Here is my personal collection of fun stuff which fellow astro-nuts may find interesting.
Please notify me if any of the links fail ( stuff gets taken down from the net all the time) and I will remove them.
                                                                           David Billington ( aka the BOSS )

Content :
  • The PHASES of the MOON Explained at last !
  • Just what is a Dobsonian telescope (and who is John Dobson)  ?
  • Hubble Ultra deep field in HD and 3D
  • Video clip of the EPOXI mission flyby of comet Hartley2
  • How some of the galaxies and nebula got their common names
  • Some concepts of SCALE for astronomers
  • Fight the Light ( join the campaign for Dark Skies)
  • Amazing Astro Photography WITHOUT a telescope !
  • Stellarium - the best planetarium and target identification system for your PC/Mac, EVER  --- and it's FREE !
  • The Aurora sky station -- see the Northern Lights (almost) live .
  • AMAZING video of the Northern Lights from the ISS orbiting over the USA .
  • The boss's Europa  image makes The Universe Today front page !!


and -  THE LATEST ASTRONOMY RELATED NEWS and images FROM ALL OVER THE WEB, updated every day


The PHASES of the MOON Explained at last !
It took me ages to understand how the phases of the moon occur, and I am often asked by non-astronomers what is going on when the moon changes it's appearance very night, and rises and sets at different times,  etc.
This is one night sky event you can see from anywhere, even a big city, and it deserves to be properly explained.
The animation below is an AWESOME explanation of the phases of the moon etc.
Just hit the "start animation" button in the bottom left hand box when the page has loaded, then you can tinker with the settings, speed etc.
Just what is a Dobsonian telescope ? ( and who is John Dobson ? ) 
What we call Dobsonian telescopes are of course really Newtonian reflecting telescopes, on a mount pioneered by a certain penniless monk John Dobson in the USA.
Isaac Newton "invented" the Newtonian telescope which bears his name and built the first working example in 1668.
The idea of a reflecting telescope was not altogether new, It was a Scottish astronomer, James Gregory (1638-1675) who published the first known design for a reflecting telescope in his book Optica Promota of 1663 but old Isaac  "reduced it to practice" ie actually built one that worked rather than just pontificated that such a thing should be possible. 
Isaac was a real character well worth reading about, if you get the chance .
Experiments and a passion for building stuff coupled with a fantastic mind led him to investigate everything from alchemy to spectroscopy and  the shape of the lens in the human eye ( by distorting the shape of his own eye using needles inserted round his eyeball and recording the results on his vision ! !).
The Newtonian reflector uses a curved mirror to gather light which avoids lots of the serious problems which lens based telescopes suffer from, once they get bigger than about 6-12 inches aperture, ie problems of chromatic aberration, and the enormous focal lengths needed to avoid this ( leading to the famous 40 foot and over telescopes !) , etc. A 30 inch lens based  telescope needed to be 40 feet focal length and the largest ever was a 50 inch  built for the Paris exposition of 1900 , which had a focal length of 187 feet !.
A list of big lens examples is here
Not exactly practical for astronomy ! !
Newtonians of very large aperture are however much more feasible, like the 100inch  here and 200inch telescopes here built in the early part of the 20th century in the USA. 
The history of the building of these huge monsters is a story in itself, and well worth reading  .
But I digress.........................
A good description of the Newtonian telescope and it's history is in Wikipedia here
On to our hero, John Dobson ..................
John Dobson, an astronomy obsessed monk who built his own telescopes and mounts from scrap materials ( in secret as the monastery leaders disapproved !) invented the Dobsonian Mount in the USA. Basically he had literally no money, but badly wanted a bigish telescope so he built one from scratch . He then sneaked out of the monastery to use the telescopes and to show the wonders of the night sky to the public. He trundled his scopes around the neighbourhood showing the night sky to anyone he could find.
    A BIG Dobsonian                                                      John Dobson    
By "built his own"  I mean he ground his own lenses from the bottoms of discarded jugs, and ground mirror blanks from old portholes ! ! The original Dobsonian mounts were made from free scrap wood, and carpet etc which  he salvaged from anywhere he could.
As you can see from the left hand photo, he was not afraid to think BIG aperture either ! John was once asked why he made such big telescopes , his reply ... " well if you can't sleep inside it at the end of a nights observing it is not a real telescope"
Eventually, after 23 years as a monk,  his absences from his monk's duties were so obvious that the monastery turned him out on the street for time wasting (!!) , and so, penniless and homeless, he  hitch-hiked to San Francisco where he set about popularising astronomy for the masses and set up the " San Francisco side walk astronomers", making more and more telescopes and providing these telescopes for the public to use freely on street corners on every clear evening.
Always a pioneer of recycling he built his 24" telescope in the early 70's for under $300 using mostly free materials.
Below John ( on the ladder) observing on a SF street corner through his " little one" telescope in 1989 ( image copyright Roger Ressmeyer )
John Dobson died in January 2014 at the ripe old age of 98 in the care of the monks at the monastery in California he had been a member of so many years before. A short biography can be read on the web site of the astronomy group he founded " the sidewalk astronomers" .
His biography makes amazing reading and is a real inspiration to anyone who thinks they are having  problems achieving their life goals, or that you need money to succeed ! ! !


