<<   Top | Contents | News | Science | NEOCP | MPECs | Observers | Risks | Chronology | Index   >>

Unfocussed micrometeor trail caught in a Subaru 8.2-meter telescope exposure. See links to more info and images below. Copyright: Subaru Telescope.

Contents  on 11 September '07

• Minor-Object News -- seven items
• Minor-Object Science -- eight papers
• IAU Minor Planet Center
  • NEOCP Activity -- nine listings: 8 new, 1 updated
  • New MPECs -- twelve MPECs
  • Observers -- 21 observing facilities
• Impact Risk Monitoring -- four objects reported
• Chronology

Resources:

• Consolidated Risk Tables - CRT page
• Ephemerides for risk-rated objects
• Ephemerides for small asteroids

The latest news: framed access (best), RSS news feed (flags updates), or redirection - Note: A/CC has a main Web site and a backup site.

Navigation tips: Use the << and >> arrows on the menus for each regular section (Observers, Risks, etc.) to move to the previous and next day's news for that section. Use the Index menu item to access specific days this year through a calendar interface. And use the all-up news archive to access news from any time since A/CC began in early 2002. To keep track of what's new each day, watch the Chronology section.

<<   Top | Contents | News | Science | NEOCP | MPECs | Observers | Risks | Chronology | Index   >>

Minor-Object News  on 11 September '07

• "Subaru Astronomers Measure Meteoroid Tunnels in Earth's Atmosphere," Subaru Telescope 10 Sept. - Quote: "The actual size of meteoroids studied in the current observation was estimated to be between 0.1 and 1 millimeters (derived from their luminosity)... The [research] team compared the number of special photons produced as a meteoroid collided with the atmospheric atoms and found a typical column width as narrow as a few millimeters across. This is the first time the width of a meteor track column has been precisely measured using a physical analysis of the light emitted during the event." - Note: The news release comments that "By focusing the Subaru Telescope to the altitude of meteors, one can make highly sensitive imaging observation of faint meteors and further study the population of micro-meteoroids." The results reported here, however, come from studying unfocussed trails accidentally captured while the 8.2-meter telescope was observing at infinity. See an A/CC-processed image above from the news release. {permalink}
  • "'Shooting Star' Trails Narrower Than A Pencil Lead," Space.com 11 Sept. - Quote: "The trails were estimated to be narrower than a meter... Turns out they are amazingly thin compared to the light show they create." {permalink}
• Lunar impacts: NASA Marshall's Meteoroid Environment Office has posted the first entries to its Lunar Impacts page since May. Four impacts by "sporadic" meteors (not associated with any showers) are reported from 8, 9, and 21 August. More details are reported in a 144Kb PDF. {permalink}
• "Occultation by (146) Lucina on Sept. 20," David Dunham 10 Sept. - Quote: "Observers across most of the western and central USA, northern Mexico, and Canada west of Quebec have a chance to make confirmatory observations of [Lucina's probable] satellite if they monitor the easily-found 7.9-mag. star SAO 78252 [on Thursday morning Sept. 20th]... In addition, observers ... will have a spectacular occultation by Lucina that will last almost 7 seconds." - Note: Included is a list of locations in the path, including a number of MPC-coded observatories. {permalink}
  • "Occultation by the large asteroid (704) Interamnia," David Dunham 10 Sept. - Note: First preliminary report of observations by at least seven stations on the morning of September 9th in Iowa, Michigan, and New Mexico. {permalink}
• Distant EKOs: The bimonthly September issue of Distant EKOs has been posted with abstracts of science papers related to Kuiper Belt and other distant minor objects, including several about surface compositions and one on the Oort Cloud. Some of these listings include links to PDF preprints. {permalink}
• "Life's Ingredients May Have 'Sprinkled' on Earth," Space.com 11 Sept. - Quote: "A new computer model indicates clouds of adenine molecules, a basic component of DNA, can form and survive the harsh conditions of space, and possibly sprinkle onto planets as the stars they orbit travel through a galaxy... Adenine is one of four 'letters' of DNA's alphabet used to store an organism's genetic code." {permalink}

