News - February 2003

02/28/2003

D. K. Lynch, R. W. Russell, and D. L. Kim (The Aerospace Corporation), M. L. Sitko (Univ. of Cincinnati) and R. B. Perry (Langley Research Center, NASA) report about their 3-14-micron spectroscopy of comet C/2002 Y1 (Juels-Holvorcem) on Feb. 20.6 UT. The spectrum was a smooth and featureless continuum with a 8-14-micron temperature of about 280 ± 20 K (roughly 12 times higher than the radiative equilibrium blackbody temperature). Further informtion can be found in IAUC 8083. (IAUC 8083)

02/24/2003

A first ground-based post-perihelion observation of comet C/2002 V1 (NEAT) was reported by M. Mattiazzo (Australia). His rough estimate placed the comet at about 2^m. (Comets Mailing List)

02/19/2003

Comet C/2002 V1 (NEAT) makes an impressive sight in the SOHO/LASCO C3 images. It is quite bright although not as bright to be seen in daylight: Several attempts to observe the comet at local noon around perihelion were unsuccessful and support the prediction that the maximum brightness was indeed fainter than -2^m. The comet should now become fainter and move into southern skies.

02/17/2003

The last known brightness estimation of comet C/2002 V1 (NEAT) made on the morning of Feb. 16, by J. J. Gonzáles Suárez showed a uncertain value of -0.5^m. Due to the low height (2 degrees) the brightness is uncertain by at least 0.5^m. Comparison "star" was Mercury, a correction for differential extinction was made. With this the comet is still in the region of a maximum brightness of von -1^m. In the available images of the SOHO/LASCO C3 coronagraph the brightness is hard to estimate since the comet saturates the pixels of the detector. (Comets Mailing List)

02/16/2003

At about 16:00 UT comet C/2002 V1 (NEAT) will become visible in the C3 images of the SOHO/LASCO coronagraph. The publicly available images will be most likely saturated due to the brightness of the comet, but other images with much shorter integration times and different filters will be taken, too. The comet will leave the field of view of the C3 images on Feb. 20. The apparent path of the comet in the SWAN images and in the C3 field of view can be found in this SOHO Hotshot.

02/13/2003

The LINEAR survey discovered the first asteroid with an aphelion inside the orbit of the Earth on Feb. 11, 2003. The 17^m asteroid A/2003 CP₂₀ has an aphelion distance of 0.978 AU while the perihelion distance of Earth is 0.983 AU. The object was discovered near its maximum possible elongation of about 76°. The minimum possible distance to Earth is about 0.19 AU, to Venus 0.05 AU. (MPEC 2003-C63)

02/12/2003

C/2020 V1 (NEAT) brightens rapidly but disappears now in the evening sky. From Feb. 16 - 20, the comet will be visible in the SOHO C3 images. The now extrapolated maximum brightness may be around -1^m. A disintegration is still possible. The comet was an easy object low in the evening sky: A selection of images can be found at the Amtsgymnasiet Sønderborg, Denmark and by Ginger Mayfield, Colorado, USA an image with a fixed digital camera. (Comets Mailing List)

02/08/2003

A new orbit determination for comet C/2003 A2 (Gleason) with prediscovery observations by NEAT (found and measured by S. Hönig and R. Stoss) show that it moves on a slightly hyperbolic orbit. The perihelion distance of about 11.4 AU is the largest for a comet until now. (MPEC 2003-C47)

02/04/2003

One SOHO comet received an orbit and a designation: C/2003 B1 (SOHO) is the 38^th member of the Meyer group, found by X.-M. Zhou. SOHO has now found 547 comets. (MPEC 2003-C23)

02/02/2003

New observations of the still unnamed comet C/2002 A2 show that it is most likely a long-periodic comet and not a Centaur as previously suspected. The new orbit indicates a perihelion distance of about 11.4 AU which will be reached in January 2004. Still several solutions are possible and it will need a longer arc to be sure about the orbit of this object. (MPEC 2003-C07)

02/01/2003

Three SOHO comets received orbits and designations: C/2002 V5 (SOHO) is the 15^th member of the Marsden group, found by R. Matson. C/2002 X6 (SOHO) was found by R. Kracht, C/2002 Y2 (SOHO) by R. Matson. The two latter comets increase the number of Meyer group comets to 37. SOHO has now found 546 comets. (MPEC 2003-C02)
R. W. Russell, D. K. Lynch, and D. L. Kim (The Aerospace Corporation), M. L. Sitko (University of Cincinnati) and W. Golisch (NASA Infrared Telescope Facility - IRTF) report about the results of infrared spectroscopy of comet C/2002 X5 (Kudo-Fujikawa) on Jan. 9.1 and 10.05-10.14 UT. A relatively smooth thermal-emission spectrum, over most of the spectral range (3-14 microns) was observed, the shape resembling a blackbody near or slightly above the blackbody radiative equilibrium temperature of 340 K. If a silicate emission feature was present it would be no more than about 15 percent of the continuum. More details can be found in IAUC 8062. (IAUC 8062)