PROSPECTS FOR DETECTION OF EXTRA-SOLAR GIANT PLANETS BY NEXT-GENERATION TELESCOPES

THE construction of several large ground-based telescopes(1,2) and the anticipated launches of new space-based ones(3-5), have prompted rene wed interest in the means by which extra-solar planets might be discov ered(1,6,7-11). The direct detection of light from such a planet would be the most compelling means of discovery, and it may soon be technic ally feasible(1,6). Jupiter has traditionally been used as a benchmark for observability, but extrasolar giant planets could have a wide ran ge of masses and ages(12), and could be significantly brighter than Ju piter. Here we present calculations estimating the optical and infrare d fluxes of extra-solar giant planets with a range of ages, and demons trate the conditions under which they will be observable with several new telescopes. Giant planets with masses greater than that of Jupiter , and younger than about 1 billion years, are the best targets, and th ey should be visible using the generation of telescopes now under cons truction.