About Kevin

Cadsas webmaster

Primary and Secondary Mirrors Resilvered

I am pleased to report that the Alan Young Telescope at Cranbrook School, is now again in working condition.

Both mirrors of this large reflecting telescope, primary and secondary mirrors, have been re-silvered by Orion Optics.

Here is a photo by Graham Caller,

Mirrors Re-Installed In The Alan Young Telescope

Mirrors Re-Installed In The Alan Young Telescope

Photo taken just after the mirrors were reinstalled after their recoat by Orion Optics.

Bubble Nebula NGC7635

GCaller_bubble - OSH-1

Another fantastic astro image by CADSAS member Graham Caller.  this is NGC7635, the Bubble nebula in Cassiopeia.

He gathered data for this Oct 2016 to Jan 2017.  It’s a compilation of 35 single frames with exposure times of 5 minutes for Ha and 10 minutes for SII and OIII – total of 2 hr 55 mins of data capture.

OSH (OIII SII Ha) narrow band filters were used. He has colour mapped them to the RGB channels to give this false colour representation, in order to show a better contrast between the different channels.

OIII (oxygen) – red

SII (sulphur) – green

Ha (hydrogen) – blue

Resilvering The BIG Mirror

This morning, Rod and Ted of the CADSAS committee dismantled parts of the Alan Young telescope to remove the big 22.5″ primary mirror and the smaller secondary mirror.

The mirrors will be sent to Orion Optics very soon.

Orion will re-coat both mirrors.  We are hopeful their service will greatly improve the mirrors’ reflectance of light and therefore our imaging results.

Although often still referred to as “silvering”, the Orion recoating does not use silver. The modern and widely accepted Hilux coating, uses aluminium in the mirror coating process.

Come and visit in the Autumn when it’s dark again and see the results.

Contributing to the Citizen Science Project on Variable Stars

Over the last few months, CADSAS has been contributing to this Citizen Science project on variable stars.

We capture images of specific night sky objects, process those images using dark and flat frames and then send them to the project leader Dr Dirk Froebrich of the University of Kent.

The project is studying newly-formed, blue stars. Our target winter objects are currently NGC 2244, NGC2264 and NGC1333. We have submitted 8 images so far.

CADSAS are one of a small number of amateur contributers to this project.

Lunar Images From Our Recent Autumn Skywatch Public Meeting

We held an Autumn Skywatch on 10th October for our members and the general public who wanted to come along. The clouds did not look promising that afternoon, but cleared pretty well by 8pm.

Many of our telescopes were set up outside and a good range of astronomical targets were observed, guided by our more knowledgeable members.

Here are three images captured that night with our big telescope, the Alan Young. They have been reduced in resolution for the web.

Clvius and Tycho

Clavius and Tycho

Archimedes and Plato

Archimedes and Plato

Monte Apenninus and Caucasus

Monte Apenninus and Caucasus