Hemisphere:  Northern  ·  Constellation: Cygnus (Cyg)
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Te J2102.1+4710 in Cygnus, 


            Mark Stiles
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Te J2102.1+4710 in Cygnus

Getting plate-solving status, please wait...
Te J2102.1+4710 in Cygnus, 


            Mark Stiles
Powered byPixInsight

Te J2102.1+4710 in Cygnus

Technical card

Imaging telescopes or lenses: Skywatcher MN190

Imaging cameras: QSI6120wsg5

Mounts: Orion Atlas Pro AZ/EQ-G Atlas Pro az/eq-g

Guiding telescopes or lenses: Skywatcher MN190

Guiding cameras: ZWO ASI120MM-S

Software: SGPRO, PHD2. PixInsight

Filters: Astrodon E-series 2 R  ·  Astrodon E-Series 2 3nm OIII  ·  Astrodon E-Series 2 5nm HA  ·  Astrodon E-series 2 G  ·  Astrodon E-series 2 B

Dates:Aug. 14, 2020

Astrodon E-Series 2 3nm OIII: 209x900" (52h 15')
Astrodon E-Series 2 5nm HA: 152x900" (38h)
Astrodon E-series 2 B: 30x180" (1h 30')
Astrodon E-series 2 G: 27x180" (1h 21')
Astrodon E-series 2 R: 30x180" (1h 30')

Integration: 94h 36'

Avg. Moon age: 24.74 days

Avg. Moon phase: 23.77%

Astrometry.net job: 3803832

RA center: 21h 2' 6"

DEC center: +47° 9' 58"

Pixel scale: 0.640 arcsec/pixel

Orientation: 2.210 degrees

Field radius: 0.421 degrees

Resolution: 2514x4016

Locations: Back Yard, Dadeville, Missouri, United States

Data source: Backyard


Te J2102.1+4710 is an exotic nebula that is one of a few nova shells identified around a cataclysmic variable system. It was discovered by the Deep Sky Hunters member Philipp Teutsch in 2006 and then later rediscovered in the IPHAS survey and is also catalogued as IPHASX J210205+471015. Initially it was classed as a nebula of unknown nature and also considered to be a possible planetary nebula.

Whilst attempting to confirm Te J2102.1+4710 as a true planetary nebula, spectra and images taken by professional astronomers showed it to be similar to another nova shell around the dwarf nova AT Cancri. The structure of the nebula is a nitrogen rich arc-like feature with an oxygen rich bowshock to the left. This is an indicator of it interacting with the surrounding interstellar medium as it moves through space. The cataclysmic variable is the star immediately to the right of the centre of the arc-like ring.

Images taken with a professional observatory show the arc to consist of multiple knots with a cometary morphology with 'tails' pointing away from the central star. In comparison, the structure of the bowshock is more smooth and diffuse. In addition to this, there is a second bowshock type structure along the direction of the [OIII] bowshock.

The formation of this nebula is explained by an outburst event of the cataclysmic variable with some of the ejecta sweeping up the surrounding gas in the ISM. The nebula contains enrichment of nitrogen and oxygen. According to chemical analysis of abundances of the gas, the arc-like ring is comprised of ejecta material. In contrast, the [OIII] bowshock is material from the ISM being swept up. Another sign of its interaction with the ISM is the deceleration of the expansion of the ejecta.

By studying its expansion parameters, both the distance and age can be ascertained. The distance has been calculated at approximately 2000 light years while it has a young age of 130-170 years implying that the nova outburst event that produced the nova shell took place sometime between 1850 and 1890. The expansion speed of the gas is 285 km/s and was calculated after comparing two sets of images taken a few years apart. Interestingly, the nova outburst seemed to have been missed by 19th century observers!

Description by Sakib Rasool

this was "first light" for me with the qsi6120.. some guy named Josh Smith was selling his, so i scooped it up :) thanks Josh! maybe someday i'll be able to do it justice


thanks to Dana Patchick for pointing out that Philipp Teutsch is the true discoverer of this nova