We are imaging Gaia-selected young massive white dwarfs in the 40 pc solar neighborhood with the ESO-VLT (ERIS LGS AO instrument) to search for >5 Jupiter mass companions. These white dwarfs have 2.5-5 M⊙ Main Sequence (MS) progenitors, and offer the unique possibility to test the formation of giant planets around intermediate mass stars, assuming these planets can survive post-MS evolution of their host stars. White dwarfs feature key advantages over their progenitor MS stars to spatially resolve giant planet companions in terms of (1) contrast and (2) angular separation. We limit ourselves to young white dwarfs with total ages (MS lifetime + white dwarf cooling age) < 1 Gyr which assures that any giant planets would be self-luminous and bright enough to be detectable (H-band < 25 mag). So far, we have obtained high angular resolution data for 10 white dwarfs with VLT/ERIS, with no confirmed detections, which might imply giant planets do not form around intermediate-mass MS stars, due to the rapid photoevaporation of their circumstellar disks caused by the host stars’ elevated FUV and X-ray irradiation. We keep searching.

The giant planets of our solar system contain a record of elemental and isotopic ratios of keen interest for what they tell us about the origin of the planets and in particular the volatile compositions of the solid phases. In situ measurements of the Jovian atmosphere performed by the Galileo Probe during its descent in 1995 demonstrate the unique value of such a record, but limited currently by the unknown abundance of oxygen in the interior of Jupiter–a gap planned to be filled by the Juno mission set to arrive at Jupiter in July of 2016. Our lack of knowledge of the oxygen abundance allows for a number of models for the Jovian interior with a range of C/O ratios. The implications for the origin of terrestrial water are briefly discussed. The complementary data sets for Saturn may be obtained by a series of very close, nearly polar orbits, at the end of the Cassini-Huygens mission in 2016-2017, and the proposed Saturn Probe. This set can only obtain what we have for Jupiter if the Saturn Probe mission carries a microwave radiometer.