Contents on 11 June '07
- Minor-Object News -- five items
- Minor-Object Science -- four papers
- IAU Minor Planet Center
- Impact Risk Monitoring -- one object reported
WELCOME to A/CC's prototype daily news publication designed to be the viewing end of a planned autonomous 24-hour news service. The new tools and this publication format are working well enough now to share with readers. It is expected that this approach will require less time to maintain than our previous news and small asteroid pages, which were retired on May 14th. There's still more development ahead and there probably will be some glitches along the way, but this is what's needed to keep up with the increasing pace of minor-object news. The CRT page will be maintained separately for a little while longer, until all of this is working smoothly. And the CRT and small-asteroid ephemerides will be kept going.
Minor-Object News on 11 June '07
- "Geologists to name 'new' meteorite crater after Havre couple," Havre Daily News 11 June - Quote: "[The Benders] had been using Google Earth to locate fossil hunting grounds when "dumb luck" led the satellite view to scan over a formation familiar, yet very exciting ... just southeast of Thornhill Butte."
- "Was blinding light a meteor?" Daily News 11 June - Quote: "The object which spewed a blinding light that lit the night skies in several areas of the North Western Province on Sunday [around 9.05 p.m.] is suspected to be meteor. The light was accompanied by huge booming sounds."
- Site schedule note: These pages will be on no regular schedule, and sometimes delayed, during the rest of June due to travel.
- Scientific papers: Today's selection of papers posted to arXiv.org contain some of particular interest (see listings below). For starters, De Luise et al. (including Boattini, Valsecchi, Milani, and Rossi) report their analysis of 144898 2004 VD17. They state that this optically well-observed object still has "a possibility of impacting the Earth (in the year 2102), compatible with the available astrometry" and this risk "cannot be easily removed by additional astrometry" and "no radar observations are possible for a long time," so it is important to better understand its physical characteristics. They approached this using large telescopes in Chile last year, cutting this object's diameter estimate down to 320 meters, but finding a fast rotation rate that could indicate a monolithic rather than "rubble pile" structure. No companion was found, so density cannot be directly measured. 144898's reflection spectrum was found to have a good meteorite match, appearing to confirm a composition of enstatite, which is a pyroxene with a magnesium silicate base.
Another paper, by Collins and Sari, hits close to home in a different way, tackling the abstract concept of how protoplanets can share orbits in early planetary systems. Not mentioned is a specific possible example in our own backyard. Two theories about how the Earth-Moon system formed -- capture and giant impact -- require relatively low-energy encounters. Thus the embryonic Moon or the Mars-size impacting object had to have formed in resonant orbits very close to Earth's, or actually in Earth's own orbit at either the Earth-Sun L4 or L5 Lagrange point. See Belbruno and Gott's 2005 paper, Where did the Moon come from? and Space.com's 2004 report for more about the co-orbital impact theory. Harrison Schmitt, the only geologist to walk on the Moon, has been a proponent of the capture theory (see, for instance, a 2000 PDF abstract).
- Meteorite books: The London Geological Society Lyell Collection has posted chapters in PDF form from two books, one about meteorites and the other related to prehistoric Earth impacts, and has made these PDFs available for free download (only) until June 18th. The books are the 2006 The History of Meteoritics and Key Meteorite Collections: Fireballs, Falls and Finds and 2007 Myth and Geology. The first includes articles on the history of desert and Antarctic meteorites and on various meteorite collections, including a "A brief history of the Vatican meteorite collection" by Guy J. Consolmagno. Articles on contemporary meteorite studies include "Meteorite provenance and the asteroid connection" by Alan J. Bowden, telling about efforts to link individual meteorites to specific asteroids.
The second book is described as "the first peer-reviewed collection of papers focusing on the potential of myth storylines to yield data and lessons that are of value to the geological sciences [and] challenges the widespread notion that myths [lack] value for the physical sciences." Three of its articles tackle subjects such as "cosmic impacts and massive Plinian eruptions in Holocene South America," evidence for a "cosmogenic mega-tsunami in the Australia region," and "meteorite records in the ancient Greek and Latin literature."
This timely tip comes from postings June 9th to the Metorite Mailing List which were brought to A/CC's attention by Ed Grondine, author of Man and Impact in the Americas (more info).
