The Asteroid/Comet Connection's daily news journal about asteroids, comets, and meteors Today's issue status: done
Cover: From left to right, Pla D'Arguines and Begues observatories in southern Spain have been keeping an eye on 2004 HM, as seen seen at upper left early on the 19th and lower right late on the 21st. This small object with currently one impact solution (see below) has been flying near Earth since its discovery April 16th, three days after it came within 5.1 lunar distances. See also the April 19th cover with Pla D'Arguines confirmation images from the 18th. |
| Small objects – panel 1/2 | Major News for 25 April 2004 |
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Small objects From Monday through today, six newly discovered small asteroids were announced (two with impact solutions), ten more small ones were followed (one with impact solutions), and there were belated reports of follow-up observations for another four, plus results found in the archives for three more. The recent work involved 23 observing facilities. (By "small," we mean with absolute magnitude of H=22.0 or greater, which converts by a standard but inexact formula to 135 meters/yards wide or less.) According to the JPL Closest Approaches page, the closest flybys for this last week were 2004 GD, which came within 6.0 lunar distances (LD) on April 20th, 2004 HB at 10.2 LD on the 21st, and 2004 HC33 at 7.2 LD today. |
If an asteroid's orbit brings it to within 0.05 AU of Earth's orbit, it is categorized as "potentially hazardous" unless it has an absolute magnitude H greater than 22.0, which corresponds to a diameter on the order of 135
Notes: Diameters in the following observation summary table are rough best estimates from a standard but very inexact H-to-size formula using H (absolute magnitude) from the JPL NEO Orbital Elements page, source also for Earth MOID (minimum orbital intersection). Other planetary MOIDs are from Lowell Observatory. Current Minor Planet Center H is also given, along with the original H from each object's discovery MPEC. Priorities, visibilities, and campaigns are from the European Spaceguard Central Node (SCN). |
| Small objects – panel 2/2 (table) | Major News for 25 April 2004 |
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H = absolute magnitude (brightness), from which size is roughly estimated — m/yd = meters/yards — [cross index]
All objects had observations reported last week. Those on a light-blue background had observations from only before the week.
Object | Estimated diameter | JPL H | MPC H | Discovery H in MPEC |
Earth MOID | European Spaceguard Central Node priority/visibility/campaign |
|---|---|---|---|---|---|---|
| 2004 HE Apollo | 15 m/yd | 26.80 | 26.8 | 26.7 2004-H16 | 0.00004 AU | |
| 2004 HE was reported this last week as observed on 17 April by Mt. John Obs. This was the only observation of this Earth-Moon system intruder reported after its discovery announcement (see special report), adding six hours to what was originally a 1.173-day observing arc. It has an MOID of 0.027 AU with Mars. | ||||||
| 2004 HC33 Apollo | 23 m/yd | 25.85 | 25.9 | 25.8 2004-H60 | 0.01762 AU | |
| NEW: 2004 HC33 was discovered on 23 April by FMO Project online volunteer Robert Gagliano of Arizona with the Spacewatch 0.9m telescope (see report yesterday), was confirmed on 23 April with the Spacewatch 1.8m telescope and Great Shefford Obs., and on 24 April by Grasslands Obs., and was announced in MPEC 2004-H60 of 24 April. This object was also observed on 24 April by LINEAR and Tenagra II Obs., and on 25 April by Great Shefford Obs. | ||||||
| 2004 HH20 Amor | 35 m/yd | 24.90 | 24.9 | 24.7 2004-H51 | 0.03015 AU | |
| NEW: 2004 HH20 was discovered on 21 April by LINEAR, which confirmed it on 22 April along with Great Shefford Obs. It was announced in MPEC 2004-H51 of 23 April, and was also observed on 23 April by LINEAR and Mt. John Obs. and on 24 April by Great Shefford Obs. and Mt. John Obs. | ||||||
