Trivia

Hard

Brief Bright Flashes In The Night Sky Called “Iridium Flares” Are Caused By?

Solar Flares
Satellite Antennas
Dying Comets
Blackholes Collapsing
Photo of an iridium flare taken in Perschling, Austria.
Peter Nussbaumer/Wikimedia

Answer: Satellite Antennas

If you gaze up at the night sky long enough, you’re bound to see an interesting thing or two. Shooting stars, occasional atmospheric disturbances, and every once in a great while, a brilliant flash that might catch an ordinary viewer off guard.

These bright flashes aren’t a natural phenomenon, however, but a side effect of the large network of 66 communication satellites that make up the Iridium satellite constellation (that provides global service to satellite-based phones, pagers, and integrated transceivers). The vast majority of satellites in the night sky are completely invisible to us thanks to their small size and lack of large reflective surfaces. The satellites in the Iridium constellation, however, feature large door-sized antennas covered in a polished and highly reflective material.

Most of the time, the alignment of the satellites is off just enough so that they don’t reflect sunlight towards Earth, but when they do, the reflection shines down like a giant flashlight. For a brief moment, they are the brightest thing in the night sky—each flash is visible over a 6.2 mile (10 kilometer) diameter area below. The flashes can be so bright they even, rarely, appear to viewers during the daytime who happen to be looking at the right place at the right time in the sky above.

Trivia

Hard

Alcohol Is Banned As A Performance Enhancing Drug In Which Of These Sports?

Trivia

Easy

The Invention Of Which Of These Things Was Critical To The Rapid Adoption Of The Telephone?

Trivia

Hard

The Periodic Table Of Elements Was Inspired By What?

Trivia

Easy

Where Is The World’s Largest LAN Party Held?

Trivia

Hard

When Her Reign Is Over, How Do Worker Bees Kill Off The Queen Bee?

Trivia

Easy

Which Classic Board Game Was Originally Paper Based?

Trivia

Easy

Which Film Was The First Summer Blockbuster?

Trivia

Hard

Before The Word Scientist Was Coined, Scientists Were Called What?

Trivia

Hard

The First Animated TV Show Based On A Comic To Win An Emmy Award Was?

Trivia

Very Hard

Which Company Had A Training Game Built By SimCity Creators?