News - March 2002

03/29/2002

The 416^th SOHO comet is the 11^th member of the Marsden group. C/1998 A4 (SOHO) was detected by R. Kracht. (MPEC 2002-F70)

03/28/2002

The 415^th SOHO comet is a member of the Kreutz group. C/2002 F3 (SOHO) was detected by M. Meyer. (MPEC 2002-F61)

03/22/2002

New Discovery!: An asteroidal object, discovered by LINEAR already on Feb. 07, 2002, which received the designation 2002 CW₁₃₄ has shown cometary activity as reported by M. Tichy and M. Kocer (Klet) and G. Masi and F. Mallia (Campo Catino) after placement on the NEO Confirmation Page. The comet P/2002 CW₁₃₄ (LINEAR) passed perihelion already on Feb. 28, 2002, at about 1.8 AU. The period is about 6.8 years. The comet is currently at maximum brightness with about 15^m. This is LINEARs 78^th new comet discovery. (IAUC 7858, MPEC 2002-F49)
An impressive animation of comet C/2002 C1 (Ikeya-Zhang) has been produced by M. Karrer. The 650kB animation shows very fine details and the dynamic behaviour of the tail and is worth the download. (Comets Mailing List)
Five additional SOHO comets received orbits and designations. C/1999 P6 (SOHO), C/1999 P8 (SOHO) and C/1999 P9 (SOHO) are members of the Marsden group. C/1999 P7 (SOHO) is a member of the Meyer group. All four comets were detected by R. Kracht. The Meyer and Marsden groups now consist of 13 and 10 members, respectively. R. Kracht also suggested that his find of last year, C/2001 Q7 (SOHO) may be a member of the extended Marsden group. This was finally confirmed and this group is now called the Kracht group.
C/2002 F2 (SOHO) was detected by S. Hönig and is a member of the Kreutz group. SOHO has now found 414 comets. (MPEC 2002-F43)

03/21/2002

A first and still preliminary orbit for comet C/2002 F1 (Utsunomiya) shows a perihelion on Apr. 23, 2002, at about 0.46 AU. The comet might then reach 5^m but it will be close to the sun. In the coming weeks the comet decreases its elongation and will stay within 35° until June when its brightness will be fainter than 10^m. (IAUC 7855, MPEC 2002-F39)
C/2002 E3 (SOHO) is a Kreutz comet detected by X. Leprette. This is SOHOs 409^th comet. (MPEC 2002-F35)

03/20/2002

New Discovery!: A new comet has been discovered visually on Mar. 18, 2002, by Syogo Utsunomiya (Minami Oguni-machi, Aso-gun, Kumamoto-ken, Japan). Comet 2002 F1 is about 10^m. This is Utsunomiyas third comet discovery. The comet is located in the morning twilight. Astrometric followup is urgently required. A search ephemeris can be generated on the NEO Confirmation Page.

03/18/2002

There are hints that comet C/2002 C1 (Ikeya-Zhang) may exhibit a so-called perihelion asymmetry - a phenomenon which is characterised by an unusual lightcurve with reaching the maximum brightness after the perihelion and not following the standard model of cometary brightness evolution. This can be caused by active regions on the surface of the comet which become more and more exposed to direct sunlight after perihelion leading to an increased activity. J. Bortle has analysed the presumed 1661 apparition of this comet which was the reason for him to assume a likely perihelion asymmetry. He estimates that if an asymmetry occurs then the maximum brightness may be reached at T+10 days (with T = perihelion) with about 2.0^m to T+15 days with about 1.4^m. His analysis of the 1661 apparition will appear in the March issue of The Astronomer. (Comets Mailing List)

03/17/2002

Two further archival SOHO comets, both found by R. Kracht, received orbits and designations. C/1999 N6 (SOHO) is the seventh clear member of the Marsden group. C/1999 N6 (SOHO) is a likely member of the extended population with almost the same orbital elements as C/1999 M3, but B. G. Marsden notes that the orbit solution is not unique. SOHO has now found 408 comets offcially. (MPEC 2002-F03)

03/13/2002

A first and preliminary orbit for comet C/2002 E2 (Snyder-Murakami) shows a perihelion on Feb. 22, 2002, at about 1.5 AU. The comet will remain at 10^m in March moving northward in the morning sky. (IAUC 7852, MPEC 2002-E43)

03/12/2002

New Discovery!: A new comet has been discovered visually by amateurs D. Snyder (Palominas, AZ, USA) and independently by S. Murakami (Matsunoyama, Niigata, Japan) on Mar 11, 2002. The comet was estimated at 10.5^m visually. The comet 2002 E2 moves northward. A search ephemeris can be found on the NEO Confirmation Page. (IAUC 7850)

03/09/2002

Another three archival SOHO comets received orbits and designations. C/1998 A2 (SOHO) and C/1998 A3 (SOHO) are members of the Marsden group and were found by R. Kracht. B. Marsden again noted the possibility that these comets could have orbits which differ from parabolas, making a connection with the daytime Arietid meteor stream possible, as proposed originally by D. A. J. Seargent. Marsden also noted the similarity of the longitude and latitude of the direction of the perihelion with that of comet 96P/Machholz and the Quadrantid meteor stream. The Marsden group has now six firmly established members.
C/2000 B8 (SOHO) is a member of the Meyer group and was found by M. Meyer. This group has now 12 established members. SOHO has now discovered 406 comets officially. (MPEC 2002-E25)

03/08/2002

Two SOHO comets received orbits and designations. C/1999 M3 (SOHO) is an archival non-Kreutz comet found by R. Kracht. Although the comet seems unrelated to others when looking at the orbital elements alone, it might nevertheless be loosely connected with the Marsden group. R. Kracht noted the similarity of the longitude and latitude of the direction of the perihelion with that of the Marsden group and comet C/2000 O3 (SOHO). There may exist an extended relationship between the four firm members of the Marsden group and C/2000 O3 and C/1999 M3.
C/2002 E1 (SOHO) is a member of the Kreutz group and was found by S. Hönig. SOHO has now officially discovered 403 comets. (MPEC 2002-E18)

03/02/2002

Three archival SOHO comets, all found by R. Kracht, received orbits and designations. C/1999 K16 (SOHO) and C/1999 L9 (SOHO) are members of the Meyer group which has now 11 members. C/1999 K17 (SOHO) is a member of the Kreutz group. SOHO has now officially discovered 401 comets. (MPEC 2002-E05)

03/01/2002

Seven archival and one real time SOHO comet received orbits and designations. Comets C/1997 H4 (SOHO) and C/1997 H5 (SOHO) are members of the Meyer group and were found by R. Kracht. Comets C/1998 H5 (SOHO), C/1998 H6 (SOHO) (found by S. Hönig), C/1999 H8 (SOHO), C/1999 H9 (SOHO), C/1999 J13 (SOHO) (found by R. Kracht) and C/2002 D1 (SOHO) (found by X. Leprette) are members of the Kreutz group. SOHO has now officially discovered 398 comets. (MPEC 2002-D41, MPEC 2002-D42), MPEC 2002-D45)
J. Shanklin proposed the possible identity of comet C/2002 C1 (Ikeya-Zhang) with the comet of 877 for which no orbit has been determined. C/2002 C1, which is very likely the same comet as C/1661 C1 was already observed with the naked eye. (BAA Comet Section Homepage, Comets Mailing List)
Comet 46P/Wirtanen was observed with ESO's VLT at Paranal (Chile). The comet was almost as far from the sun like it will be in 2011, when the Rosetta spacecraft will have an encounter with this comet. There is an ESO Press Release with more information about the observations and Rosetta.