Have you seen a bright light, flash, or flare in the sky during a few seconds? Did you think you saw a UFO? You are probably a witness of an Iridium flare.
Iridium Flares: bright lights, flashes, or flares in the sky
A large group of satellites orbits the Earth to provide voice and data coverage. Such a group is known as Iridium Satellite Constellation.
"The constellation consists of 66 active satellites in orbit, and additional spare satellites to serve in case of failure".[1]
Iridium satellite. This image, which was originally posted to Flickr.com, was uploaded to Commons using Flickr upload bot on 19:16, 7 April 2009 (UTC) by Kozuch
"With only a normal brightness of +6 magnitude (binoculars are useful to spot it), occasionally some of the Iridium satellites provide reflective flares/glints of magnitude (-)8. For comparison, Venus can be as bright as magnitude (-)4.9, thus reflections can be up to 30 times brighter than Venus. The flares/glints can last anywhere from 5 to 20 seconds before the satellite once again becomes almost invisible to the naked eye. Some flares have been observed during the daylight hours which is very unusual for reflective glares from satellites".[2]
A simulated animation of a typical Iridium flare. Author: Icycomputer.
Although not easy to observe, there are some applications to predict the Iridium flares. We have collected a couple of them:
