A neutron star, on the other hand, would show a transverse velocity comparable to the velocity dispersion measured for the stars of 100kms -1.
If the distance is 3kpc, the pulsar has moved 16pc at a transverse velocity of 900kms -1.
In most cases the transverse velocity of the star is unknown.
The transverse velocity would have to be as much as ten per cent or so of the radial velocity if it were to miss us.
The transverse velocity is the component of velocity along a circle centered at the origin.
It is considerably farther away than either of those stars, however, which means its transverse velocity is greater.
Combining the proper motions with distances derived using the photometric parallax method, the transverse velocity of these stars can be calculated.
Finally, both transverse velocity and distance are notoriously difficult to measure for objects which are not relatively nearby.
Measuring transverse velocities and distances accurately and without biases remains challenging, though, and sets of derived values for and frequently disagree.
In 1993, the transverse velocities were being measured within the high pressure natural gas environment using hot wire technology to accomplish the data fit.