Eagle Ray Nebula · SH 2-63 -- Reflection not Emission Nebula

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Although SH 2-63 was originally cataloged in 1959 as an emission nebula, is has virtually no Ha and is actually a reflection nebula.

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Sh 2-63 is primarily a reflection nebula / illuminated molecular cloud (dust), rather than an emission nebula.

While Stewart Sharpless cataloged it in 1959 under the assumption that it was an H II (emission) region—like the rest of the Sharpless catalog—modern imaging and spectroscopy have shown that it is not an ionized H II region:

  • Composition: Sh 2-63 (also cataloged as LBN 86, and associated with high-latitude molecular clouds MBM 158 / MBM 159) consists almost entirely of interstellar dust and molecular gas.

  • Filter Response: It has virtually no detectable $H\alpha$ emission. Narrowband dual-band or $H\alpha$ filters will show little to no signal.

  • Imaging Strategy: Because it shines via scattered starlight (reflection and faint galactic cirrus/IFN-like dust), it is best shot using broadband LRGB under dark skies rather than narrowband filters.

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Thanks for this.

Telescopius trusts a lot in SIMBAD info (which is populated by thousands of amateur and professional astronomers around the world), and for this entry the only type they have is actually HII.

Thanks for reporting this inconsistency. I guess I’ll have to add some manual overrides for this and many other small fixes.

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Yep seems to be quite a controversy about it, which appeals to me, but i get it.