Image Details
About This Site
Image Gallery
Click for full screen image

Dates & Location

29th April - 11th May 2019 from the ICAstro site, Oria, Spain. Elevation 1022 m
Lat 38°:45.4 N, Long 00°:02.1W


Catalogue Identification(s)

M 101
NGC 5457

The Pinwheel galaxy

In this image, North is up

Equipment Used

AstroPhysics AP155 mm focal length, F7.1
Paramount ME German equatorial Mount.
Camera - SBIG STT-8300FWG with internal 7 position FW and OAG
TheSkyX Pro telescope control.
SGP used for camera, PHD Guide and Focus control.

Lakeside Focuser S/W on AP rack-and pinion drawtube



Where it is in space

This field is approx 116 x 88 arcminutes - ie ~ 4 x 3 Moon diameters
M 101 lies approx 5.5 degrees NNW ofeta UMa, the last bright star at the tail of the Great Bear

The galaxy is approx 21 million light years away and spans about 170,000 light years i.e. about 1.7 x the size of our Milky Way galaxy


Remote sessions using Splashtop control from Ravenshead, UK
Exposures: L:18  x 20 min + R:G:B 12 x 10 min each
Narrowband exposures: Ha 22 x 20 min

All sub-exposures
-20°C. All images binned 1x1.
Automated remote sessions using Sequence Generator Pro (SGP)


  What it is

The Pinwheel Galaxy is a face-on spiral galaxy discovered by Pierre Méchain on March 27, 1781. It was communicated to Charles Messier who verified its position for inclusion in the Messier Catalogue as one of its final entries = 101


Processing Methods

All data reduction with CCDStack. Lum, RGB masters and RGB colour combine prepared in CCDStack
Master Ha image created in PSCS6
Master (Lum+RGB) colour created in PhotoShop CS6.
Master Ha and master LRGB image combined inPS CS6. Colour balancing and finishing
in PS CS6