Minor-Object Science on 11 June '07
- "Physical Investigation of the Potentially Hazardous Asteroid (144898) 2004 VD17" by De Luise, F. with D. Perna, E. Dotto & 9 others, abstract & PDF at arXiv.org 11 June - Quote: "In this paper we present the observational campaign carried out at ESO NTT and VLT in April and May 2006 to investigate the nature and the structure of the Near Earth Object (144898) 2004 VD17. In spite of a great quantity of dynamical information, according to which it will have a close approach with the Earth in the next century, the physical properties of this asteroid are largely unknown. We performed visible and near-infrared photometry and spectroscopy, as well as polarimetric observations. Polarimetric and spectroscopic data allowed us to classify 2004 VD17 as an E-type asteroid. A good agreement was also found with the spectrum of the aubrite meteorite Mayo Belwa. On the basis of the polarimetric albedo (p_v=0.45) and of photometric data, we estimated a diameter of about 320 m and a rotational period of about 2 hours. The analysis of the results obtained by our complete survey have shown that (144898) 2004 VD17 is a peculiar NEO, since it is close to the breakup limits for fast rotator asteroids, as defined by Pravec and Harris (2000). These results suggest that a more robust structure must be expected, as a fractured monolith or a rubble pile in a "strength regime" (Holsapple 2002)."
- "From mean-motion resonances to scattered planets: Producing the Solar System, eccentric exoplanets and Late Heavy Bombardments" by Thommes, Edward W. with Geoffrey Bryden, Yanqin Wu & Frederic A. Rasio, abstract & PDF at arXiv.org 11 June - Quote: "We show that interaction with a gas disk may produce young planetary systems with closely-spaced orbits, stabilized by mean-motion resonances between neighbors. On longer timescales, after the gas is gone, interaction with a remnant planetesimal disk tends to pull these configurations apart, eventually inducing dynamical instability. We show that this can lead to a variety of outcomes; some cases resemble the Solar System, while others end up with high-eccentricity orbits reminiscent of the observed exoplanets. A similar mechanism has been previously suggested as the cause of the lunar Late Heavy Bombardment. Thus, it may be that a large-scale dynamical instability, with more or less cataclysmic results, is an evolutionary step common to many planetary systems, including our own."
- "Co-orbital Oligarchy" by Collins, Benjamin F. with Re'em Sari, abstract & PDF at arXiv.org 11 June - Quote: "In this work we examine the interactions of a moderate number of protoplanets in an oligarchic configuration and find that neighboring protoplanets stabilize co-orbital systems of two or more protoplanets. We present a new picture of oligarchy in which each part of the disk is not ruled by one but by several protoplanets having almost the same semi-major axis."
- "Evolution of interstellar dust and stardust in the solar neighbourhood" by Zhukovska, Svitlana with Hans-Peter Gail & Mario Trieloff, abstract & PDF at arXiv.org 11 June - Quote: "It is shown that the interstellar dust population is dominated by dust accreted in molecular clouds; most of the dust material entering the Solar System at its formation does not show isotopic abundance anomalies of the refractory elements, i.e., inconspicuous isotopic abundances do not point to a Solar System origin of dust grains."
NEOCP Activity on 11 June '07
The MPC's NEO Confirmation Page has 5 listings: 4 new, 1 updated
When last checked at 2357 UTC today, the Minor Planet Center's NEO discovery Confirmation Page (NEOCP) had four new and one updated listings. Of these, four were "one nighters."
New MPECs on 11 June '07
Minor Planet Electronic Circulars
There were eight MPECs issued this day from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.
- MPEC 2007-L37 time-stamped "06:07 UT" - Daily Orbit Update - see below
- MPEC 2007-L38 time-stamped "09:29 UT" - 2007 LS - see below
- MPEC 2007-L39 time-stamped "09:31 UT" - 2007 LT - see below
- MPEC 2007-L40 time-stamped "09:34 UT" - 2007 LU - see below
- MPEC 2007-L41 time-stamped "09:37 UT" - 2007 LV - see below
- MPEC 2007-L42 time-stamped "14:49 UT" - Comet C/2007 K6 (McNaught) - see below
- MPEC 2007-L43 time-stamped "15:27 UT" - 2004 VS60 - see below
- MPEC 2007-L44 time-stamped "15:30 UT" - 2007 JF22 = 2007 AL
MPEC 2007-L44 - "15:30 UT" - 2007 JF22 = 2007 AL
- K07J22F 2007 JF22 (Q=4.906 AU, H=16.1 ~2.04 km, q=1.293 AU)
MPEC 2007-L43 - "15:27 UT" - 2004 VS60
- K04V60S 2004 VS60 (H=18.2 ~776m) from Mt. John Obs. (May 18.44-48p6 & June 11.36-39p5)
MPEC 2007-L42 - "14:49 UT" - Comet C/2007 K6 (McNaught)
- CK07K060 C/2007 K6 (McNaught) (i=105.2°, q=3.436 AU, TP=2007 July 5.192 TT) from Mt. John Obs. (June 10.75p3)
MPEC 2007-L41 - "09:37 UT" - 2007 LV
- K07L00V 2007 LV (H=18.1 ~812m) was discovered at 1536 UT 09 June by the Siding Spring Survey (SSS), which observed it at June 9.65-68p4, 9.74-81p8, and 10.59p4. The discovery was confirmed by Jim Young via Table Mtn. Obs. (June 10.41-43p4) and Mt. John Obs. (June 10.58-59p3).
