NGC 4236 is an apparantly large, barred spiral
galaxy in Draco of low surface brightness, seen at an oblique angle not far from
edge-on. It measures 22.9 x 7.2 arcminutes in the sky. NGC 4236 is probably a
member of the M81 group of galaxies. Its distance amounts to 11.7 million light
years. The central bar of this galaxy is well defined, and the spiral arms
contain many "knots" consisting of huge star clusters with ongoing star
formation.
Lots of small background galaxies can be found within this image if you look
closely.
Exposure Data
- Instrument: 9.5" f/4.9 Newtonian
- F/stop: 5.6
- Exposure: 14 x 10 minutes + 2 minutes
- Camera: ALccd 6c Pro = QHY8pro
- Offset/Gain/Temp: 111 / 51% / -20°C
- Date: April 8, 2010
- Exposure start: 21:31 MESZ
- Location: Steyersberger Schwaig, Lower Austria
- Conditions: Visual limiting magnitude 6.3 mag, seeing 1.8-3.0" FWHM, temperature 0°C, slight wind, low humidity
- Autoguider: Meade Pictor 216 XT, max. error: 3" (RA) / 2" (Dec)
- Enhancement: Basic data reduction, combine, logarithmic curves, crop, background flattening, color correction, noise filtering, local contrast enhancement, star size reduction, dynamic range extension
- Remarks: Fine new observation site. Read an Observation Report
about the night (in German).
