Gravitational-Wave Astronomy Still in Its Infancy

Extreme matter & extreme environs: Other astrophysical systems physicists could explore with new detectors are neutron stars, which are the densest objects in the Universe and which have magnetic fields up to billions of tesla in magnitude. Six decades after their discovery, we still don’t fully understand the equation of state of the cores of these stars, and we don’t know the origin of their large magnetic fields. These fields could deform a neutron star causing it to emit gravitational waves, something that future observatories could uncover.

https://physics.aps.org/articles/v13/113

This could give Einstein something new to look for.