MPEC 2007-L40 - "09:34 UT" - 2007 LU
- K07L00U 2007 LU (small asteroid, Earth MOID=3.6 LD, H=23.4 ~71m) was discovered at 1438 UT 09 June by SSS, which observed it at June 9.61-64p4, 9.69-81p11, and 10.59p4. The discovery was confirmed by Mt. John Obs. (June 10.38p3 & 10.64-65p3) and Young/Table Mtn. (June 10.43-45p4).
MPEC 2007-L39 - "09:31 UT" - 2007 LT
- K07L00T 2007 LT (small asteroid, Earth MOID=2.3 LD, H=22.4 ~112m) was discovered at 0845 UT 09 June by the Catalina Sky Survey (CSS), which observed it at June 9.37-42p7. The discovery was confirmed by Naef Obs. (June 9.98-00p4), Eschenberg Obs. (June 10.03p6), Guidestar Obs. (June 10.04-05p3), Grasslands Obs. (June 10.32p3), Astronomical Research Obs. (ARO) (June 10.32-33p7), Young/Table Mtn. (June 10.32-34p4), and Mt. John Obs. (June 10.51p3).
MPEC 2007-L38 - "09:29 UT" - 2007 LS
- K07L00S 2007 LS (risk-listed, Q=4.394 AU, H=17.7 ~977m) was discovered at 0659 UT 08 June by the Spacewatch 0.9m telescope, which observed it at June 8.29-33p3. The discovery was confirmed by KLENOT (June 8.97-98p2), ARO (June 9.15-16p3), Farpoint Obs. (June 9.20-21p2), the Spacewatch 1.8m telescope (June 9.22-23p3 & 11.26-27p3), and Mt. John Obs. (June 10.46-47p3).
- Observations of small asteroids (H>22.0)
- K07K02W 2007 KW2 (arc=20 days, H=22.3 ~117m) from Desert Moon Obs. (June 10.31-34p3)
- K06S05Y 2006 SY5 (arc=2 opp, H=22.1 ~129m) from Mt. John Obs. (June 10.66-67p3)
- K06F36H 2006 FH36 (arc=2 opp, H=22.9 ~89m) from Mt. John Obs. (June 10.60-63p4)
- Observations of almost-small asteroids (21.7<H<=22.0)
- K04K01E 2004 KE1 (arc=2 opp, H=21.8 ~148m) from Mt. John Obs. (June 10.54-57p3)
- Observations of other objects
- K07L00L 2007 LL (arc=3 days, H=19.7 ~389m) from Balzaretto Obs. (June 9.89-91p2), Stonegate Obs. (June 10.10-11p6), Mt. John Obs. (June 10.36p3), and Great Shefford Obs. (June 10.96p3)
- K07L00F 2007 LF (arc=4 days, H=20.6 ~257m) from Balzaretto Obs. (June 9.93-94p4), Hamamatsu-Yuto Obs. (June 10.56-57p8), Great Shefford Obs. (June 10.97p3), and Dark Roseanne Obs. (June 11.06-07p4)
- K07L00E 2007 LE (arc=4 days, H=19.2 ~490m) from CSS (June 10.20-22p4) and Great Shefford Obs. (June 10.91-92p3)
- K07L00D 2007 LD (arc=4 days, H=19.0 ~537m) from Young/Table Mtn. (June 10.19-21p4) and Great Shefford Obs. (June 10.95p3)
- K07L00A 2007 LA (arc=5 days, H=21.5 ~170m) from Young/Table Mtn. (June 10.23-24p4) and Great Shefford Obs. (June 10.92-93p3)
- K07J22F 2007 JF22 (Q=4.916 AU, arc=29 days, H=16.2 ~1.95 km) from Desert Moon Obs. (June 10.19-20p3)
- K07J02X 2007 JX2 (arc=32 days, H=19.4 ~446m) from Spacewatch 1.8m (June 10.26-27p3)
- K07H15E 2007 HE15 (arc=49 days, H=19.7 ~389m) from Mt. John Obs. (June 10.31-33p3)
- K07F42V 2007 FV42 (arc=82 days, H=17.9 ~891m) from Iluro Obs. (June 10.09p3)
- K07F01L 2007 FL1 (arc=85 days, H=18.7 ~616m) from SSS (June 10.65-69p4)
- K07D08F 2007 DF8 (arc=109 days, H=20.3 ~295m) from Santa Mama Obs. (June 9.86-87p2)