<<   Top | Contents | News | Science | NEOCP | MPECs | Observers | Risks | Chronology | Index   >>

Minor-Object Science  on 11 September '07

• "Occultation observation to probe the turbulence scale size in the plasma tail of comet Schwassmann-Wachmann 3-B" by Roy, Nirupam with P.K. Manoharan & Pavan Chakraborty, abstract & PDF at arXiv.org 11 Sept. - Quote: "We present the occultation observation of compact radio source B0019-000 through the plasma tail of comet Schwassmann-Wachmann 3-B. The observation was made with the Ooty Radio Telescope at 326.5 MHz on May 26, 2006 when the plasma tail of the comet was in front of this source. The scintillation was found to be increased significantly for the target source compared to that of a control source. The intensity fluctuation power spectra show both steepening at high spatial scales and excess power at low spatial scales. This observation can be attributed to the turbulence in the comet plasma tail. A two-regime plasma turbulence can explain the time-evolution of the power spectrum during the occultation observation." {permalink}
• "The Relativistic Factor in the Orbital Dynamics of Point Masses" by Benitez, Federico with Tabare Gallardo, abstract & PDF at arXiv.org 11 Sept. - Quote: "There is a growing population of relativistically relevant minor bodies in the Solar System and a growing population of massive extrasolar planets with orbits very close to the central star where relativistic effects should have some signature. Our purpose is to review how general relativity affects the orbital dynamics of the planetary systems and to define a suitable relativistic correction for Solar System orbital studies when only point masses are considered... Relativistic effects generated by the Sun or by the central star are the most relevant ones and produce evident modifications in the secular dynamics of the inner Solar System... Relativistic effects generated by planets instead are of very low relevance but detectable in numerical simulations." - Note: This paper says "there are at present around half hundred asteroids" with greater relativistic effects on their orbits than the classic example of 1566 Icarus. A table of 15 is given and two others are mentioned, especially 2003 CP20 and also 2000 LK, which get their own figures along with 2004 XY60. Furthermore, it concludes that "Relativistic corrections should also be applied to comets," a problem complicated by non-gravitational forces (outgassing). {permalink}
• "Light-induced disassembly of dusty bodies in inner protoplanetary discs: implications for the formation of planets" by Wurm, Gerhard, abstract & PDF at arXiv.org 11 Sept. - Quote: "Applied to protoplanetary discs, dusty bodies smaller than several kilometres in size which are closer to a star than about 0.4 au are subject to a rapid and complete disassembly to submillimetre size dust aggregates... While an inward-drifting dusty body is destroyed, the generated dust is not lost for the disc by sublimation or subsequent accretion on to the star but can be reprocessed by photophoresis or radiation pressure." {permalink}
• "Magnetic fields and accretion flows on the classical T Tauri star V2129 Oph" by Donati, J.F. with M.M. Jardine, S.G. Gregory & 8 others, abstract & PDF at arXiv.org 11 Sept. - Quote: "[What we find] suggests that the stellar magnetic field succeeds in coupling to the accretion disc as far out as the corotation radius, and could possibly explain the slow rotation of V2129 Oph." {permalink}
• "Toward a Deterministic Model of Planetary Formation IV: Effects of Type-I Migration" by Ida, Shigeru with D.N.C. Lin, abstract & PDF at arXiv.org 11 Sept. - Quote: "During the early embedded phase of protostellar disks, although embryos rapidly emerge in regions interior to the ice line, uninhibited type-I migration leads to their efficient self-clearing. But, embryos continue to form from residual planetesimals at increasingly large radii, repeatedly migrate inward, and provide a main channel of heavy element accretion onto their host stars. During the advanced stages of disk evolution (a few Myr), the gas surface density declines to values comparable to or smaller than that of the minimum mass nebula model and type-I migration is no longer an effective disruption mechanism for mars-mass embryos." {permalink}
• "The Formation of Fragments at Corotation in Isothermal Protoplanetary Disks" by Durisen, Richard H. with Thomas W. Hartquist & Megan K. Pickett, abstract & PDF at arXiv.org 11 Sept. - Quote: "In this paper, we offer analytic arguments for why, at low Q [Toomre stability parameter], fragments are most likely to form first at the corotation radii of growing spiral modes, and we support these arguments with results from 3D hydrodynamics simulations." {permalink}
• "Oligarchic planetesimal accretion and giant planet formation" by Fortier, A. with O.G. Benvenuto & A. Brunini, abstract & PDF at arXiv.org 11 Sept. - Quote: "With regard to the size of accreted planetesimals, we find that for a swarm of planetesimals having a radius of 10 km, the formation time is a factor 2 to 3 shorter than that of planetesimals of 100 km, the factor depending on the surface density of the nebula. Moreover, planetesimal size does not seem to have a significant impact on the final mass of the [gas giant solid] core." {permalink}
• "The Nature of the Dense Core Population in the Pipe Nebula: Thermal Cores Under Pressure" by Lada, Charles J. with August A. Muench, Jill M. Rathborne & 2 others, abstract & PDF at arXiv.org 11 Sept. - Quote: "In this paper we present the results of a systematic investigation of an entire population of starless dust cores within a single molecular cloud... Most of the cores appear to be pressure confined, gravitationally unbound entities whose nature, structure and future evolution are determined by only a few physical factors which include self-gravity, the fundamental processes of thermal physics and the simple requirement of pressure equilibrium with the surrounding environment. The observed core properties likely constitute the initial conditions for star formation in dense gas." {permalink}

