NGC1499 - California Nebula

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NGC1499 - California Nebula in H-Alpha

Many of the nebula's give off a unique specturm of light called H-Alpha that is the result of ionized hydrogen gas.  Bassically a hydrogen atom that has been stripped of an electron.  A nearby star is needed to excite the gas so that it glows red.  This photo is done with a filter that only allows transmission of the H-Alpha spectrum.  It is black and white because there are no color components to the image.  The H-Alpha is a narrow band that allows more detail to emerge than what you might see with a combination of red/green/blue (RGB).  The downside to using H-Alpha filters is that the exposure have to be much longer.  This picture was exposed for a total of 2 hours and 20 mintues.

The nebula itself if very large and faint.  It takes up more that five times the diameter of the moon in the sky.  Because it is so dim, you cannot see it very well optically.  It is believed that the star at the top of the picture is probabily energizing the nebula so that it glows.

Date:  01-20-05

Telescope: Nikon 300mm (4.5) lense piggy backed on mount.      Camera:ST10ME  

Mount: Astrophysics 900 Goto

Exposure Time: H-Alpha 220minutes 1x1 bin

Processing: Maxim DL, Adobe curves, selective sharpening