From 2016 - Len Adam - My NGC 2346 region "Shallow Field" in Monoceros

A 10 minute exposure from Siding Spring taken in 2016 remotely from the UK.

"NGC 2346 is a planetary nebula near the celestial equator in the constellation Monoceros. It is bright and conspicuous and has been extensively studied. Among its most remarkable characteristics is its unusually cool central star, which is a spectroscopic binary, and its unusual shape. The binary star, which has a period of about 16 days, is also variable, probably due to dust in orbit around it. The dust itself is heated by the central star and so NGC 2346 is unusually bright in the infrared part of the spectrum. When one of the two stars evolved into a red giant, it engulfed its companion, which stripped away a ring of material from the larger star's atmosphere. When the red giant's core was exposed, a fast stellar wind inflated two ‘bubbles’ from either side of the ring." Wikipedia

The un-annotated image

Messier 13 Globular cluster in Hercules

Surely M13 has to be one of the most spectacular globular clusters on Messier’s List. With an approximate diameter of 20 minutes of arc it appears as a massive ball of stars. M13 had originally been discovered in 1714 by Edmund Halley of Halley’s Comet fame, but was catalogued by Messier 50 years later on June 1^st 1764.

Messier commented about M13:  “Nebula without star, discovered in the belt of Hercules; it is round & brilliant, the center [is] more brilliant than the edges, one perceives it with a telescope of one foot; it is near two stars, the one & the other of 8th magnitude, the one above and the other below it: the nebula ['s position] was determined by comparing it with Epsilon Herculis.” (SEDS).  M13 can be visible to the naked eye in dark skies as pointed out by Halley himself.  Reverend Webb regarded it as being “ spangled with glittering points in a 5 ½ foot achromat, becoming a superb object in large telescopes”. 

Messier 13 lies at a distance of 25,100 Light Years from us. (SEDS) This is roughly one quarter of the distance of the major axis of our Galaxy. The negative image shows foreground star Tycho 2588:1662, which has a magnitude of 10.99 and lies at a distance of only 72 Light Years. The cluster members appear fainter than this star in the region of 12^th magnitude. There have been many calculations over the years as to the number of stars in this globular cluster  - perhaps you could try your own estimate from the photograph! The cluster subtends an angle of 20 minutes of arc at a distance of 25,100 Light Years. My rough calculations based on these figures give an approximate diameter of about 150 Light Years.

The Dumbbell Nebula

The Dumbbell Nebula Messier 27

Barnard's Star

Barnard's Star

The Andromeda Galaxy Messier 31 imaged with Redcat/Canon 40D

The sub-exposures on this image total approximately 20 minutes. The Redcat 51 and the Canon 40D were mounted side by side with my Ritchey-Chretien 8 inch telescope and 90mm Skywatcher guidescope. The guidescope uses a ZWO ASI 120MC camera and the 8-inch scope uses a ZWO ASI 1600 Pro Cooled camera. The M31 galaxy will not fit into the field of view of the 8-inch scope but fits nicely into the FOV of the Canon 40D/Redcat combination.

nation.

Finally setting up in Spain again!

After a couple of months back in the UK I am finally able to start some practical astronomy in sunny Andalucia. The temperature is over 30 degrees C every day - just the way i like it. I have purchased a William Optics Redcat 51 lens to get some wide angle images at f/4.9 250  mm focal length. I want to use this in the UK as part of my portable set up with a Canon 40D camera so over the last few days I have put this together with my Skywatcher Star Adventurer setup that I describe below. First of all this is what the setup looks like.

The system is self sufficient in that the rechargeable battery pack mounted on a 'cold' shoe on top of the Canon 40D provides power for the camera and the mount, enabling an entire night of imaging without recharging. I have tested the battery pack on the mount alone and it was still driving after 24 hours. This means that there are no internal batteries on the mount and no need to replace the camera battery. A dummy camera battery is supplied from the external battery pack. 

The image above shows the battery pack. On the left the 'USB OUT' output at 5 Volts goes to the mini USB power input to the Star Adventurer mount. The 'DC9VOUT' output goes to the dummy battery in the Canon 40D. Note that the output voltage of 9V is slightly higher than the rated voltage inut for the camera power from a normal Canon battery. I read up on this when I first set this up and risked it followig the experience of others.  

M101 and Alkaid

I used my Canon 40D and a 75mm lens to take this 30 second image showing the position of M101 in relation to the star Alkaid in the Big Dipper.

Imaging the Messier Objects Sample Page

Here is a sample page from my book "Imaging the Messier Objects Remotely from your Laptop." Available from Amazon. https://tinyurl.com/yyv7qy3c   

Paperback Price on this date: £19.79 Available on Amazon Prime

Kindle Price: £18.89

The Moon - 15th April 2019

I imaged the moon last night using a red filter. 1/1000th second. 8-inch RC + ZWO ASI 1600 MM Pro.

Occultation of M44 stars Tycho 1395:1993 and tycho 1395:2711 - animation

On Saturday 13th April 2019 the Moon moved across the Open Cluster Messier 44. The animation below shows the Moon  occulting two of the M44 stars as it moves from West to East. The exposure time for each image was 0.05 seconds or 1/20th second. The time each 0.05s exposure started is shown at the bottom of the screen.  There is roughly 7 seconds between each exposure. The two close stars pop out of view behind the Moon in sequential frames. An earlier (single) occultation is shown in the previous posting.