bannercomete

THE SPECTRA OF COMETS


Introduction - Linear 2000WM1



Spectrum of comet LINEAR 2000 MW 1
In the picture 1 is shown the spectrum of comet C/2000 WM1. Even if this comet was a 6th mag object, the spectrum is faint because only few of the light of the comet can enter the narrow slit of the spectrograph. The coma of this comet, as seen in a binocular, was about 10ĺ while the slit covered only 2x30ö over the sky. Moreover the sky was a little cloudy masking the comet's spectrum and reflecting more light from the nearby town.
Nevertheless we can see the three Swan bands (the yellow one is partially overlapped by the Hg emission from street lamps) and CN band superposed to the reflected solar continuum.
The comet was at a distance from sun of 1,18 AU and was so bright only because it was rather close to earth, only 0,32 AU from earth.

Picture 1: Spectrum of comet C/2000 WM1 (Linear) registered on 3.83 dec. 2001 with 10 min exposure for each one of the three spectral fields necessary to cover the full 3800-6500 ┼ range with 5 ┼ resolution. Lack of data around 5800 ┼ is due to missing overlap between spectral fields.
The telescope we used is a Cassegrain 0.6 m reflector at F/20 thus the slit spans 30x2 arc seconds with the long size aligned with R.A.
The spectrograph is equipped with a f=300 collimating spherical mirror, a 600 lines/mm grating and a 50 mm focusing lens camera. Dispersion on CCD is 2,6 ┼/pixel . The CCD is an MX5 12 bit 512x290 camera.


Go to introduction or other comets spectra:

Introduction

-- ATTENZIONE -->


[ Osservatorio Astronomico | Home page Cittadella di Scienze della Natura ]

1996-2002© Società Astronomica G.V.Schiaparelli - l'uso di testi, immagini e dati numerici è consentito solo per consultazione e scopo personale. Per ogni altro utilizzo richiedere autorizzazione a:

SocietÓ Astronomica G.V.Schiaparelli



28/02/2002