G A R Y   W.   K R O N K ' S   C O M E T O G R A P H Y

Comet C/2000 WM1
LINEAR

T. Lovejoy image of C/2000 WM1 exposed on 2002 January 31
Copyright 2002 by Terry Lovejoy (Australia)

This image was obtained by Terry Lovejoy on 2002 January 31 starting at 17:33 UT. It consists of 2 panels of 10 x 10 second exposures, using a Takahashi Epsilon E-160 530mm FL F3.3 reflector and Genesis camera (with KAF-0401E sensor). The field of view of the image is 1.3 x 0.6 degrees.

Discovery

Shortly after mid-December of 2000, the LINEAR team announced the discovery of an asteroidal object on images obtained on December 16.07. The magnitude was given as 17.8. The available positions allowed the Central Bureau for Astronomical Telegrams (the clearinghouse for observations of comets and asteroids) to determine a rough orbit, which, in turn, allowed them to link these observations to another LINEAR object detected on November 16 and 18. Interestingly, T. B. Spahr (Smithsonian Astrophysical Observatory, Mt. Hopkins) observed the object on December 20.15 and detected a coma 10 arcsec across and a broad, faint tail extending 10-20 arcsec toward PA 45°. Thus, the object was really a comet.

Historical Highlights

  • Following the recognition that this object was a comet, Brian G. Marsden (Central Bureau) calculated a parabolic orbit which indicated the comet would pass only 0.55 AU from the sun on 2002 January 22.78. This early orbit indicated the comet might reach a maximum brightness of magnitude 4.
  • After the official announcement, a few observations were made of this faint object. A. Nakamura (Kuma Kogen Observatory, Japan) estimated the magnitude as 18.1 and 18.0 on 2000 December 22 and 29, respectively. He also noted the coma was 0.25 arcmin across. A. Akahori (Matsumoto, Japan) estimated the magnitude as 17.9 and 17.6 on 2001 January 6 and 24, respectively. He gave the coma diameter as 0.15 to 0.2 arcmin.
  • The comet slowly brightened throughout the spring and summer and by the end of August the visual magnitude was slightly fainter than magnitude 13. CCD cameras were revealing a faint tail about 25 arcsec long around mid-June and this had increased to about 2 arcmin by late August and early September. As October began, the magnitude was near 11, while by the end of the month it was near 9.5.
  • The comet began brightening more rapidly in November. It began the month at magnitude 9.5 and ended the month slightly brighter than magnitude 6. Interestingly, the comet began brightening faster than expected during the latter half of November, but it is not known how long this trend will continue. Some unusual features were also becoming visible. Michael Jäger of Austria photographed a very narrow anti-tail on November 16 (see below). Other observers began detecting it during the next few days. Giovanni Sostero (Italy) was observing with an 8-inch Schmidt-Cassegrain on the 16th and "caught a structure similar to a 'jet'." He said it was 0.6 arcmin long and extended toward PA 145°.
  • The comet moved almost directly southward during the first half of December, and dropped below the horizon for most Northern Hemisphere observers shortly after mid month. As Northern Hemisphere observers caught their last glimpse of the comet, they generally estimated the magnitude as near 5, the coma diameter as about 20 arcmin, and the tail as over 1° long.
  • The comet faded slowly as it headed southward, because its increasing distance from Earth was nearly compensated by its decreasing distance from the sun. The magnitude was near 6 around the end of December and early January. The comet passed perihelion on January 22, at which time observers were typically giving the magnitude as 6.2-6.3. Although the comet should have began fading more rapidly, it surprized everyone when it was found to be experiencing an outburst on January 27. Estimates of the magnitude on that day, as well as on the 28th, placed it around 4.6-4.8. Interestingly, the comet appeared to have not been finished, as Michael Mattiazzo (Wallaroo,South Australia) found the comet near magnitude 3.0 on January 29.78. During the next few days, observers in the Southern Hemisphere saw the comet brighten to about magnitude 2.5, before it resumed fading.

  • Additional Images


    Giovanni Sostero photo of C/2000 WM1 exposed on 2001 February 16 and 17
    Copyright 2001 by Giovanni Sostero (Remanzacco Observatory-Italy)

    Images of this comet were obtained by Giovanni Sostero on the mornings of 2001 February 16 and 17. He was using a 0.3-m f/2.8 Baker-Schmidt and a Hi-Sis 24 CCD camera. The webmaster has combined these two images to illustrate the comet's motion at that time.



    Giovanni Sostero and V. Gonano photo of C/2000 WM1 exposed on 2001 September 5
    Copyright 2001 by Giovanni Sostero and V. Gonano (Remanzacco Observatory, Italy)

    This image was obtained by Giovanni Sostero and V. Gonano on 2001 September 5.9. It is a combination of 15 30-second exposures obtained with a 0.3-m f/2.8 Baker-Schmidt, a Hi-Sis 24 CCD camera, and a Cousin R filter.


    Garzia, Gonano, and Maestrutti photo of C/2000 WM1 exposed on 2001 September 9
    Copyright 2001 by Giovanni Sostero (Remanzacco Observatory, Italy)

    This image was obtained by S. Garzia, V. Gonano, and M. Maestrutti on 2001 September 9.98. It is a combination of 10 60-second exposures obtained with a 0.3-m f/2.8 Baker camera, a CCD camera, and a Cousin R filter.


    Konrad Horn photo of C/2000 WM1 exposed on 2001 September 26
    Copyright 2001 by Konrad Horn (Salem, Germany)

    This image was obtained by Konrad Horn on 2001 September 26. It is a combination of 40 60-second exposures obtained with a Gensis 100/500 telescope and an AUDINE CCD camera.


