBC article
- "Orbit shows "second Moon" may be Apollo junk," 12 Sept. New Scientist article
- "Astronomers wrangle over Earth's 'new moon'," AFP wire on SpaceDaily 12 Sept.
- "Earth's Newest Satellite Could Hit Moon Next Year," 12 Sept. Space.com article
- "Newly Discovered Object Could be a Leftover Apollo Rocket Stage," JPL NEO Program News 11 Sept.
- "Newfound Object Orbiting Earth is Likely Apollo Junk," 11 Sept. Space.com article, also on MSNBC as, "Is mystery object merely space junk?"
- "Sequence of J002E3 'Mystery Object'," images from Arkansas Sky Observatory, 11 Sept. (Contrary to other reports, this one says that J002E3 was "noted to definitely be slightly variable in brightness.")
- "Earth's Newest Moon?
," 11 Sept. Sky & Telescope article
- "New 'moon' found around Earth," 11 Sept. BBC article
- Asteroid hunter's once in a blue moon find," 11 Sept. Guardian article
- "Mystery Object," Sky & Telescope AstroAlert 10 Sept., as posted to Arkansas Sky & NASA/SSE
Some of the above reports allude to various objects with orbits closely related to Earth's. See Asteroids sharing Earth's orbit for specific references to those objects (with further links), including a few others that may be Saturn rocket stages.
Comet breakups
There was news during September about an article by Zdenek Sekanina of JPL in the 10 Sept. 2002 Astrophysical Journal about what sungrazers reveal about how comets break up.
For more about sungrazers, see SOHO. Among many recent non-SOHO comet breakups, see C/2002 Q2 and Q3-A/B/C below.
ESA's NEO effort
2003 ESA NEO news
ESA had a news release 26 March 2003 about mission proposals to help answer essential questions on the NEO threat, such as how many there are, their size and mass, and whether they are compact bodies or loose rock aggregates. . . These phase A studies by industry and academia, which were completed in January 2003 . . . will now be discussed within the Agency and with ESA's international partners.
See also the ESA NEO Space Mission Preparation page, issue #19 of the online publication, Tumbling Stone, dated 24 March 2003.
Delay in MUSES-C asteroid sample return mission
- "MUSES-C Launch Put Off," 26 Sept. ISAS statement
In spite of this launch delay . . . [from December] till the next launch window (May 2003) . . . arrival times to the asteroid and the earth will not be changed.
Note: This information didn't reach many space news sites until mid-October, when there was a flurry of reporting based on the September statement, but nothing new.
- "MUSES-C launch delayed," 26 Sept. SpaceToday.net news brief
- More about MUSES-C & its destination, 25143 1998 SF36
CU New Horizons student dust counter
(updated & revised) A 23 September news release from the University of Colorado at Boulder (CU) reported that the school's Laboratory for Atmospheric and Space Physics (LASP) and astronomy/physics and aerospace engineering students were proposing a dust counter to be added to the New Horizons mission to Pluto and the Kuiper Belt. At the time it was in doubt whether the mission itself would proceed, an issue that was still open when an announcement was made December 17th that the proposal had been accepted. Finally, in early April, it was reported that the mission had been given a full go-ahead, complete with dust counter. As the mission's chief scientist, Alan Stern, was quoted in the September news release, "Students have never before built and flown a research, education and outreach device for a NASA deep space mission."
Headlines (newest first)
Deep Ecliptic Survey August observations
Lowell Observatory's Deep Ecliptic Survey (DES) has turned in another large batch of results. MPECs 2002-S49, 2002-S50, and 2002-S51 of 26 Sept. announce 14 new discoveries, with most ranging in semimajor axis from 42.25 to 46.11 AU, and several between 37 and 38 AU. All were discovered during 9-11 Aug. with the Blanco 4m telescope at Cerro Tololo, most on the 11th, and some follow-up work was done with the 3m at Mt. Hamilton.
Another 15 objects were updated by DES in MPECs 2002-S44, 2002-S45, and 2002-S46 of 24-25 Sept., all with semimajor axes of 39.05-46.0 AU except one at 51.35 AU. All of this was done with the same two telescopes during 29 July to 11 Sept., mostly at Cerro Tololo.
5 Oct. update: During this work another object was discovered on 12 Aug. by Marc Buie et al. with the Cerro Tololo 4m Blanco telescope. It was followed up 10-11 Sept. with Lick Observatory's 3m telescope on Mt. Hamilton, and spotted again with Lowell's Anderson Mesa 1.8m telescope on 4 Oct. The result is MPEC 2002-T24 of 5 Oct. for 2002 PQ152, with a lowly-inclined orbit initially calculated to run from 20.04 to 41.52 AU. With a semimajor axis of 30.78 AU, PQ152 seems to fit into the Centaur category of distant minor objects.
Risk concerns removed during September
Potentially hazardous asteroids removed from the NEODyS and/or JPL risk pages during September 2002 include: 2002 QF15, 2002 RA126, 2002 RC117, 2002 RS28, 2002 RZ125, and 2002 SM.
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