A.other stars have planets more or less like the one going around the sun
B.other stars have planets with bigger orbits
C.the way planets orbiting around the sun in our solar system is quite unique
D.planets in other systems have elongated orbits
A.it is either a star or a planet
B.it was formed like a star and orbits like a planet
C.it helps us change the definition of"planet"
D.it cannot be explained satisfactorily by conventional theory
A.New Planetary Puzzlers
B."Hot Jupiters" Challenging Conventional Theory
C.A Redefinition of"Planet"
D.Two Remarkable Finds
A.they are unaware of the consequences of what they are doing
B.they are reluctant to sacrifice their own economic interests
C.time has not yet come for them to put due emphasis on it
D.it is difficult for them to take effective measures