    S. Garzia, M. Maestrutti, and G. Sostero image of C/2000 WM1 exposed on 2001 October 14
    Copyright 2001 by Giovanni Sostero (Remanzacco Observatory, Italy)

    This image was obtained by S. Garzia, M. Maestrutti, and G. Sostero on 2001 October 14.04. It is a combination of 20 60-second exposures obtained with a 0.45-m f/4.5 reflector and an ST6V CCD camera. The two images on the right illustrate the brightness contours within the comet and tail.


    M. Jager image of C/2000 WM1 exposed on 2001 November 16
    Copyright 2001 by Michael Jäger (Austria)

    This image was obtained by Michael Jäger on 2001 November 16.16. It is an 8-minute exposure obtained using a Celestron Schmidt camera and TP hyp film. The image is significant in that it reveals a narrow antitail extending nearly straight downward, while a very short, diffuse main tail extends a short distance from the coma toward the upper right.


    M. Jager image of C/2000 WM1 exposed on 2001 November 21
    Copyright 2001 by Michael Jäger (Austria)

    This color image was obtained by Michael Jäger on 2001 November 21.06. It is an 8-minute exposure obtained using a schmidt camera 250/450 and fuji 160 nps prof film.


    Amtsgymnasiet image of C/2000 WM1 exposed on 2001 November 23
    Copyright 2001 by Amtsgymnasiet (Denmark)

    This image was obtained by high school students at Amtsgymnasiet and EUC Syd (Sønderborg, Denmark) on 2001 November 23.78. It was obtained using a CCD camera. This is one of the best images showing the comet's antitail. The inset is a combination of 3400 seconds and shows the antitail is split and curved. Other images of the comet obtained by this class are located on their webpage.


    M. Jager image of C/2000 WM1 exposed on 2001 December 3
    Copyright 2001 by Michael Jäger (Austria)

    This color image was obtained by Michael Jäger on 2001 December 3.75. It is an 5-minute exposure obtained using a schmidt camera 250/450 and fuji 160 npc prof. film. Note the fanned dust tail curving toward the left side of the image and the appearance of two straight gas tails extending toward the bottom center of the image.


    M. Jager image of C/2000 WM1 exposed on 2001 December 9
    Copyright 2001 by Michael Jäger (Austria)

    This color image was obtained by Michael Jäger on 2001 December 9.82. It is an 5-minute exposure obtained using a schmidt camera 250/450 and fuji 160 npc film. The fanned dust tail curves toward the left side of the image, while two straight gas tails extend toward the bottom edge of the image.


    Stewart Leffanue image of C/2000 WM1 exposed on 2001 December 10
    Copyright 2001 by Stewart Leffanue (near Mt. Pleasant, South Australia)

    This color image was obtained by Stewart Leffanue on 2001 December 10. It was obtained using a 105mm Tamron lens and Pentax camera, with 800 speed Fuji film, all riding piggyback on a C8 celestron. It is a hand guided 5 minute exposure. The main galaxy in photo is NGC 253, while the bright star is Beta Cetus.


    Buso and Mansilla image of C/2000 WM1 exposed on 2001 December 24
    Copyright 2001 Victor Angel Buso and Luis Mansilla (Argentina)

    This image was obtained by Victor Angel Buso and Luis Alberto Mansilla on 2001 December 24 (1:22:40 and 1:26:24 UT ). It is a combination of 3+3 minute exposures obtained using a PICTOR 416XT CCD camera and Schmidt 21.5-cm f/2.9 from the Observatorio Astronomico Cristo Rey - ROSARIO - Argentina. Member of the ASOCIACION SANTAFESINA DE ASTRONOMIA (A.S.A.).


    Mike Begbie (Harare, Zimbabwe) made this drawing of C/2000 WM1 on 2002 January 4
    Copyright 2002 Mike Begbie (Harare, Zimbabwe)

    This drawing was made by Mike Begbie on 2002 January 4. He was using a 15-cm f/7 refractor, 50x. Although the drawing was originally black on white, the webmaster has been reversed the colors to better illustrate the actual view.


    Mike Begbie (Harare, Zimbabwe) made these drawings of C/2000 WM1 during the period of 2002 January 31 to February 3
    Copyright 2002 by Mike Begbie (Harare, Zimbabwe)

    These drawings were obtained by Mike Begbie during the period of 2002 January 31 to February 3. Details of what instruments were used are given on each image.


    Members of Observatorio Geminis Austral (Rosario, Argentina) obtained this image of C/2000 WM1 on 2002 February 1
    Copyright 2002 Observatorio Geminis Austral (Rosario, Argentina)

    This image was obtained by José Sanchez and Victor Buso on 2002 February 1.32. They used a 25-cm refractor and a CCD camera. The total visual magnitude was then about 4.0.


    Noel Munford and Ian Cooper (New Zealand) obtained this image of C/2000 WM1 on 2002 February 3
    Copyright 2002 by Noel Munford and Ian Cooper (Manawatu Observatory, Palmerston North, New Zealand)

    This image was obtained by Noel Munford and Ian Cooper on 2002 February 3.66. It is a 6-minute exposure obtained with a 400mm f/6.3 lens and Fuji NHG II 800 film. The total visual magnitude was then about 3.1.


    C&MS Home   |  Currently Visible   |  Sungrazers   |  Comet Information   |  Comet WWW Links

    If you have any questions, please email me