- K07B02T 2007 BT2 (arc=2 opp, H=17.2 ~1.23 km) from El Leoncito Obs. (June 3.09-13p4 & 4.11-12p3)
- K06W03L 2006 WL3 (arc=203 days, H=19.9 ~355m) from Desert Moon Obs. (June 10.26p2)
- K06V02V 2006 VV2 (arc=2 opp, H=16.8 ~1.48 km) from El Leoncito Obs. (June 2.02-05p4)
- K06G00B 2006 GB (arc=2 opp, H=20.3 ~295m) from CSS (June 10.33-35p4)
- K05W55S 2005 WS55 (arc=3 opp, H=16.1 ~2.04 km, q=1.110 AU) from Desert Moon Obs. (June 10.38p1)
- K05A13D 2005 AD13 (arc=2 opp, H=17.9 ~891m) from Santa Mama Obs. (June 9.88-89p3)
- K02S00Q 2002 SQ (arc=3 opp, H=19.5 ~426m) from ARO (June 10.36-38p2 at V=22.5-6)
- K02R25T 2002 RT25 (arc=3 opp, H=18.7 ~616m) from ARO (June 10.27-31p2 at V=22.9-23.1)
- K02K04F 2002 KF4 (i=37.2°, Q=4.571 AU, arc=3 opp, H=17.2 ~1.23 km) from Santa Mama Obs. (June 8.84-88p4, 9.83-85p2 & 9.90p1) and Hamamatsu-Yuto Obs. (June 10.58-59p6)
- K02C46Z 2002 CZ46 (arc=4 opp, H=17.9 ~891m) from ARO (June 10.18-19p4)
- K02A03Q 2002 AQ3 (i=40.0°, arc=4 opp, H=17.1 ~1.29 km) from CSS (June 10.39-42p4)
- K01Q96C 2001 QC96 (arc=3 opp, H=20.7 ~245m) from ARO (June 10.21-24p3 at V=22.8-23.0)
- F4007 154007 2002 BY from El Leoncito Obs. (June 2.98-00p4) and CSS (June 10.18-20p4)
- D6874 136874 1998 FH74 from Dark Roseanne Obs. (June 11.13-14p3)
- D6818 136818 1997 MW1 from Naef Obs. (June 9.99-01p2)
- A8519 108519 2001 LF from El Leoncito Obs. (June 3.02-03p3)
- 39796 39796 1997 TD from CSS (June 10.26-28p4)
- 07977 7977 1977 QQ5 from CSS (June 10.44-45p4)
- 03352 3352 McAuliffe (1981 CW) from El Leoncito Obs. (June 3.13-15p3)
Observers on 11 June '07
A total of 22 observing facilities appeared in this day's MPECs.
|H55||Astronomical Research Obs. in Illinois, 6 in MPECs 2007-L37, 2007-L38 & 2007-L39 -- 2007 LT, 2007 LS, 2002 SQ, 2002 RT25, 2002 CZ46, 2001 QC96|
|A81||Balzaretto Obs. in Italy, 2 in MPEC 2007-L37 -- 2007 LL, 2007 LF|
|703||Catalina Sky Survey in Arizona, 7 in MPECs 2007-L37 & 2007-L39 -- 2007 LT, 2007 LE, 2006 GB, 2002 AQ3, 154007, 39796, 7977|
|H98||Dark Roseanne Obs. in Connecticut, 2 in MPEC 2007-L37 -- 2007 LF, 136874|
|448||Desert Moon Obs. in New Mexico, 4 in MPEC 2007-L37 -- 2007 KW2, 2007 JF22, 2006 WL3, 2005 WS55|
|808||El Leoncito Obs. in Argentina, 5 in MPEC 2007-L37 -- 2007 BT2, 2006 VV2, 154007, 108519, 3352|
|151||Eschenberg Obs. in Switzerland, 1 in MPEC 2007-L39 -- 2007 LT|
|734||Farpoint Obs. in Kansas, 1 in MPEC 2007-L38 -- 2007 LS|
|651||Grasslands Obs. in Arizona, 1 in MPEC 2007-L39 -- 2007 LT|
|J95||Great Shefford Obs. in England, 5 in MPEC 2007-L37 -- 2007 LL, 2007 LF, 2007 LE, 2007 LD, 2007 LA|
|A17||Guidestar Obs. in Germany, 1 in MPEC 2007-L39 -- 2007 LT|
|379||Hamamatsu-Yuto Obs. in Japan, 2 in MPEC 2007-L37 -- 2007 LF, 2002 KF4|
|B19||Iluro Obs. in Spain, 1 in MPEC 2007-L37 -- 2007 FV42|
|246||KLENOT in the Czech Republic, 1 in MPEC 2007-L38 -- 2007 LS|