<<   Top | Contents | News | Science | NEOCP | MPECs | Observers | Risks | Chronology | Index   >>

NEOCP Activity  on 11 September '07

The MPC's NEO Confirmation Page has 9 listings: 8 new, 1 updated

When last checked at 2354 UTC today, the Minor Planet Center's NEO discovery Confirmation Page (NEOCP) had eight new and one updated listings. Of these, eight were "one nighters." So far Major News has counted a total of 22 objects listed on the NEOCP at some point today.

To learn how observers use the NEOCP, see the Practical guide on how to observe NEOCP object by Birtwhistle et al. at Suno Observatory.

<<   Top | Contents | News | Science | NEOCP | MPECs | Observers | Risks | Chronology | Index   >>

New MPECs  on 11 September '07

Minor Planet Electronic Circulars

As of last check at 2354 UTC, there have been twelve MPECs issued today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

• MPEC 2007-R42 time-stamped "06:08 UT" - Daily Orbit Update - see below
• MPEC 2007-R43 time-stamped "10:36 UT" - 2002 RT129 - see below
• MPEC 2007-R44 time-stamped "10:40 UT" - 2000 SY162 - see below
• MPEC 2007-R45 time-stamped "15:26 UT" - 1998 QB28 - see below
• MPEC 2007-R46 time-stamped "15:49 UT" - 2007 RP9 - see below
• MPEC 2007-R47 time-stamped "15:56 UT" - 2007 RR9 - see below
• MPEC 2007-R48 time-stamped "15:59 UT" - 2007 RS9 - see below
• MPEC 2007-R49 time-stamped "16:02 UT" - 2007 RT9 - see below
• MPEC 2007-R50 time-stamped "16:05 UT" - 2007 RU9 - see below
• MPEC 2007-R51 time-stamped "16:07 UT" - 2007 RV9 - see below
• MPEC 2007-R52 time-stamped "19:48 UT" - 2007 RY9 - see below
• MPEC 2007-R53 time-stamped "23:09 UT" - 2007 RU10

MPEC 2007-R53 - "23:09 UT" - 2007 RU10

• K07R10U   2007 RU10 (H=19.0 ~537m) was discovered at 0551 UT 11 Sept. by the Catalina Sky Survey (CSS), which observed it at Sept. 11.24-31p8 and 11.38p4. The discovery was confirmed by Eschenberg Obs. (Sept. 11.82-83p5) and Remanzacco Obs. (Sept. 11.89-90p3).

