Astronomers have for the first time observed the collision of two ice-giant planets in a distant solar system, a process they believe planet Earth underwent when it was just a few million years old leading to the creation of our moon.
The international team, which included an LCO scientist, says the collision has revealed the signature of a new type of astronomical object - a synestia, which is composed of a cloud of molten and vapourised rock and shaped like a doughnut.
Their findings, published in Nature, have shown that the synestia resolves the mystery of a star fading unexpectedly, revealing how the fading occurred after a collision between two planets orbiting the distant star.
The study started with an alert from the the All-Sky Automated Survey for Supernovae (ASAS-SN) that a star had unexpectedly dimmed. The team suspected this to be from a planet orbiting that star.
Dr Edward Gomez, one of the paper’s co-authors, astrophysicist and LCO Education Director, said: " After the alert, we decided to take a longer look at this star with the Las Cumbres Observatory (LCO) global telescope network. This revealed the light from the star was dimming in an wholly unexpected way.”
Lead author of the study, Dr Matthew Kenworthy from Leiden Observatory, added: “Out of the blue, an astronomer on social media pointed out that the star brightened up in the infrared over a thousand days before the dimming happened. I knew then that this was an unusual event."
