Thursday, April 20, 2017

M101 - The Pinwheel Galaxy

Messier 101 - The Pinwheel Galaxy (a.k.a. NGC 5457) is a face-on spiral galaxy distanced 21 million light-years away from earth in the constellation Ursa Major.  M101 is a large galaxy comparable in size to the Milky Way with a diameter of 170,000 light-years.  The galaxy is asymmetrical due to the tidal forces from interactions with its companion galaxies. These gravitational interactions compress interstellar hydrogen gas, which then triggers strong star formation activity in M101's spiral arms that can be detected in ultraviolet images.  On August 24, 2011, a Type Ia supernova, SN 2011fe, was discovered in M101. The supernova was visual magnitude 17.2 at discovery and reached magnitude 9.9 at its peak. (source: wikipedia).

I was lucky lucky to get this last Saturday when the sky unexpectedly cleared up enough to get 1.5 hrs of decent exposures.  I think I can do better with this object with more exposures, however, that will have to wait as I have too many other thing to capture on limited clear nights in the Northeast.  The weather has been awful since Saturday and it does not seem to be getting any better anytime soon.  I used the Synthetic Flat-Layer removal method described by Trevor Jones from AstroBackyard to cleanup the gradients this time as it produced the best results.

BTW this object number 70 on my Messier catalog.  Enjoy.


Wide Field

M101 - The Pinwheel Galaxy
Location: Happy Frog Observatory, Monroe, CT
Date: 4-15-17
Camera: Canon EOS Rebel T3i(a), Backyard EOS
Telescope: Orion ED80 80mm
f/7.5 Apochromatic Refractor Telescope
Barlow: None
Focal Length: 600mm
Focal Reducer: Orion 0.8x Focal Reducer for Refractor Telescopes
Mount: Orion Sirius EQ-G GoTo Telescope Mount
Filter: Astrodon UV/IR
Autoguiding: QHY-5L-II-M attached to an Agena 50mm Guide Scope with Helical Focuser
Exposure: 59 x 90s
ISO: 1600
Temp: 7 C
Post Processing: Deep Sky Stacker, Photoshop, Lightroom, Gradient Exterminator, Astronomy Tools, StarTools.

No comments:

Post a Comment