The detection of 206s X-ray pulsations from H0253+193 indicates that the source is a compact object. It is argued here that object can not be a T Tauri star or Be/X –ray binary pulsar suggested that H 0253+193 is slowly ...

The rapid rotation rate of millisecond pulsar PSR 1937+214 suggests that it may be close to the point of rotational instability. Rotational stability implies lower limits on the mass and moment of inertia, and an upper ...