Comet Hale-Bopp

This image was produced through successive use of photographic enhancement and subtraction, followed by smoothing by computer processing . When a matching, earlier exposure of the same sky field with the same telescope (on which the comet is not present) is photographically subtracted from the enhanced photo of the same field in which the comet is present, then the images of the stars should in principle cancel out, leaving only that of the comet in the field. A full cancellation is virtually impossible to achieve in practice, but if the resulting image is heavily smoothed (i.e. substituting each image element with the mean intensity of its surroundings), then the smaller images of the stars disappear and the full extent of the comet's large coma becomes visible. This false-colour photo was produced in this way by means of computer processing within the MIDAS image processing system. The images of the brightest stars could not be completely removed by this process and faint remnants are still present. (In technical terms, a 2-D low-pass Fourier filter was used to achieve heavy smoothing over approx. 16 x 16 arcsec cells).

Crédit:

ESO

À propos de l'image

Identification:eso9521c
Type:Observation
Date de publication:30 août 1995
Communiqués de presse en rapport:eso9521
Taille:908 x 774 px

À propos de l'objet

Nom:Comet Hale-Bopp
Type:Solar System : Interplanetary Body : Comet
Catégorie:Solar System

Formats des images

Grand JPEG
176,3 Kio
JPEG taille écran
178,2 Kio

Fonds d'écran

1024x768
177,7 Kio
1280x1024
263,0 Kio
1600x1200
346,0 Kio
1920x1200
341,6 Kio
2048x1536
494,6 Kio

Couleurs & filtres

DomaineLongueur d'ondeTélescope
Visible
R
665 nmESO 1-metre Schmidt telescope