Trifid Nebula

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Table Mountain, Ellensburg WA
21 July 2001
Takahashi CN212 at f/4, Losmandy GM-8 mount,
tracking by ST-4 autoguider on guidescope
Superposition of 20- and 30-minute exposures on LE400 film

M20, The Trifid Nebula

This has been one of my summer goals, a picture of the Trifid Nebula. I like this because it shows contrasting colors from the two different ways that we see the large clouds of gas and dust we call nebulas. The strong red color is from emission of energized hydrogen (the gas itself is glowing). The blue is the color when a nearby bright star shines onto the gas and dust in the cloud. Like the sky, it scatters blue light.

M20 is visible only in the summer. At my lattitude, it is quite low on the horizon, and there's only a few hours of darkness in the short summer night to take the picture.

This picture was taken during my Nightscape Odyssey.