31 July-6 Aug. '06 - A/CC Small Object Report

ACC's Small Object Report for 31 July - 6 August 2006

A semi-automated report compiled on 6 August 2006 at 2359 UTC

Five small asteroids were reported in the last 168 hours, during which none were newly discovered.

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Editor's note: As asteroids go, "small" is defined as having an absolute magnitude (brightness) calculated at greater than H=22.0, which converts very roughly to a diameter under 135 meters. No matter how close they come to the Earth, the astronomical community does not classify such objects as "potentially hazardous." However, as demonstrated by the mile wide (1.6 km.) Barringer Crater in Arizona, blasted out by a "small" asteroid some 50,000 years ago, there are asteroids too small to be labeled "potentially hazardous" that actually could cause severe local damage. These are sometimes called "Tunguska-class objects" (TCOs), after the 1908 event probably caused by a comet fragment or asteroid too small to be classified today as hazardous but packing enough wallop to flatten a Siberian forest area the size of a large city.
NEODyS in December 2005 changed its main Risk page to classify "Objects too small to result in heavy damage on the ground" as having "absolute magnitude > 25," which corresponds to perhaps 35 meters wide. And JPL two months earlier started flagging (with a blue background) risk-listed objects of "Estimated diameter 50 meters or less" as "not likely to cause significant damage in the event of an impact, although impact damage does depend heavily upon the specific (and usually unknown) physical properties of the object in question."
Small asteroids that come close enough to Earth to be seen have significant potential for scientific study today, and for exploration and exploitation in the future. They present a sampling of distant asteroid populations and a few may be remnants of the event that created the Earth-Moon system.
Some of these objects are discovered while close to Earth moving across the sky quite quickly, when they are called "FMOs" or "VFMOs" (very fast moving objects). The discovery and follow-up tracking of asteroids with H>22.0 represents some of the most difficult and very best observing work being done today by amateur and professional astronomers around the world, and the page you are reading is dedicated to recognizing their ongoing successes.

Object Listings -- smallest objects first [ Alpha Index | 48 Hours | top ]

Size estimate: 37 meters per JPL H=24.82, MPC H=24.8 JPL classifies 2006 OE10 as an Amor and calculates an Earth MOID of 0.047656 AU (18.54 LD), and reports this object passed Earth at 18.7 lunar distances (LD) on 23 July 2006. Observations are reported from the following observatories in MPECs 2006-P06 and 2006-P19: Great Shefford Obs. [J95] 2006-08-02 0110-0129, 4 pos. in MPEC 2006-P06, follow-up Siding Spring Survey (SSS) [E12] 2006-08-03 1729-1733, 2 pos. in MPEC 2006-P19, follow-up See also information from the week ending 30 July 2006. 2006 OB7 (K06O07B) [ JPL Orbit Viewer | NEODyS object home | news | viewing | index | top ]

Size estimate: 55 meters per JPL H=23.93, MPC H=24.0 JPL classifies 2006 OB7 as an Amor and calculates an Earth MOID of 0.031055 AU (12.08 LD), and reports this object passed Earth at 13.3 LD on 25 July 2006. Observations are reported from the following observatories in MPEC 2006-P07: Powell Obs. [649] 2006-08-02 0742-0811, 4 pos. in MPEC 2006-P07, follow-up See also information from the week ending 30 July 2006. 2006 OY4 (K06O04Y) [ JPL Orbit Viewer | NEODyS object home | news | viewing | index | top ]

Size estimate: 65 meters per JPL H=23.57, MPC H=23.5 JPL classifies 2006 OY4 as an Amor and calculates an Earth MOID of 0.086402 AU (33.62 LD), and reports this object passed Earth at 34.8 LD on 30 July 2006. Lowell Observatory reports 2006 OY4 has an MOID of 0.04325 AU (16.83 LD) with Mars. Observations are reported from the following observatories in MPEC 2006-P19: Siding Spring Survey (SSS) [E12] 2006-08-03 1737-1741, 2 pos. in MPEC 2006-P19, follow-up See also information from the week ending 30 July 2006. 2006 OC7 (K06O07C) [ JPL Orbit Viewer | NEODyS object home | news | viewing | index | top ]

Size estimate: 96 meters per JPL H=22.74, MPC H=22.8 JPL classifies 2006 OC7 as an Amor and calculates an Earth MOID of 0.040448 AU (15.74 LD), and reports this object passed Earth at 18.3 LD on 19 July 2006. Observations are reported from the following observatories in MPEC 2006-O66: Naef Obs. [A13] 2006-07-30 2158-2211, 5 pos. in MPEC 2006-O66, follow-up See also information from the week ending 30 July 2006. 1999 LK1 (J99L01K) [ JPL Orbit Viewer | NEODyS object home | news | viewing | index | top ]

Size estimate: 129 meters per JPL H=22.09, MPC H=22.1 JPL classifies 1999 LK1 as an Aten and calculates an Earth MOID of 0.027513 AU (10.71 LD). Observations are reported from the following observatories in MPEC 2006-P08: Mauna Kea [568{2}] coded to David Tholen et al. 2006-07-20 0908-0924, 3 pos. in MPEC 2006-P08, follow-up 2006-07-26 0929-0934, 2 pos. in MPEC 2006-P08, follow-up

