Comet 17P-HOLMES
Pic du Midi Observatory
105 cm and 60cm Telescopes

Evolution of the coma at the early stage of the burst
T1M F/5, Filter = Shott RG695

Color image showing the C2 shell October 25th 3h30
T1M F/5
Blue = B Johnson
Green = C2 5125 Å fwhm = 125 Å
Red = R Johnson

Dust streams behind the nucleus, october 28th 21h Filter Shott RG695
T1M F/17, Image processing : rotational gradient with alpha = 10 °

Dust streams behind the nucleus, october 31th 5h30 Filter Shott RG695
T1M F/5 , Image processing : rotational gradient with alpha = 10 °

Dust streams behind the nucleus, october 31st 19h Filter Shott RG695
T1M F/5 , Image processing : rotational gradient with alpha = 7.5°

Animation showing the dust expansion made with images from Oct 26th to Nov 12th
Filter Shott RG695    T1M F/5
Image processing : left rotational gradient with alpha = 7.5°, right rotational unsharp mask

False color image of 17P Holmes, T60 Pic du Midi Observatory
Blue = CN 3870 Å fwhm = 50 Å
Green = C2 5125 Å fwhm = 125 Å
Red = 4430 Å fwhm = 40 Å
Boris GAILLARD, Martine CASTETS, Françoise COLAS

Deep blue image of 17P Holmes, T60 Pic du Midi, 2007 november 2nd
Boris GAILLARD, Martine CASTETS

Dust streams behind the nucleus, november 12th 23h Filter Shott RG695
The expansion is clearly visible, the center part is now clear of initial dust, the nucleus is less active
T1M F/5 , Image processing : rotational gradient with alpha = 7.5°
François COLAS, Boris GAILLARD

The comet is now clearly disconected from the "blob" visible on the left.
The "pseudo nucleus" is still 3 magnitudes brighter than before the burst.
T1M F/5 , Image processing :10 image of 5 min exposure
François COLAS, Frederic VACHIER, Agnieszka KRYSZCZYNSKA

The comet 29P Schassmann Wachmann 1 had an outburst on december 2007 and an other one on january 2008.
The similaryity with 17P outburst is impressive !
T1M F/5, image processing: median filter of 15 images. The exposure time of individual image is of 5 min.
François COLAS, Jean LECACHEUX

Station de Planétologie des Pyrénées Jean LECACHEUX, François COLAS, Boris GAILLARD CNRS-PNP      Observatoire de Paris-IMCCE-LESIA    Observatoire Midi-Pyrénées-Pic du Midi