Welcome to Quasars vs. Pulsars on Veritas. Whether you are an avid astrophysics nerd, a newbie to this side of science, this is the article for you. In this, I’ll explain what Quasars and Pulsars are, some of their similarities, and some differences. I’ll even show some jaw-dropping photos of particularly special quasars and pulsars. All in all, you’ll get a beginner’s guide to telling these two celestial bodies apart. 

Quasars are a type of active galactic nuclei, or AGNs. These are galactic cores formed by dust and debris going into a supermassive black hole, and they emit electromagnetic radiation. Their bright light, caused by gravitational and frictional forces, and distance from Earth separate them from other AGNs. The Hubble telescope found the brightest Quasar in 2019, after scientists searched extensively with gravitational lensing. Below is a picture of the telescope’s findings. 

Pulsars are a type of neutron star, which are formed when stars collapse. They rotate and emit radiation at intervals. They have intense magnetic fields that move streams of particles to create light. These streams of particles are called jets. Because the magnetic field is most often not aligned with the axis of the pulsars, their light can only be seen when it is pointed towards us. 

One important similarity of the two is that they both emit radiation. Quasars emit radio waves and X-rays, while Pulsars emit X-rays and gamma radiation. Moreover, they both emit light, although pulsars pulse and quasars do not. They also look very similar, but that is where the likenesses end. There aren’t many more similarities, but there are plenty of differences. 

One very glaring difference is what they are. Pulsars are stars, or rather, collapsed stars. Meanwhile, Quasars are cores of galaxies, or black holes with debris. This also means that they have vastly different sizes and luminosities. Quasars tend to be bigger and brighter. Furthermore, Pulsars are much closer to Earth compared to quasars. The nearest pulsar is 391 light years away, while the nearest quasar is more than 581 million light years. 

Quasars and pulsars and both extremely interesting astronomical bodies. Quasars are supermassive black holes with dust and debris rotating around them, while pulsars are collapsed stars that emit light and radiation. They do have some similarities, like how they look, but certainly have more differences. But either way, there are truly interesting things to study, and a sight to behold.

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