Messier 109

Hi ASOD,

Please find hereby a recent sketch of the barred spiral galaxy M109 in Ursa Major, made during our astro-holiday in Northern France about a month ago. That night the sky completely cleared out with impressive SQM values around 21.6 – being amongst the highest possible in light-polluted Western Europe.

One of the objects scheduled to revisit was Messier 109, since it contains a complex barred spiral structure that is difficult to visually discern. Attentive averted vision under a dark sky though brings out these beautiful features!

Sketch details:

Location: 18 April 2015 – 23h54 UT – Grandpré (Fr)
Conditions: NELM 6.6 – SQM-L 21.6 – Seeing moderate
Optics: SCT C11 (279mm f/10) – Nagler 13mm (215x – FOV 23 arcm) – no filters
Media: graphite pencil on white paper, scanned & inverted using GIMP2

Notes:

Large diffuse face-on galaxy, displays a bright core containing a diagonal barred structure through a round, mottled glow. Attentive averted vision brings out a subtle theta-like structure, less intense at the eastern side and more pronounced on the northwest and southern outer side. The inside of the barred spiral, to the eastside of the core, appears more dark and contains a nice faint field star.

Additional observations of that night can be found in the deepsky database www.deepskylog.org

Clear nights !

Tom