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| Date: | 26.10.1995 | Time: | 20:30 UT | Exposure: | B:15m, V:10m, H-alpha:10m, I:10m |
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| Field of View: | 13.2' x 16.0' | Receiver: | WWFPP, 20482 CCD | Filter: | B, V, (H-alpha, I) |
| Instrument: | 1.23m | Observatory: | Calar Alto | Observer: | T. Credner & S. Kohle |
Astronomical Institutes of the University of Bonn
This three color composite is consisting of I, H-alpha, Johnson V, and B filter exposures, represented in red (I + H-alpha), green, and blue respectively.
This nebula was ejected approximately 3000 years ago by the old blueish central star, which can be seen in the very center of M 27. The gas is emitting light predominantly in special emission lines, e.g. the green O[III] line and the red H-alpha line. The energy for this gas emission is given by the high energetic radiation of the central star. If you zoom in to the above image (click it!), you can clearly see the blue color of this star, indicating its high surface temperature of about 85000 K.