Craig Cortis'

Observing Extreme Astrophysical Objects

Seeking Markarian 421: The Brightest Blazar

March 2011 : By Craig Cortis

An easy star hop leads to a BL Lacertae-type active galaxy in Ursa Major that is visible in 8-inch and larger backyard telescopes.

Can You Find a Quasar? (You Might be Surprised)

May 2010 : By Craig Cortis

Readers having 8” or larger telescopes might wish to observe a quasar, provided you can follow a detailed finder chart and manage to isolate a 12.8 magnitude object that looks exactly like a star, but actually is not. Rather it’s the brightest known quasar and, at a distance of 2.5 billion light years, will be by far and away the most distant thing in the universe most of you will ever see in your lives.

Cygnus X-1: A Black Hole You Can Find!

September 2009 : By Craig Cortis

Unusual celestial objects having bizarre or extreme astrophysical properties often make highly desirable observing targets for amateur astronomers wishing to find things outside the scope of the usual, customary star party “menu”. So how do you find something that even the Hubble Space Telescope can’t image in visible light? The answer is surprisingly simple and is my topic for this month.

A White Dwarf You can Actually See!

February 2009 : By Craig Cortis

A double star in Eridanus contains a white dwarf star that is easy to locate and see with small telescopes.