Presto, Change-o, An Iridium Flare in the Sky

Reading Time: 2 minutes

My five-year-old son is a budding astronomer, so I bought him (okay, me) the Celestron Firstscope 114m Newtonian reflector scope for Xmas. Given that we are on a hilltop overlooking a dark canyon to the east, it has led to oodles of fun looking at the moon, Saturn, Jupiter, and nebulae.

Our main resource for figuring out what’s worth looking at in the sky tonight is the excellent Heaven’s Above site. It tells you what’s up there right now, where it is (azimuth/elevation), and how bright it should be.

One of the more interesting Heavens Above data nuggets, however, is on Iridium flares, moments when the flat, highly reflective surfaces of these low-earth orbit satellites reflect the sun to observers here on earth, producing a slash of bright light. There are usually a couple every few days, some of which are even visible in daylight.

To the five-year-old this is magical stuff, a predictable flash in the sky that we can prepare for days in advance. It has also led to great discussions about satellites, why things don’t fall from the sky, and how we predict such things.

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