Astronomers are puzzled over an enigmatic companion to a pulsar
The mysterious entity has a mass somewhere between that of a neutron star and a black hole
![illustration of a mysterious object orbiting a pulsar](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2024/01/011724_am_mystery_space_object_feat.jpg?fit=1030%2C580&ssl=1)
An unseen object orbiting a pulsar might be an exceptionally lightweight black hole (illustrated), a very heavy neutron star, or something else entirely.
Daniëlle Futselaar/artsource.nl