Iridium Flare

Iridium is a constellation of more than 70 communications satellites that are continuously circling the Earth. Iridium flares occur when sunlight reflects off an antenna of one of the satellites; they last only a few seconds and look like a slow-moving meteor. These flares can be as bright as magnitude -8, and can easily be seen even from the city! I photographed this magnitude -6 flare from a dark site outside of Phoenix. This photo is actually an in-camera double exposure of the same scene; I did one exposure to capture the twilight horizon, then opened the shutter again later that night at the time of the flare.

Iridium flares are much easier to view and photograph than meteors, because they can be accurately predicted! The Heavens Above web site can tell you what flares will be visible from your location. You can pick from a list of major cities, but since Iridium flares are very location-sensitive, enter your exact location in latitude and longitude (preferably within 0.01 degree of latitude and longitude, or about 1 kilometer). The site will tell you exactly when and where to look for each flare, as well as how bright it will appear. One hint: the orbits do change over time, so be sure to download a fresh prediction within a day or two of when you plan to observe. Good luck and good viewing!

Location: Maricopa, Arizona.
Date: June 28, 2003.
Time: 8:36 p.m. (twilight exposure) and 10:28 p.m. (flare exposure) MST.
Camera: Olympus OM-1 35mm SLR on fixed tripod.
Film: Fuji Provia 100F slide.
Focal length: 50 mm.
Aperture: f/4.
Exposure time: 15 seconds (twilight exposure) and 20 seconds (flare exposure).
Scanner: Nikon Coolscan LS-10E.