I use radio telescopes such as ALMA and the VLA to measure the radio flux density of ultracool dwarfs (spectral type >M6), characterise the emission mechanism, and evaluate any impact on surrounding planets.
Ultracool dwarfs are small stars with effective temperatures < 2700 K. Like all M dwarfs, ultracool dwarfs tend to be magnetically active. Ultracool dwarfs may have different emission mechanisms.
Radio Emission & HAbitability
Magnetic fields and gyrosynchrotron radiation from an ultracool dwarf can threaten life on surrounding planets.
TRAPPIST-1 is an ultracool M dwarf (M8) with a system of seven planets, four of which may reside in the habitable zone. TRAPPIST-1 itself may be too magnetically active to support life on its planets.