NEW DISCOVERY: Strottner-Drechsler 153 / Ingrid's Mist

StDr 153 is a new candidate planetary nebula in the constellation Serpens.

It was discovered by my friend and colleague Xavier Strottner and me in August 2021 and, after acceptance by Pascal le Dû, was cataloged as StDr 153 / PNG 014.6+00.7.

This photo, taken in collaboration with our friends Peter Goodhew and Sven Eklund, is the first image of this faint object ever.

Image processing was done by Marcel.

Please excuse the slightly blurry image—this is due to the object's small size and the need for a very long focal length. ☺️ Typical of planetary nebulae is a compact shell of H-alpha and OIII stars surrounding a small white dwarf.

The central star is exceptionally blue, suggesting a temperature of 30,000 K or higher.

Precise distance determination was not possible due to insufficient GAIA and TESS data.

In the near future, a spectrum (a chemical fingerprint) of StDr 153 will be created, which will hopefully confirm that StDr 153 is a true planetary nebula.

Those with a trained and keen eye will discover another potential planetary nebula in the upper right of the image, discovered by Xavier Strottner and our friend Lionel Mulato, cataloged as StMul1. StMul1 was recently examined using a spectrum and classified as a potential planetary nebula.


In the near future, a spectrum analysis will be performed, which will hopefully confirm that StDr 153 is a true planetary nebula. *
Coordinates: 18:14:26.86 -15:53:28.53
Constellation: Serpens
Size: 2.5 arc minutes
*
Frames:
Astrodon 3 nm narrowband OIII: 106x900" (26h 30') am 1x1
Astrodon 5 nm narrowband H-alpha: 36x900" (9h) am 1x1
Astrodon Gen1 E-Series Tru-Balance Blue: 27x300" (2h 15') am 1x1
Astrodon Gen1 E-Series Tru-Balance Green: 28x300" (2h 20') am 1x1
Astrodon Gen1 E-Series Tru-Balance Red: 30x300" (2h 30') am 1x1
Chroma H-alpha 3nm Bandpass: 39x300" (3h 15') bin 2x2
Chroma OIII 3nm Bandpass: 244x300" (20h 20') bin 2x2
Recording time: 66h 10'