QSO J1427+3312
QSO J1427+3312 is a radio-loud quasar that lies at a redshift z=6.12. This object is one of the highest redshift radio-loud quasars discovered. Observation of QSO J1427+3312 suggests that it might be a compact symmetric object that is surrounded by a dense interstellar medium in the host galaxy.
The brightness temperature of QSO J1427+3312 is of order 107 to 108 K.