48+120 Hours [ Objects Listings (size order) | Object Index (alpha/xref) | top ]

Observations of five small objects were reported during the last 168 hours: 1999 LK1, 2006 OB7, 2006 OC7, 2006 OE10 & 2006 OY4 in MPECs: 2006-O66 time-stamped 2006 July 31, 06:09 UT - Daily Orbit Update 2006-P06 time-stamped 2006 Aug. 2, 06:07 UT - Daily Orbit Update 2006-P07 time-stamped 2006 Aug. 3, 06:09 UT - Daily Orbit Update 2006-P08 time-stamped 2006 Aug. 3, 14:51 UT - 1999 LK1 2006-P19 time-stamped 2006 Aug. 5, 06:09 UT - Daily Orbit Update Date & times for other sources that were parsed to compile this page: JPL Close Approaches, downloaded at 2006 Aug. 5, 1735 UTC JPL NEO Orbital Elements, downloaded at 2006 Aug. 5, 1751 UTC Lowell Observatory Orbit intersections, time-stamped 2006 Aug 06 1456:13 UTC MPC NEA.DAT from MPC mirror, downloaded at 2006 Aug. 5, 1733 UTC Risk monitoring sites, as of A/CC's check at 2006 Aug. 6, 2359 UTC (see CRT page) Some observation sets have MPEC codes in parentheses, such as (*) denoting discovery.

Viewing Opportunities for Small Objects [ news | size order | alpha order | top ]

This compilation shows 10 small objects as being currently in view, including 5 not reported in the last seven days. Viewing by date order - see this list also by designation order Object View until MOID AU Dia H Arc Notes (calc date) ---------- ---------- -------- --- ----- --- - ----------------------- 2006 OA1 2006-08-09 0.099911 119 22.27 7 - past obs. - (27 July) 2006 OB7 2006-08-26 0.031055 55 23.93 9 - (3 Aug.) 2006 MH10 2006-09-01 0.124765 122 22.22 23 - past obs. - (16 July) 2006 KK103 2006-09-01 0.139955 110 22.44 50 - past obs. - (16 July) 2006 OC7 2006-09-07 0.040448 96 22.74 7 - (31 July) 1999 LK1 2006-09-11 0.027513 129 22.09 2op - (3 Aug.) 54509 2006-09-15 0.000154 104 22.56 4op - aka 2000 PH5 - past obs. - (26 July) 2006 OE10 2006-09-15 0.047656 37 24.82 8 - (5 Aug.) 2006 OY4 2006-10-03 0.086402 65 23.57 5 - (27 July) 1998 HG49 2006-12-21 0.076404 141 21.91 3op - "only 1 night" - past obs. - (16 July) Coming into view soon: 2005 QQ87 2006-09-18 0.079408 95 22.76 10 - >10 Aug., faint recov. poss. - (16 July) 1999 RJ33 2006-10-10 0.026859 108 22.49 16 - >11 Aug., faint recov. poss. - (16 July) 2004 SC56 2006-10-19 0.011296 92 22.84 13 - >11 Aug., faint recov. poss. - (16 July) Viewing by designation order - see also Viewing by date order Object View until MOID AU Dia H Arc Notes (calc date) ---------- ---------- -------- --- ----- --- - ----------------------- 2006 OE10 2006-09-15 0.047656 37 24.82 8 - (5 Aug.) 2006 OC7 2006-09-07 0.040448 96 22.74 7 - (31 July) 2006 OB7 2006-08-26 0.031055 55 23.93 9 - (3 Aug.) 2006 OY4 2006-10-03 0.086402 65 23.57 5 - (27 July) 2006 OA1 2006-08-09 0.099911 119 22.27 7 - past obs. - (27 July) 2006 MH10 2006-09-01 0.124765 122 22.22 23 - past obs. - (16 July) 2006 KK103 2006-09-01 0.139955 110 22.44 50 - past obs. - (16 July) 2005 QQ87 2006-09-18 0.079408 95 22.76 10 - >10 Aug., faint recov. poss. - (16 July) 2004 SC56 2006-10-19 0.011296 92 22.84 13 - >11 Aug., faint recov. poss. - (16 July) 1999 RJ33 2006-10-10 0.026859 108 22.49 16 - >11 Aug., faint recov. poss. - (16 July) 1999 LK1 2006-09-11 0.027513 129 22.09 2op - (3 Aug.) 1998 HG49 2006-12-21 0.076404 141 21.91 3op - "only 1 night" - past obs. - (16 July) 54509 2006-09-15 0.000154 104 22.56 4op - aka 2000 PH5 - past obs. - (26 July) Out-of-view date based on MPES solar elongation <40° and/or magnitude V>22.0 at 1200 UT geocentric. (Not factored in is any lunar interference with viewing.) Objects are linked in the left-most column only if observed in the last seven days, while objects with earlier small-object reporting are linked under "Notes." Diameter ("Dia") is in meters, a very rough estimate from brightness (H). Observing "Arc" is from MPES in days or number of oppositions. "In view" does not necessarily mean locatable for objects with short arcs in prior years and for which a large search or accidental rediscovery are the best hopes.

Small object observation cross index [ size order | 48 Hours | viewing | top ]

Object

Observed by MPC code

568

649

A13

E12, J95