The Nancy Grace Roman Space Telescope, this 2.4-meter space telescope, equipped with a wide field IR imager, will launch in october 2026. It will perform is a 6x62 day observation of 2 square degrees of the galactic Bulge to search for planets via microlensing. Data will be publicly available with no proprietary period.

For each campaign of 62-days observations, Roman will detect ~200 bound planets down to the mass of Ganymède, including 30 with mass < 3 MEarth. While microlensing light curves themselves usually yield only the star-planet mass ratio, Euclid precursor observations of the Roman fields done in March 2025 will yield direct observations of the host star and the background source star, which can be used as a strong constraint in the light curve modelling to measure physical masses to 10 % from year-1 of the Roman galactic bulge survey. We will detect ~200+ free-floating planets per campaign, half of which with masses mass < 1 MEarth.

I will comment on the latest results on the mass function for cold planets from the ground, before giving an update of the prospects of combining Euclid and Roman observations to study their demographics, whether they are bound or rogue.