SH2-261 - Lower's Nebula |
SH2-261 - Click on image to view larger image. Opens in a new window. |
| Stewart Sharpless added this object to his
catalog of emission nebulae in 1959, but it was discovered in
1939 by amateur astrophotographer Harold Lower and his son
Charles. For this reason it is also referred to as Lower's
Nebula. It lies within the borders of the Orion constellation
and is estimated to be about 3200 light-years away. This is
primarily an emission nebula and is rich in ionized hydrogen,
sulfur and oxygen. This nebula is sometimes referred to as the Big Brain Nebula due to its shape, but there are some who refer to it as the Eye of Ra, especially with that interesting Oiii "cavern" glowing like a blue lagoon surrounded by the deep yellow and orange/brown "walls". That Oiii region has been described in Astrobin image posts as a blue submarine, a blue rubber duck, and recently an Image of the Day on that site a close up of that region was creatively named "Monomakh's Cap". image in Astrobin. Link to Astrobin version. |
| Constellation: Lacerta |
| When Visible: June - November |
| Distance: 1,200 Light-years |
| Date: August 2026 |
| Location: Location: Starfront Observatories, Rockwood, Texas |
| Exposure Details:
Ha: 119 × 5 minutes SII: 86 × 5 minutes OIII: 73 × 5 minutes 23 hrs 10 minutes total exposure |
| Equipment Used: Takahashi FSQ-106N on a ZWO AM5N mount. ZWO ASI-2600MM Pro camera with 7 x 50mm filter wheel and Antlia Pro filters. Externally guided with a ZWO ASI224MC camera on a William Optics UniGuide 50 guide scope. |
| Acquisition Software : Nighttime Imaging 'N' Astronomy, PHD2 |
| Processing Software: MaximDL, PixInsight, Photoshop CS5, IrFanView |