News - September

09/30/2002

Comet C/2002 O4 (Hönig) shows hints of disintegration. Latest observations show the comet as a very diffuse and visually not easy object at about 9.5^m. The comet has nearly the same shape as comet C/2002 O6 (SWAN) at the time of its disintegration. An image by Michael Jäger of Sep. 29, can be found in the Image Gallery. Further observations are strongly encouraged. (Comets Mailing List, e-mail)

09/26/2002

Comet 46P/Wirtanen seems to be in outburst. Ken-ichi Kadota (Ageo, Saitama, Japan) captured this comet with CCD on Sep. 24.80 at about 9.6^m (communicated by H. Sato) and Juan José Gonzáles Suárez (Puerto de Aralla, Leon, Spain) was able to observe it on Sep. 26.19 visually despite the bright moon at about 8.7^m. Compared to the last observations in the first half of September this indicates an outburst by about 1.5^m. (Comets Mailing List)
Z. Sekanina has improved his fragmentation model for comets C/2002 Q2 (LINEAR) and C/2002 Q3 (LINEAR). The derived separation time of C/2002 Q3 from C/2002 Q2 is 1970.2 (± 1.2 yr) at a distance of about 56 AU from the Sun. The separation velocity was about 0.18 m/s. Additionally a fragmentation scenario for C/2003 Q3 and its components has been derived, too. Now four individual fragments have been identified (A to D) with A being the primary component. Component C seems to have separated from A in 1973 (± 4 yr) at about 52 AU from the Sun (separation velocity 0.1 m/s). It may be possible that C separated from C/2002 Q2 directly at the same time as component A did. Component D seems to broke off on 2002 July 5 ( ± 2 days) at about 1.5 AU from the Sun (separation velocity 1.3 m/s). The history of component B remains unclear. Predicted separation distances (and position angles) for components C and D relative to A can be found in the IAUC. (IAUC 7978)

09/23/2002

For six SOHO comet orbits and designations were announced: C/2002 R4 (SOHO) is the 14^th member of the Marsden group and was found by R. Kracht, C/2002 R5 (SOHO) is not a member of a known group but may be related to C/1999 R1 (SOHO) and was found by R. Matson, C/2002 R6 (SOHO) and C/2002 R7 (SOHO) are Kreutz group comets which were found by D. Evans and J. Sachs, respectively. C/2002 R8 (SOHO) is the 32^nd member of the Meyer group and was found by R. Kracht. C/2002 S3 (SOHO) is a Kreutz group comet found by X. Leprette and S. Hönig. SOHO has now found 518 comets. (MPEC 2002-S35, MPEC 2002-S36)

09/20/2002

A first orbit for comet C/2002 S1 (Skiff) shows a perihelion already in May 2002, at about 2.6 AU. (MPEC 2002-S31)
Comets P/2002 Q4 (Brewington) and P/2002 R1 (Shoemaker 3) received the permanent designations 154P/Brewington and 155P/Shoemaker 3, respectively.

09/18/2002

Quite a bright SOHO comet is currently visible in LASCO/C3 images. Comet C/2002 S2 (SOHO) was found yesterday by S. Hönig and is a member of the Kreutz group. This is SOHO's 512^th comet. (MPEC 2002-S17)

09/17/2002

New Discovery!: Another new comet was discovered on Sep 17, 2002, by the LONEOS survey. Comet 2002 S1 is as bright as 18^m. No orbit is available yet. A search ephemeris should be available soon on the NEO Confirmation Page. LONEOS has now found 23 comets. (IAUC 7972)

09/15/2002

New Discovery!: On Sep 04, 2002, the LONEOS survey discovered an apparently asteroidal object which was posted on the NEO Confirmation Page due to its unusual motion. Several observers were then able to detect a small coma. The 17^m comet C/2002 R3 (LONEOS) will - according to the first orbit - pass perihelion June 14, 2003, at about 3.9 AU. The comet may reach 16^m in Summer/Fall 2003. LONEOS has now found 20 comets. (IAUC 7970, MPEC 2002-R75)

09/13/2002

As predicted according to a formula by J. Bortle comet C/2002 O6 (SWAN) did apparently not survive its perihelion passage. According to photographic observations by M. Jäger the comet shows a cigar-shaped coma. Visual observations in the previous days even failed to detect the comet which was as bright as 6-7^m the weeks before. The brightness remains unclear - it is possible that the comet is now fainter than 12^m. (e-mail, Comet Mailing List)
Recovery!: T. Oribe and A. Nakamura independently recovered comet P/1986 A1 (= 1986a = 1985 XVIII) = P/2002 R1 (Shoemaker 3) on Sep. 9 and 12, 2002, respectively. The correction to the prediction of the 18^m comet is -0.14 day. The comet will pass perihelion on Dec. 14, 2002, at about 1.8 AU. It may become as bright as 13^m in January 2003, well observable in opposition to the Sun. (IAUC 7969, MPEC 2002-R69)

09/12/2002

The 13^th member of the Marsden group was detected by R. Kracht in SOHO images of Sep. 2, 2002. C/2002 R1 (SOHO) is the first Marsden group comet since February 2000. SOHO has now found 511 comets. (MPEC 2002-R57)
With more astrometric data the orbit for comet P/2002 Q1 (Van Ness) changed into a short-periodic one. The comet already passed perihelion in mid-July 2002 at about 1.5 AU. It has a period of about 6.6 years. (MPEC 2002-R52)
The LONEOS team discovered another so-called damocloid, an asteroid moving on a long-periodic cometary orbit. 2002 RP₁₂₀ was found on Sep. 04, as a 17^m bright object. It reaches perihelion at the beginning of October 2002, at about 2.5 AU and may then beocme as bright as 15^m. The period of this asteroid is about 328 years. The object should be monitored closely for the possible onset of cometary activity. (MPEC 2002-R43)

09/08/2002

Three SOHO comets received orbits and designations: C/2002 Q12 (SOHO), C/2002 Q13 (SOHO) and C/2002 Q14 (SOHO) were all found by D. Evans and are members of the Kreutz group. SOHO has now found 510 comets. (MPEC 2002-R34)

09/06/2002

The recently discovered comet pair C/2002 Q2 (LINEAR) and C/2002 Q3 (LINEAR) tends to split further. Observations at Mauna Kea by D. Jewitt revealed two further fragments for comet C/2002 Q3. Z. Sekanina reports that according to a model developed by him and P. W. Chodas the separation of Q3 from Q2 took place at 1969.2 +/- 5.1 yr at a distance of about 57 +/- 6 AU from the sun with a separation velocity of only 0.15 +/- 0.04 m/s. Due to the limited information on the Q3 fragment system until now several scenarios for this system are possible. Meanwhile C/2002 Q2 seems to have been observed visually at about 12.5^m by. R. Bouma and E. van Dijk as a very diffuse object. Confirmatory observations are needed. Further to this Michael Jäger reports that he has found pre-discovery observations of these two comets of August 21, 2002. (IAUC 7966, MPEC 2002-R20, Astrosite Groningen, pers. comm.)

09/02/2002

Another three SOHO comets received orbits and designations: C/2002 Q9 (SOHO) is a non-group comet found by R. Kracht, C/2002 Q10 (SOHO) is the 10^th member of the Kracht group, found also by R. Kracht and C/2002 Q11 (SOHO) is a Kreutz group comet found by J. Sachs. SOHO has now found 507 comets. (MPEC 2002-R02, New comet groups)