| Speaker: | Sihao Cheng (Perimeter Institute/IAS) |
|---|---|
| Title: | A novel view of the Milky Way disk and outer Solar System |
| Date (JST): | Thu, Dec 18, 2025, 15:30 - 17:00 |
| Place: | Seminar Room A |
| Abstract: |
Combining big survey data with advanced statistical analysis is a fruitful approach to new discoveries. I will present two examples. (1) One is a new mapping technique to provide for the first time a clear and flat view of the phase space of Milky Way disk. Applying it to Gaia data, we found sharp new structures with order-of-unity contrast in number density and metallicity. It opens a new window to study galactic dynamics, calling for theoretical explanation and observational search for similar structures in other disk galaxies. (2) Another example is a new algorithm searching for moving objects from imaging survey. Applying it to cosmological surveys, I found a dwarf planet with the widest orbit in the Solar system, which places an interesting challenge to the Planet Nine / Planet X hypothesis. |
