11 of 12 photos
IC 1318a, LBN 239, Cygnus

IC 1318a, LBN 239, Cygnus

530 mm f/5 15.3 hours, July 2012, Photograph

IC 1318a, LBN 239, 241 and 243 — The HII regions IC 1318a, LBN 239, 241 and 243 are components of Cygnus-X, one of the richest known regions of star formation in the Galaxy. Cygnus-X contains many HII regions, a number of Wolf-Rayet and O3 stars and several OB associations. Cygnus-X also contains one of the most massive molecular complexes of the nearby Galaxy with a total mass of ~3 million Msolar and a diameter of 200 pc. IC 1318a adopted distance 1.5 kpc. From Reipurth et al., "Star Formation and Young Clusters in Cygnus", Handbook of Star Forming Regions, Volume I: The Northern Sky, Astronomical Society of the Pacific Monograph Publications, Monograph 4, Edited by Bo Reipurth, p. 36-89, 2008.

Cr 419 and HD 193322 — The young open cluster Collinder (Cr) 419 surrounds the multiple star system HD 193322 that contains at least four components classed as O8.5III, B1V, O9Vnn and B1.5V. HD 193322 has a simplex hierarchical structure with successive orbital periods of 0.9 yr (O8.5III and B1V), 35 yr (O9Vnn) and 21 kyr (B1.5V). O8.5III and B1V pair mass 43 +/- 7 Msolar, O9Vnn star mass ~15 Msolar, cluster distance 741 +/- 36 pc. From Roberts et al., "The membership and distance of the open cluster Collinder 419", The Astronomical Journal, 140:744-752, 2010 September, and Gries et al., "Combined Spectroscopic and Interferometric Orbits for HD 193322", Bulletin de la Société Royale des Sciences de Liège, 80:678-682, 2011.

IC 1311 — The old open cluster IC 1311 is projected in Cygnus but lies well beyond the Cygnus-X region. The cluster is located at a distance of 8 kpc from the Galactic center and 0.4 kpc above the Galactic plane. Metallicity [FE/H] -0.30, heliocentric radial velocity -63 km/s, heliocentric distance 6.6 kpc, age 1.1 Gyr. From Warren et al., "Metallicities and radial velocities of five open clusters including a new candidate member of the Monoceros stream", Monthly Notices of the Royal Astronomical Society, 393: 272–296, 2009.

WR 138a — The Wolf-Rayet star WR 138a and its circumstellar nebula were discovered serendipitously from Spitzer Space Telescope archival data. The star belongs to the WN8-9h subtype, has a temperature of 40,000 K and a wind composition dominated by helium with 20 percent hydrogen. The circumstellar nebula, visible in the Spitzer 24 μm IR image, has a ring-like structure with a diamter of ~2.3 arcmin. Proper motion measurements indicate that WR 138a is a runaway star with a peculiar (transverse) velocity of ~50 km/s. Luminosity 200,000 Lsolar, distance 4.2 kpc. From Gvaramadze et al., "Discovery of a new Wolf-Rayet star and its ring nebula in Cygnus", Monthly Notices of the Royal Astronomical Society, 400(1):524-530, 2009 September.

Coordinates: RA 20h 14.9m, Dec +41° 26’, PA -0° 4’
Field of view: 1° 56’ x 1° 28’
Image scale: 4.2” / pixel

Date: July 2012
Location: Cascade Range, California
Exposure: 23 x 40 minutes (15.3 hours), binned 2 x 2 at -20° C

Guiding error: 0.7" rms
Star FWHM: 4.6", histogram
Star eccentricity: 0.33
Camera noise: 14 e- rms
Background noise: 29 e- rms
Subframe location: 709 e-
Subframe scale: 256 e-

Telescope: Takahashi FSQ-106EDX 530 mm f/5
Camera: Quantum Scientific Imaging 683wsg
Filter: Astrodon H-alpha, 3 nm bandwidth
Focuser: Spike-a Bahtinov Mask
Guider: Santa Barbara Instrument Group ST-i
Flats: Alnitak Astrosystems Flat-Man
USB: Icron Ranger 2122, Moxa UPort 404
Mount: Takahashi EM-400 Temma2M
Acquisition: Diffraction Limited MaxIm DL, CCDAstro Temma, ASCOM Platform
Processing: Pleiades Astrophoto PixInsight, MathWorks MATLAB, IHRP Platform