MPEC 2007-R52 - "19:48 UT" - 2007 RY9

• K07R09Y   2007 RY9 (small asteroid, H=23.2 ~78m) was discovered at 0555 UT 11 Sept. by CSS, which observed it at Sept. 11.25-31p8 and 11.38p4. The discovery was confirmed by Eschenberg Obs. (Sept. 11.81p3).

MPEC 2007-R51 - "16:07 UT" - 2007 RV9

• K07R09V   2007 RV9 (Earth MOID=1.8 LD, H=20.0 ~339m) was discovered at 0654 UT 10 Sept. by the Mt. Lemmon Survey (MLS), which observed it at Sept. 10.29-31p4 and 10.36-38p4. The discovery was confirmed by the Spacewatch 1.8m telescope (Sept. 11.27-28p3).

MPEC 2007-R50 - "16:05 UT" - 2007 RU9

• K07R09U   2007 RU9 (risk-listed, Earth MOID=0.2 LD, H=20.7 ~245m) was discovered at 0651 UT 10 Sept. by MLS, which observed it at Sept. 10.29-31p4, 10.36-37p4, and 11.27-30p4. The discovery was confirmed by Great Shefford Obs. (Sept. 11.10-11p3), Jim Young via Table Mtn. Obs. (Sept. 11.30-32p4), and Grasslands Obs. (Sept. 11.40-41p3).

MPEC 2007-R49 - "16:02 UT" - 2007 RT9

• K07R09T   2007 RT9 (H=19.0 ~537m) was discovered at 0649 UT 10 Sept. by MLS, which observed it at Sept. 10.28-31p4 at V=22.1-4, 10.36-37p4 at V=22.1-2, and 11.28-30p4 at V=22.4. The discovery was confirmed by Spacewatch 1.8m (Sept. 11.28-32p3).

MPEC 2007-R48 - "15:59 UT" - 2007 RS9

• K07R09S   2007 RS9 (small asteroid, H=24.9 ~35m) was discovered at 0612 UT 10 Sept. by MLS, which observed it at Sept. 10.26-32p8 and 11.28-30p4.

MPEC 2007-R47 - "15:56 UT" - 2007 RR9

• K07R09R   2007 RR9 (risk-listed, Q=4.830 AU, H=20.3 ~295m) was discovered at 0505 UT 10 Sept. by CSS, which observed it at Sept. 10.21-24p4 and 10.30-33p4. The discovery was confirmed by Mataro Obs. (Sept. 10.87-88p3), Great Shefford Obs. (Sept. 10.89-91p4), CEAMIG-REA (Sept. 11.07-08p3), MLS (Sept. 11.25-30p8), Young/Table Mtn. (Sept. 11.26-27p4), and Grasslands Obs. (Sept. 11.43-44p3).

MPEC 2007-R46 - "15:49 UT" - 2007 RP9

• K07R09P   2007 RP9 (small asteroid, H=23.2 ~78m) was discovered at 0340 UT 10 Sept. by CSS, which observed it at Sept. 10.15-17p3, 10.21-24p4, and 10.30-32p3. The discovery was confirmed by Great Shefford Obs. (Sept. 10.89-90p3), Young/Table Mtn. (Sept. 11.20-22p4), MLS (Sept. 11.30-32p8 & 11.39-41p3), and Grasslands Obs. (Sept. 11.39-40p3).

MPEC 2007-R45 - "15:26 UT" - 1998 QB28

• J98Q28B   1998 QB28 (H=20.3 ~295m) from MLS (Sept. 10.38-41p4, 10.45-47p3 & 11.36-38p4) and Great Shefford Obs. (Sept. 11.07-09p2 & 11.13p1)

MPEC 2007-R44 - "10:40 UT" - 2000 SY162

• K00SG2Y   2000 SY162 (H=19.2 ~490m) from Young/Table Mtn. (Sept. 10.35-37p4 & 11.40-42p4)

MPEC 2007-R43 - "10:36 UT" - 2002 RT129

• K02RC9T   2002 RT129 (H=19.5 ~426m) from Young/Table Mtn. (Sept. 10.39-41p4 & 11.33-35p4)

