The largest polar jets are those seen in active galaxies such as quasars.

With a redshift of 0.051, this active galaxy is about 730 million light-years away.

These features are commonly associated with many active galaxies.

In the active galaxies, black holes are seen as having masses far greater than a billion suns.

One mystery is why some active galaxies produce copious radio waves and others none.

With a redshift of 3.77, light from this active galaxy is estimated to have taken around 11.7 billion years to reach us.

The total list of active galaxies was cut down to those within a limited distance of Earth to avoid detection problems.

The bright source in the upper left is an active galaxy in the cluster.

His fields of scientific interest include active galaxies, cosmology, and the three-body problem.

With a redshift of 5.47, light from this active galaxy is estimated to have taken around 12.3 billion light-years to reach us.