A key signature in the planet population is the hot Neptunian desert, a dearth of Neptune mass planets orbiting close to their host stars. The desert has been the subject of intense study as to its origin, and is thought to arise due to a combination of tidal disruption and photoevaporation. TESS has significantly increased the population of planets inside the desert (“nomads”), making a systematic study of the population of planets in the desert possible for the first time. Known planets in the desert include TOI-849b, the remnant core of a giant planet, and LTT9779b, with more arriving regularly. The new discoveries pose a key question: what formation and evolution pathways can leave a planet inside the desert, when such pathways are not the norm?
“Nomads” is a new program studying the nature and origin of the Neptunian Desert, aiming to double the current number of nomad planets in the desert that have precisely measured masses and radii, constraining their planetary densities and compositions. The resulting sample of characterised planets will provide the basis for theoretical studies of the processes that place planets inside the desert.
In this poster, we will present an overview of the Nomads program, including the survey strategy and preliminary results. We will present new measurements of the planetary masses of several nomad planets, including an exciting new heavy Neptune, likely to be another remnant core akin to TOI-849b.