MBK Team's Extinction Calculator|
When comets are observed at high zenithal distances (low in the sky) the absorption of light of objects (comparison stars and the comet) is different if they are seen at different elevations. A differencial extinction correction must then be applied.
This tool calculates the atmospheric extinction. You must supply your site's altitude and the object's elevation. After you press "Calculate" you get three results for the atmospheric extinction. You use "Winter extinction" if you observed in dry, winter-like conditions, "Summer extinction" if you observed in humid, summer-like conditions or "Average extinction" if you observed in average conditions.
Calculations are based on the paper by Green DWE: Magnitude Corrections for Atmospheric Extinction. ICQ 14 (1992): 55-9, available at http://cfa-www.harvard.edu/icq/ICQExtinct.html.
If you have any comments please write to MBK Team.
International Comet Quarterly
Slovenian Comet Observation Report
Crni Vrh observatory
JPL Comet page
German Comet pages
British Astronomical Association Comet Section
Association of Lunar and Planetary Observers
Belgian Comets Workgroup
Gary Kronk's Comet and Meteor Shower page
Seichii Yoshida comet pages
Gordon Garradd's comet page