<< DOU on 11 Sept. '07 >>  MPEC 2007-R42 - "06:08 UT" - Daily Orbit Update

• Observations of risk-listed objects
• K07R09A   2007 RA9 (arc=1 day, H=19.9 ~355m) from the Siding Spring Survey (SSS) (Sept. 10.67-68p7)
• K07R02F   2007 RF2 (arc=5 days, H=20.5 ~269m) from Spacewatch 1.8m (Sept. 10.43-44p3)
• Observations of recently (no longer) risk-listed objects
• K07R01J   2007 RJ1 (small asteroid, arc=7 days, H=25.1 ~32m) from Astronomical Research Obs. (ARO) (Sept. 10.10-12p3) and CSS (Sept. 10.16-17p4)
• K07P27V   2007 PV27 (arc=27 days, H=20.2 ~309m) from ARO (Sept. 10.08-09p4)
• Observations of small asteroids (H>22.0)
• K07R01O   2007 RO1 (arc=6 days, H=23.6 ~65m) from ARO (Sept. 10.12-13p6)
• K06BE7Z   2006 BZ147 (arc=3 opp, H=25.4 ~28m) from Spacewatch 1.8m (Sept. 10.39p3)
• Observations of other objects
• K07R01T   2007 RT1 (arc=6 days, H=20.6 ~257m) from ARO (Sept. 10.20-21p4) and CSS (Sept. 10.25-26p3)
• K07R01D   2007 RD1 (arc=8 days, H=21.6 ~162m) from ARO (Sept. 10.12-13p5)
• K07Q02K   2007 QK2 (arc=19 days, H=20.6 ~257m) from Stia Obs. (Sept. 9.82-84p4)
• K07P11U   2007 PU11 (Q=4.384 AU, arc=3 opp, H=16.3 ~1.86 km) from New Millennium Obs. (Sept. 8.07-12p6)
• K07P08E   2007 PE8 (arc=117 days, H=19.4 ~446m) from Ca del Monte Obs. (Sept. 8.93-97p2)
• K07N05C   2007 NC5 (q=0.278 AU, Q=4.617 AU, arc=68 days, H=18.0 ~851m) from ARO (Sept. 10.10-11p4)
• K07L00L   2007 LL (arc=94 days, H=20.4 ~282m) from ARO (Sept. 10.05p1)
• K07K04N   2007 KN4 (Q=5.446 AU, arc=3 opp, H=17.0 ~1.35 km) from CSS (Sept. 5.45-47p4)
• K07F42V   2007 FV42 (arc=166 days, H=17.9 ~891m) from North Ryde Obs. (Sept. 2.53-56p2)
• K07F01E   2007 FE1 (arc=172 days, H=18.8 ~589m) from SSS (Sept. 5.55-57p4)
• K07DA3T   2007 DT103 (arc=2 opp, H=19.2 ~490m) from LONEOS (Sept. 9.31-38p4) and Atlante Obs. (Sept. 9.97-99p3)
• K07D41L   2007 DL41 (arc=2 opp, H=20.6 ~257m) from Spacewatch 1.8m (Sept. 10.45p2)
• K07D08K   2007 DK8 (arc=201 days, H=19.0 ~537m) from SSS (Sept. 6.62-64p4)
• K07C26K   2007 CK26 (arc=2 opp, H=19.0 ~537m) from SSS (Sept. 6.46-49p3)
• K06C00X   2006 CX (arc=2 opp, H=19.0 ~537m) from Spacewatch 1.8m (Sept. 10.35-36p3)
• K04W02S   2004 WS2 (arc=4 opp, H=18.0 ~851m) from Spacewatch 1.8m (Sept. 10.48-49p3 at V=22.3-4)
• K04T13R   2004 TR13 (arc=3 opp, H=18.5 ~676m) from CSS (Sept. 8.48-49p4)
• K04T01P   2004 TP1 (arc=2 opp, H=20.7 ~245m) from Spacewatch 1.8m (Sept. 10.49-51p2)
• K04R09N   2004 RN9 (arc=3 opp, H=20.8 ~234m) from CSS (Sept. 10.42-44p4)
• K02RC9N   2002 RN129 (arc=4 opp, H=18.9 ~562m) from CSS (Sept. 10.31-33p4)
