Oddball exoplanets raise new questions about how solar systems form
With a mortar and pestle, Christy Till blends together the makings of a distant planet. In her geology lab at Arizona State University in Tempe, Till carefully measures out powdered minerals, tips them into a metal capsule and bakes them in a high-pressure furnace that can reach close to 35,000 times Earth’s atmospheric pressure and 2,000° Celsius.
In this interplanetary test kitchen, Till and colleagues are figuring out what might go into a planet outside of our solar system.
“We’re mixing together high-purity powders of silica and iron and magnesium in the right proportions to make the composition we want to study,” Till says. She’s starting with the makings of what might resemble a rocky planet that’s much different from Earth. “We literally make a recipe.”
Scientists have a few good ideas for how to concoct our own solar system. One method: Mix up a cloud of hydrogen and helium, season generously with oxygen