MACIEJ KONACKI, CALIFORNIA INSTITUTE OF TECHNOLOGY

PRINCETON ASTRONOMY COLLOQUIUM - MARCH 2, 2004

ABSTRACT

Extrasolar Planets Big and Small

The modern incarnation of the field of extrasolar planets has emerged in 1992 with the detection of terrestrial-mass planets orbiting the millisecond pulsar B1257+12 (Wolszczan & Frail, 1992). To date over a hundred of extrasolar giant planets were found through precision radial velocity surveys. Despite many successes, the planetary system around the pulsar B1257+12 remains unique. It comprises three planets A, B and C with the orbital periods of 25, 66 and 98 days and the lower limit on the masses in the range of 0.015 to 3.4 Earth masses.

I will present the outcome of 13 years of the PSR B1257+12 observations that allow us not only to put precise lower limits on the masses of the pulsar planets but in fact measure with a stunning accuracy the true masses of planets and their orbital inclinations. I will also discuss new observational hints for what appears to be a signature of a belt type object surrounding the pulsar.

Ground based photometric surveys are among the most promising techniques that can uncover extrasolar giant planets and deliver parameters (e.g. radius) not available otherwise. Yet, only one new giant planet has been discovered so far (OGLE-TR-56b, Konacki et al, 2003), despite intense efforts. It is quite surprising and puzzling. I will discuss the ongoing photometric surveys and related problems that make such surveys much more challenging than expected.