• K02F05W   2002 FW5 (i=46.4°, arc=3 opp, H=19.2 ~490m) from Spacewatch 1.8m (Sept. 10.40-41p2)
• K01Q34C   2001 QC34 (arc=2 opp, H=20.0 ~339m) from CSS (Sept. 10.15-17p4)
• K00Y29F   2000 YF29 (arc=4 opp, H=20.4 ~282m) from Spacewatch 1.8m (Sept. 10.27-28p3)
• J99S05O   1999 SO5 (arc=2 opp, H=21.1 ~204m) from Spacewatch 1.8m (Sept. 10.46-47p3)
• J99J03U   1999 JU3 (arc=4 opp, H=19.3 ~467m) from Stia Obs. (Sept. 9.77-79p5) and CSS (Sept. 10.15-24p10 & 10.30-33p4)
• J99H02A   1999 HA2 (Q=4.740 AU, arc=2 opp, H=17.7 ~977m) from Spacewatch 1.8m (Sept. 10.37-38p3)
• F4330   154330 2002 VX94 from the Spacewatch 0.9m telescope (Sept. 10.21-25p3) and CSS (Sept. 10.22-24p4)
• E3678   143678 2003 SA224 from LINEAR (Sept. 7.35-38p3) and CSS (Sept. 10.38-41p4)
• 26166   26166 1995 QN3 from CSS (Sept. 5.29-31p4) and LONEOS (Sept. 8.33-37p3)
• 21374   21374 1997 WS22 from Atlante Obs. (Sept. 9.13-14p2)
• 16636   16636 1993 QP from San Benedetto Po Obs. (Sept. 7.80-81p4), Ca del Monte Obs. (Sept. 8.90-94p2), and Atlante Obs. (Sept. 8.93-96p2 & 9.01p1)
• 14402   14402 1991 DB from Spacewatch 0.9m (Sept. 10.28-32p3)
• 08034   8034 Akka (1992 LR) from CSS (Sept. 8.48-49p4)
• 07977   7977 1977 QQ5 from Atlante Obs. (Sept. 9.15p3)
• 06050   6050 Miwablock (1992 AE) from SSS (Sept. 6.42-43p2)
• 05879   5879 Almeria (1992 CH1) from MLS (Sept. 10.20-22p4)
• 05143   5143 Heracles (1991 VL) from CSS (Sept. 10.19-21p4)
• 04954   4954 Eric (1990 SQ) from SSS (Sept. 6.61-64p4)
• 04183   4183 Cuno (1959 LM) from CSS (Sept. 10.21-23p3 & 10.30-33p4)
• 03753   3753 Cruithne (1986 TO) from Ca del Monte Obs. (Sept. 9.14-15p2)
• 02212   2212 Hephaistos (1978 SB) from CSS (Sept. 10.41-44p4)
• 01865   1865 Cerberus (1971 UA) from LINEAR (Sept. 7.35-38p4)
• 01685   1685 Toro (1948 OA) from SSS (Sept. 6.42-43p2)
• 01221   1221 Amor (1932 EA1) from MLS (Sept. 10.33-34p3)

<<   Top | Contents | News | Science | NEOCP | MPECs | Observers | Risks | Chronology | Index   >>

Observers  on 11 September '07

A total of 21 observing facilities appear in today's MPECs.

<<   Top | Contents | News | Science | NEOCP | MPECs | Observers | Risks | Chronology | Index   >>

Impact Risk Monitoring  on 11 September '07

Legend: VI# = VI count, Prob Cum = cumulative probability, PS Cum/Max = cumulative/maximum Palermo Scale, TS = Torino Scale

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 this.

<<   Top | Contents | News | Science | NEOCP | MPECs | Observers | Risks | Chronology | Index   >>

Chronology  on 11 September '07

Times are UTC for when the items were noted or added by Major News.