M42 Imaged by Chris Thayer

The Orion Nebula, M42 (also designated NGC 1976) is a diffuse nebula (an HII region) situated south of Orion’s Belt and is one of the brightest nebulae, and is visible to the naked eye.   It is approximately1,344±20 light years away and is the closest region of massive star formation to Earth.  It is estimated to be 24 light years across.  The nebula surrounds and is excited by the four young stars of the Trapezium.  The main part of the nebula is separated from a smaller part (known as M43) by a dark absorbing region called the Fish’s Mouth.

HII regions are interstellar gas clouds consiting of ionized hydrogen and are normally associated with regions of active star formation.  UV flux from hot young stars ionizes surrounding gas creating complex but beautiful nebulae such as M42.  In gasseous  galaxies, HII regions trace locations where vigorous starbust formation is taking place.

Lookup M42 on SEDS

M42 imaged by Chris Thayer - click to enlarge

This image was taken using an ED 80 and Mead DSI2c, and guided using a DSIc and LX200 GPS 10″ at f6.3.