Naked Universe of Ana

How to discover a orphan planet?

Added 2024-06-27 13:28:38 +0000 UTC

While orphan planets don't orbit stars, they still move freely in interstellar space under the influence of gravity. These planets are like cosmic wanderers that follow no rules.

They are detected using gravitational microlensing:

Sometimes the trajectory of an orphan planet takes it between Earth and a distant background star the pic). When this cosmic lone wolf crosses paths, its gravity bends the light from the background star, temporarily increasing its brightness. It's as if the universe is saying: "Hey, look at this drifter!"

This cosmic photobombing lasts from several hours to several days until the orphan planet passes out of sight. Such coincidences are rarer than finding a clean public restroom, so astronomers observe millions of stars simultaneously, hoping to catch these interstellar rebels.

Pic credit: MARK GARLICK / SCIENCE PHOTO LIBRARY