|474||Mt. John Obs. in New Zealand, 11 in MPECs 2007-L37, 2007-L38, 2007-L39, 2007-L40, 2007-L41, 2007-L42 & 2007-L43 -- 2004 VS60, C/2007 K6, 2007 LV, 2007 LU, 2007 LT, 2007 LS, 2006 SY5, 2006 FH36, 2004 KE1, 2007 LL, 2007 HE15|
|A13||Naef Obs. in Switzerland, 2 in MPECs 2007-L37 & 2007-L39 -- 2007 LT, 136818|
|B38||Santa Mama Obs. in Italy, 3 in MPEC 2007-L37 -- 2007 DF8, 2005 AD13, 2002 KF4|
|E12||Siding Spring Survey in New South Wales, 3 in MPECs 2007-L37, 2007-L40 & 2007-L41 -- 2007 LV, 2007 LU, 2007 FL1|
|691||Spacewatch 0.9m telescope in Arizona, 1 in MPEC 2007-L38 -- 2007 LS|
|291||Spacewatch 1.8m telescope in Arizona, 2 in MPECs 2007-L37 & 2007-L38 -- 2007 LS, 2007 JX2|
|H67||Stonegate Obs. in Michigan, 1 in MPEC 2007-L37 -- 2007 LL|
|6735||Jim Young via Table Mtn. Obs. in southern California, 5 in MPECs 2007-L37, 2007-L39, 2007-L40 & 2007-L41 -- 2007 LV, 2007 LU, 2007 LT, 2007 LD, 2007 LA|
Impact Risk Monitoring on 11 June '07
Notes for Today's Latest Risk Assessments
|2007 LS||JPL||1430||2050-2098||9||2.1e-09||-5.59||-6.29||0||JPL: "Analysis based on 19 observations spanning 2.9739 days (2007-Jun-08.29124 to 2007-Jun-11.26518)." Diameter approximately 0.791 km. from mean, weighted H=18.2.|
For a list of all risk-rated objects recently in view, see our ephemerides page.
An impact solution, also known as a "virtual impactor" (VI), is not a prediction but rather a possibility derived from an orbit calculation that cannot be eliminated yet based on the existing data. Elimination can come quickly with just a little further observation or may take weeks or months, sometimes years. Once superceded or eliminated, a former impact solution has zero relevance to an object's risk. See Jon Giorgini's "Understanding Risk Pages" for more about all this.
Chronology on 11 June '07
Times are UTC for when the items were noted by Major News.
|2233||Added link to news story, "Was blinding light a meteor?"|
Added link to news story, "Geologists to name 'new' meteorite crater after Havre couple"
|1951||Added news report, "Scientific papers"|
Added news report, "Site schedule note"
|1557||Grabbed MPEC 2007-L43 - 2004 VS60 - see above|
Grabbed MPEC 2007-L44 - 2007 JF22 = 2007 AL - see above
|1514||Grabbed MPEC 2007-L42 - Comet C/2007 K6 (McNaught) - see above|
|1430||Noted that JPL has posted 2007 LS as an impact risk - see above|
Grabbed MPEC 2007-L37 - Daily Orbit Update - see above
Grabbed MPEC 2007-L39 - 2007 LT - see above
Grabbed MPEC 2007-L41 - 2007 LV - see above
|1429||Grabbed MPEC 2007-L38 - 2007 LS - see above|
Grabbed MPEC 2007-L40 - 2007 LU - see above
|0532||Added MOS paper, "Co-orbital Oligarchy" - see above|
Added MOS paper, "Evolution of interstellar dust and stardust in the solar neighbourhood" - see above
Added MOS paper, "From mean-motion resonances to scattered planets: Producing the Solar System, eccentric exoplanets and Late Heavy Bombardments" - see above
Added MOS paper, "Physical Investigation of the Potentially Hazardous Asteroid (144898) 2004 VD17" - see above
Added news report, "Meteorite books"