Scientists have witnessed the earliest stages of planet formation ever observed, watching hot minerals crystallize into solid particles around a baby star 1,300 light-years away.
Image: This is HOPS-315, a baby star where astronomers have observed evidence for the earliest stages of planet formation. Image credit: ALMA(ESO/NAOJ/NRAO)/M. McClure et al.
Scientists have witnessed the earliest stages of planet formation ever observed, watching hot minerals crystallize into solid particles around a baby star 1,300 light-years away. This discovery, published in Nature, marks the first time researchers have caught a planetary system at the very moment when planets begin to form—providing a cosmic time machine to study our own solar system’s birth.
The breakthrough came from studying HOPS-315, a young star surrounded by a swirling disc of gas and dust called a protoplanetary disc. Using the James Webb Space Telescope and the Atacama Large Millimeter Array (ALMA), astronomers detected silicon monoxide (SiO) transitioning from gas to solid crystalline minerals—the crucial first step in planet formation.
A Window to Our Past
“For the first time, we have identified the earliest moment when planet formation is initiated around a star other than our Sun,” explains Melissa McClure, lead author from Leiden University. The finding offers unprecedented insight into how rocky planets like Earth come to exist.
In our solar system, similar crystalline minerals are found trapped in ancient meteorites—primordial rocks that scientists use to date when our solar system began forming. These meteorites contain the same silicon monoxide compounds now being observed around HOPS-315, but in their fully solidified state.
Co-author Merel van ‘t Hoff from Purdue University describes their discovery as “a picture of the baby Solar System,” noting that “we’re seeing a system that looks like what our Solar System looked like when it was just beginning to form.”
The Birth Process Revealed
