From the January 2022 issue

101 Must-See Cosmic Objects: NGC 1275

By | Published: April 15, 2022 | Last updated on August 25, 2023
NGC1275
Dan Crowson

NGC 1275, often referred to as Perseus A, is the brightest member of the Perseus galaxy cluster. It lies roughly 225 million light-years away and has a diameter of slightly more than 100,000 light-years. The A part of its designation means the object is a strong source of radio emission.

NGC 1275 is considered a Seyfert galaxy. Each member of this class of active galaxies has a brilliant quasarlike nucleus, but not so bright that it drowns out the rest of the galaxy.

In addition to being a strong radio source, NGC 1275 is also a strong emitter of X-rays. The source of this radiation is the center of the galaxy, where a supermassive black hole with a mass some 800 million times that of the Sun gorges itself on gas. The friction and other forces produced by the gas as it spirals into the black hole generate X-rays.

The Perseus galaxy cluster, also known as Abell 426, is part of the Pisces-Perseus Supercluster. This chain of galaxy clusters stretches more than 40° across the sky. To find the Perseus galaxy cluster, look 2° east of Algol (Beta [β] Persei). Through a large amateur telescope, several of its galaxies — all ellipticals — appear bright, small, and nearly circular. Don’t confuse NGC 1275 with NGC 1272, a similar galaxy just 5′ to the west. NGC 1272 is ever-so-slightly brighter.

Through a 10-inch telescope, you’ll spot a dozen galaxies in a field of view 1° across. Most lie south and west of NGC 1275. Here’s a region of sky where increased aperture really pays off. As you look through larger telescopes, you’ll see more galaxies, and the ones you’ve already spotted will show a bit more detail — as much as ellipticals can show, anyway.


Make sure to explore Astronomy’s full list of 101 cosmic objects you must see. New entries will be added each week throughout 2022.