[an error occurred while processing this directive]
Calvin Observatory
Weather Forecast
Cool Images
Observing Request
External Links
Related Links
Wildrik Botjes Planetarium
Physics & Astronomy Department

Astr110 Photography Projects, Fall 2006

Previous imageUp to Astr110 IndexNext image

Blue Reflection Nebula in Orion (NGC 1977), Jessica Buntin

Blue Reflection Nebula

NGC 1977, a nebula within the Orion constellation below Orion’s belt, lights up the surrounding sky with scintils of blue light. A nebula, from the Latin term meaning “cloud” or “mist,” used to indicate any object in the night sky outside of planets and comets, but today the definition has narrowed to usually mean gas and dust clouds. Reflection nebulae in particular, including NGC 1977, are clouds of dust that reflect the light of nearby stars.

            This nebula in particular, roughly 1500 light years from Earth, is blue in color because the nebula’s dust scatters blue light more efficiently than red. The three stars pictured are surrounded by dust clouds before and behind them relative to the viewer, the clouds behind reflecting the blue light while the clouds before block it, creating the appearance of intruding lines of darkness. The photo size is 14 by 21 arcminutes, and the nebula’s linear size is 3.054 light years, found by using the small angle formula (this is only the size of the objects pictured, not of the entire Orion constellation).

David Malin http://antwrp.gsfc.nasa.gov/apod/ap010722.html


Right Ascension (J2000) 05:35:14.5
Declination (J2000)


Filters used blue(B), green(V), red(R)
Exposure time per filter

B 10 images for 60 secs

V 5 images for 60 secs

R 5 images for 60 secs

Date observed

October 20 BVR