Unraveling the planet-forming materials around young stars with JWST
In his thesis, Aditya Mahadeva Arabhavi explores the dusty nurseries where planets are born around the most common, very low-mass stars in our galaxy. Using the powerful James Webb Space Telescope (JWST), it is possible to peer into these swirling disks of gas and dust, the building blocks for new worlds. Mahadeva Arabhavi found a surprising richness of organic molecules, the very ingredients for life, even around a faint star. This discovery suggests that planets forming in these regions may be seeded with a wide variety of building blocks.
When looking specifically at ten such stars, Mahadeva Arabhavi found that while many shared similar molecules like hydrocarbons, their overall chemical makeup wasn't uniform. This diversity indicates that different planetary systems can have very different chemical starting conditions.
One of the biggest mysteries appeared to be water, as it seemed to be missing from these disks. Using systematic studies, Mahadeva Arabhavi discovered that water wasn’t absent; it was simply hidden, outshone by brighter carbon-based molecules. This means a substantial amount of water is present in these planet-forming regions where Earth-like planets form.
Finally, Mahadeva Arabhavi used computer models as virtual laboratories to understand why there is such a variety of chemistry. He found that the absolute amounts of carbon and oxygen, not just their ratio, fundamentally change the appearance of the disk. This work shows that by combining JWST's incredible data with detailed modeling, we can truly begin to understand the chemical recipes that create planets across the Galaxy.