NGC1909 (IC2118) LRGB  (North Left)   (~40% Downsized -> 1,320K Rotated)

*   *     Technical Data     *   *

Date	01-22 through 01-24-2009
Exposure	121hrs 50mins LRGB, L 3hrs, R 3hrs8mins, G 3hrs, B 3hrs42mins.
Optics	1995 AP155EDFS #95, f:7.26, FL=1126
Mount	2007 AP1200 GTOCP3 #714
Camera	2005 SBIG STL-11000M, 1.65 arc.sec p/pixel @ -20C, AstroDon I-Series HaRGB.
Guider	2006 SBIG STL-Remote w/Red filter, TAK FS-102, FL-816mm f:8, 1.87arc.sec p/pixel.
Equipment	AP Field Flatener, FeatherTouch FTF-3545 & Digital MicroFocuser, PreciseParts Adapters. Custom built Water Cooling and DryAir Purge Systems
Processing	MaximDL/CCD w/Russ Croman's Sigma Combine Plug-In, PhotoshopCS2,  FITSplug by Eddie Trimarchi, AstroActions by Noel Carboni
Location	StarFields Observatory (SFO), Chiefland Astronomy Village, Florida,   29d 24m 26.34s  North,   82h 51m 31.26s   West
Comments	... Surprised to find Emission nebula. Rersearch reveals the emission is caused by T Tauri stars imbedded in IC2118. See below. ... Over 20 background Gx's.

Discussion of T Tauir stars and location image from: http://www.aanda.org/index.php?option=article&access=bibcode&bibcode=2004A%2526A...418...89KFUL We identified new pre-main sequence stars in the region of high-latitude molecular clouds associated with the reflection nebula IC 2118, around and . The stars were selected as T Tauri candidates in objective prism plates obtained with the Schmidt telescope of Konkoly Observatory. Results of spectroscopic follow-up observations, carried out with the FLAIR spectrograph installed on the UK Schmidt and with ALFOSC on Nordic Optical Telescope, are presented in this paper. Based on spectral types, presence of emission lines and lithium absorption line, we identified five classical T Tauri stars and a candidate weak-line T Tauri star projected on the molecular clouds, as well as two candidate pre-main sequence stars outside the nebulous region. Using the near infrared magnitudes obtained from the 2MASS All Sky Catalog (IPAC 2003) we determined the masses and ages of these stars. We found that the five classical T Tauri stars projected on the clouds are physically related to them, whereas the other stars are probably background objects. Adopting a distance of 210 pc for IC 2118 (Kun et al. 2001) and using Palla & Stahler's (1999) evolutionary tracks we derived an average age of yrs and a mass interval of 0.4-1.0 for the members of the IC 2118 association.

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