| 2004 HD Amor | 40 m/yd | 24.63 | 24.8 | 24.5 2004-H19 | 0.03049 AU | |
| 2004 HD was observed on 17 April by Wykrota Obs., on 18 April by Hunters Hill Obs., on 19 April by Tenagra II Obs., on 20 April by Hunters Hill Obs., on 21 and 22 April by LINEAR and Hunters Hill Obs., on 23 April by Mt. John Obs., and on 25 April by Consell Obs. | ||||||
| 2004 GD2 Apollo | 52 m/yd | 24.08 | 24.3 | 24.2 2004-G28 | 0.02000 AU | Useful, visibility ends 7 Jun. |
| 2004 GD2 was observed on 18 April by Hunters Hill Obs., on 19 and 24 April by Great Shefford Obs., and on 22 and 23 April by LINEAR. It has an MOID of 0.001 AU with Mars. | ||||||
| 2004 GC19 Apollo | 52 m/yd | 24.07 | 24.1 | 24.1 2004-H06 | 0.03503 AU | Urgent, visibility ends 28 Apr. |
| 2004 GC19 was observed on 18 April by KLENOT, on 19 April by Great Shefford Obs. and Tenagra II Obs., and on 20 and 22-24 April by Great Shefford Obs. | ||||||
| 2004 GZ14 Apollo | 53 m/yd | 24.01 | 23.9 | 24.0 2004-G44 | 0.02768 AU | Necessary, visibility ends 29 Apr. |
| 2004 GZ14 was observed on 18 April by KLENOT and on 19 April by Great Shefford Obs. | ||||||
| 2004 FH29 Apollo | 58 m/yd | 23.84 | 24.0 | 23.7 2004-F87 | 0.01528 AU | |
| 2004 FH29 was reported this last week as observed on 9 April with the Australian Natl. Univ. (ANU) Obs. 1.0m telescope. | ||||||
| 2004 GD Apollo | 62 m/yd | 23.68 | 23.7 | 23.8 2004-G17 | 0.00600 AU | |
| 2004 GD was observed on 15 and 16 April by Goodricke-Pigott Obs., on 18 April by KLENOT, on 19 April by Great Shefford Obs., and on 20 April by Sormano Obs. It has an MOID of 0.033 AU with Venus. | ||||||
| 2004 FB18 Amor | 63 m/yd | 23.65 | 24.0 | 23.5 2004-F76 | 0.05858 AU | Useful, visibility ends 15 Jun. |
| 2004 FB18 was reported this last week as observed on 13 April with the ANU 1.0m telescope. | ||||||
| 2002 CV11 Apollo | 63 m/yd | 23.64 | 23.9 2002-C45 | 0.03376 AU | ||
| 2002 CV11 was reported this last week as observed on 12 Feb. 2002 by NEAT/Palomar, within the existing observing arc. | ||||||
| 2004 HB Apollo | 65 m/yd | 23.60 | 23.9 | 23.3 2004-H17 | 0.02136 AU | |
| 2004 HB was reported this last week as observed on 18 April by Mt. John Obs. | ||||||
| 2002 VS85 Apollo | 66 m/yd | 23.54 | 24.1 | 24.3 2002-V60 | 0.03124 AU | |
| 2002 VS85 was reported this last week as observed on 15 Nov. 2002 by NEAT/Palomar, adding six positions and 0.909 day to what had been a 2.165-day arc with 30 observations. | ||||||
| 2004 HT38 Amor | 71 m/yd | 23.40 | 23.6 | 23.6 2004-H71 | 0.09854 AU | |
| NEW: 2004 HT38 was discovered on 24 April by LINEAR, was confirmed on 24 April by Consell Obs., and on 25 April by Great Shefford Obs., Sabino Canyon Obs., Desert Moon Obs., and Mt. John Obs., and was announced in MPEC 2004-H71 of 25 April. It hasn't been reported since. | ||||||
| 2004 HQ1 Apollo has impact solutions | 77 m/yd | 23.23 | 23.1 | 23.0 2004-H38 | 0.00230 AU | |
| NEW: 2004 HQ1 was discovered on 19 April by LINEAR, was confirmed on 19 April by Great Shefford Obs., and on 20 April by LINEAR, and was announced in MPEC 2004-H38 of 20 April. This object was also observed on 22 April by KLENOT, on 24 April by Consell Obs., and on 21-23 by Great Shefford Obs. | ||||||
| 2004 HM Apollo has impact solution | 86 m/yd | 22.98 | 23.2 | 23.3 2004-H25 | 0.00338 AU | |
| 2004 HM was observed on 18 April by Wykrota Obs., on 19 April by Pla D'Arguines Obs. and Great Shefford Obs., on 20 April by Sormano Obs., on 21 April by Sandlot Obs. and Begues Obs., on 22 April by KLENOT and the Catalina Sky Survey (CSS), on 23 April by Great Shefford Obs., on 24 April by Begues Obs., and on 25 April by Begues Obs. and Consell Obs. See A/CC news edition "cover" images above and April 19th. | ||||||
| 2004 FP4 Amor | 89 m/yd | 22.90 | 23.3 | 23.3 2004-F47 | 0.05284 AU | Useful, visibility ends 22 Jul. |
| 2004 FP4 was observed on 13 April with the ANU 1.0m telescope, and on 21-23 April by LINEAR. It has an MOID of 0.009 AU with Mars. | ||||||
