Cool-House Rock

It’s a bird… it’s a plane… It’s Oumuamua!!!


This is Sandra Tsing Loh with the Loh Down on Science.


In 2017, astronomers detected the first interstellar object passing through our solar system. Oumuamua! They couldn’t tell if it was an asteroid or comet, but either way, it sped right past the Sun’s gravitational pull. But how?! 


Jennifer Bergner and Darryl Seligman from UC Berkeley wondered what gave it the extra boost.


They’ve observed our Sun’s radiation hitting other comets, heating ice and producing hydrogen gas trapped inside. The gas can burst out like steam escaping a pressure cooker. Researchers tested if this happened with Oumuamua using computer simulations of recorded temperatures during its flyby.


Results? They found similar gas-producing temperatures deep inside Oumuamua as it passed our Sun. Hydrogen gas escaped ice pockets and UNLOCKED Oumuamua’s propulsion against our Sun’s gravity!


Ice within Oumuamua also suggests water exists in star systems beyond our own.


Who knew SPACE ROCKS with ICY POCKETS can make COOL ROCKETS?! We do now.


Bergner, J.B., Seligman D.Z. Acceleration of 1I/’Oumuamua from radiolytically produced H2 in H2o ice. Nature 615, 610 (2023).