These are the
types of worlds so far observed:
ROASTERS: gas planets in close orbits detected
by rhythmic starlight shift but not directly seen, so their mass
and orbit can be deduced but not their dimensions.
TRANSITTERS: roasters which pass in front
of their star so that their dimensions can be seen more clearly.
ROCK WORLD ‘SUPER EARTHS’: smaller
planets detected by both of the above means whose mass and dimensions
suggest that they may be made of rock. But most are many times larger
than this Earth.