Members of the double pulsar system PSR J0737-3039 : neutron stars or   strange stars ?
  One interesting method of constraining the dense matter Equations of State is to measure the advancement of the periastron of the orbit of a binary radio pulsar (when it belongs to a double neutron star system). There is a great deal of interest on applicability of this procedure to the double pulsar system PSR J0737-3039 (A/B). Although the above method can be applied to PSR A in future within some limitations, for PSR B this method can not be applied. On the other hand, the study of genesis of PSR B might be useful in this connection and its low mass might be an indication that it could be a strange star. 
Manjari Bagchi, Jishnu Dey, Sushan Konar, Gour Bhattacharya and Mira   Dey