Solar chemistry suggests best places to hunt
BEIJING — Rocky planets zipping around distant stars might reveal themselves in the chemical elements missing from their host star.
Compared to stars like it, the sun contains fewer planet-building elements such as aluminum, calcium and silicon, Jorge Melendez of the University of Sao Paolo in Brazil said on August 27 at the International Astronomical Union’s general assembly meeting. “For some reason, the sun is missing these more heavy elements.” So stars like the sun might be a good place to hunt for rocky planets — and Melendez and his colleagues are doing just that.
While astronomers already knew that stars accompanied by giant planets contain more heavy elements, this work suggests that chemistry could also flag the presence of smaller, terrestrial planets.
So far, one candidate shines brighter than the rest: a star called HIP 56948, 200 light-years from Earth, whose light very closely resembles the sun&rs