ARE Jupiter and Saturn, the gas giants of the Solar System, Earth’s larger
siblings or could they be interlopers that drifted in from deep space billions
of years ago? For the first time astronomers have analysed the light spectra
from planet-sized balls of gas floating free in space, and found them remarkably
similar to that of a primordial Jupiter.
Earlier this year, Rafael Rebolo and his colleagues at the Institute of
Astrophysics in the Canary Islands managed to identify 18 dim objects in the
constellation Orion which they estimate are just a few times more massive than
Jupiter but are…