| 2004 GB19 Apollo | 90 m/yd | 22.87 | 23.0 | 22.7 2004-H04 | 0.01060 AU | Necessary, visibility ends 25 May |
| 2004 GB19 was observed on 18 April by Hunters Hill Obs., on 19 April by Great Shefford Obs. and Tenagra II Obs., on 20 April by Jornada Obs. and Sormano Obs., on 22 April by Hunters Hill Obs. and KLENOT, and on 23 April by LINEAR. It has an MOID of 0.012 AU with Mars. | ||||||
| 2002 VO69 Apollo | 106 m/yd | 22.52 | 23.0 2002-V54 | 0.05528 AU | ||
| 2002 VO69 was reported this last week as observed on 5 Nov. 2002 by NEAT/Palomar. This added three observations and 5.942 days to what had been a 27-position 3.061-day observing arc. This object has an MOID of 0.009 AU with Mars. | ||||||
| 2004 BW18 Amor | 124 m/yd | 22.18 | 22.5 | 22.5 2004-B24 | 0.04478 AU | Useful, visibility ends 30 May |
| 2004 BW18 was reported this last week as observed on 13 April with the ANU 1.0m telescope. | ||||||
| 2004 HZ Apollo has impact solutions | 126 m/yd | 22.14 | 22.7 | 22.8 2004-H34 | 0.00016 AU | |
| NEW: 2004 HZ was discovered on 19 April by LINEAR, was confirmed on 19 April by Obs. Astronomico de Mallorca (OAM, see April 21st "cover"), and on 20 April by Desert Moon Obs. and Sabino Canyon Obs., and was announced in MPEC 2004-H34 of 20 April. This object was also observed on 20 and 22 April by LINEAR, on 21 April by KLENOT, on 23 April by Great Shefford Obs., and on 24 April by Consell Obs. | ||||||
| 2004 HG12 Apollo | 135 m/yd | 21.99 | 22.4 | 22.9 2004-H47 | 0.02566 AU | |
| NEW: 2004 HG12 was discovered on 21 April by LINEAR, was confirmed on 21 April by Great Shefford Obs., and on 22 April by Sabino Canyon Obs., and was announced in MPEC 2004-H47 of 22 April. This object was also observed on 21 April by KLENOT and on 22 April by LINEAR and Great Shefford Obs. | ||||||
| 2004 EK1 Apollo | 140 m/yd | 21.92 | 22.1 | 22.1 2004-E48 | 0.03503 AU | Necessary, visibility ends 13 May |
| 2004 EK1 was observed on 16 April by Carl Hergenrother from Whipple Obs. and on 20 April by Jornada Obs. | ||||||
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| Risk monitoring - panel 1/2 | Major News for 25 April 2004 |
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The Sunday Daily Orbit Update MPEC (DOU) includes positions for 2004 HD2 from Mt. John Observatory in New Zealand yesterday, and this object, which was removed two days ago, is now back on the JPL Current Impact Risks page with one low-rated impact solution beyond the NEODyS 2080 time horizon. (Yesterday's DOU had 2004 HD2 observations from LINEAR in New Mexico from the 22nd and 23rd.) Today's DOU doesn't report new data for 2004 HK33, which JPL posted yesterday evening in Pasadena, after midnight UT, and which NEODyS posted early this evening in Pisa. Only JPL has had 2004 HF12 listed, and today removed it after observations from Consell and Great Shefford observatories last night in Europe. Another JPL-only listing, 2004 HM is in the DOU from Begues Observatory in Spain and Consell, and today JPL slightly lowered its low risk assessment for this small object that is today's "cover" subject above. |
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| Risk monitoring - panel 2/2 | Major News for 25 April 2004 |
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Consell also reported 2004 HZ and 2004 HQ1 from last night. Today both risk monitors further cut their counts of impact solutions for 2004 HZ but slightly raised their overall risk ratings for it. 2004 HQ1's low ratings had only small changes, and moved slightly lower at NEODyS. Missing from the DOU, besides 2004 HK33, are active concerns 2004 GE2, 2004 HE12, and 2004 HW. At just before 2200 UT, the Minor Planet Center Last Observation page is showing that 2004 HK33 was caught this morning by Wykrota Observatory in Brazil. 2004 GE2's visibility ends in two days, according to the European Spaceguard Central Node Priority List, which, at last check today, doesn't presently list any of the other seven objects with impact solutions that have been in recent view. |