T dwarf
Videos
An object with the spectral type T is either a brown dwarf or a young free-floating planetary-mass object. A directly imaged exoplanet with a young age can also be a T-dwarf. T dwarfs are colder than
Spectra of mid to late T-dwarfs, showing absorption due to methane, water vapor, CIA hydrogen and potassium
L dwarf
Videos
An object with the spectral type L can be either a low-mass star, a brown dwarf or a young free-floating planetary-mass object. If a young exoplanet or planetary-mass companion is detected via direct
T dwarf
…brown dwarf or a young free-floating planetary-mass object. A directly imaged exoplanet with a young age can also be a T-dwarf. T dwarfs are colder than L dwarfs, but warmer than Y dwarfs. The first T-dwarf discovered was Gliese 229B, which was discovered in 1995. This object had a temperature below 1000 K and…
Spectrum of Kelu-1 (L-type binary, bottom line) in comparison to an M6-dwarf, which shows much stronger TiO and sodium absorption.
The L-type binary CWISE J0146-0508AB (L4+L8 blue)