Hubble Ultra deep field in HD and 3D
This is a great explanation of how the Hubble Ultra deep field came about and what it means. Watch , learn, and be humbled astronomer .

Hubble ultra deep field and 3D

Video clip of the EPOXI mission flyby of comet Hartley 2
This video clip of the EPOXI mission flyby of comet Hartley 2 is comprised of 40 frames taken from the spacecraft's Medium-Resolution Instrument during the encounter.
Space craft fly-by was at 12.3 Km per second and closest approach was about 700Km
A shame that the probe's high resolution camera failed earlier in the mission, but stunning images non the less.
Image credit: NASA/JPL-Caltech/UMD/Brown University

YouTube Video


You know, I often wondered how some of the galaxies and nebula got their, often romantic, common names.............
Then I came across the excellent images taken by a certain Mr Mark Sibole ,Fife Lake, MI  as publicity shots for Meade DSI imagers and telescopes, and many of these objects actually look like their names ! !
The Running Man Nebula - NGC1977 - by Mark Sibole
NGC 7635 The Bubble Nebula by Mark Sibole.
The Heart and Soul Nebula by Mark Sibole.
The Rosette Nebula by Mark Sibole.
Lots more examples of Mark's excellent images can be found at :

Some concepts of SCALE in the solar system and in the visible Universe as a whole. 
Jupiter and the Earth
For those who, like me, have been enjoying super views of Jupiter recently, here is a nice image giving the scale of this planet.
Jupiter, the Earth, the Moon and Jupiter's moon Io are here shown to the same scale. 
The Solar System
Now imagine the sun as a ball 8" in diameter, the size of a bowling ball, and imagine this bowling ball is in the centre of a cricket pitch....Got it in your mind ? 
Then to this scale the Earth is about 1/10 of an inch in diameter, the size of a small peppercorn and is 26 yards away from the Sun. The Moon, our furthest human exploration, is the size of a pin head, 2.5 inches from the peppercorn sized Earth.
Continuing outwards from the Sun Mars is another 14 yards away but you need to go another 95 yards before you reach Jupiter, ie over 135 yards from the sun now !
But out here is where the really big distances come in to play ..........
On from Jupiter another 112 yards before you reach Saturn, and from Saturn 249 yards to reach Uranus.
We are now almost 500 yards from the bowling ball sun, and it is essentially invisible to the naked eye.
But wait, what about Neptune you say ? Well, go on another 281 yards from Uranus to reach Neptune and then if you have the stamina, another 242 yards to get to Pluto.
So in the model Pluto is 1,019 yards from the 8 inch diameter sun, over half a mile
So mankind has voyaged 2.5 inches on this scale, and our robotic probes have voyaged over 1,000 yards (taking over 7 years at 50,000mph for the trip).
BUT on this scale model, our nearest stellar neighbour proxima is over 4,000 miles away, the distance from Munich to New York.
So much for visiting the stars............ 
OK the solar system  is BIG....and our nearest stallar neighbour is a long way off,  but how big is space, I mean everything......... the whole Universe really ?
The Visible Universe
As astronomers we think that we have some idea of the size of the Universe, at least we like to think so...........
This video narrated by Morgan Freeman is a superb explanation of the REAL size of the visible Universe.

Powers of ten

                                             Time to fight the light  ! ! !
Join the campaign for dark skies so all of the UK can enjoy the dark skies we have here in Cornwall.
The picture below says it all.
 We waste BILLIONS of pounds on lighting up the sky instead of the streets.


ANOTHER great reason to buy a Watch House Equatorial Platform .......


You may have noticed in the slideshow of "what is an Equatorial Platform" we show a camera and tripod on a platform.

This is a great use of the tracking ability of the platforms, which opens up a new area of astrophotography for you, wide field long exposure views,  if you buy a Watch House Equatorial Platform.


So if you have any sort of digital camera and a cheap £10+ tripod and want to take amazing images of the stars meteors, etc, then read on ...........


There is a great basic introduction to star shooting with a digital SLR on the web here :


Follow this basic start up guide and you will get good images immediately .

Of course you will be limited to exposure times of about 30 seconds or less, or you will see the stars trailing into little lines because of the Earth's rotation..........


But not if you set your tripod on an Equatorial Platform, so that your camera tracks the stars !


Just LOOK at what you can achieve from your own back garden ..........





See our Photography WITHOUT a telescope pages for the rest of the story. 



This an awesome planetarium program for the PC and Mac called Stellarium which is available from the developers as a free download.

 This program really is amazing and will transform your observing.

for example :

Locate any object

See the night sky from any latitude

See the sky as it will appear at any time

etc, etc, etc, etc


So we use it  as follows  :

set it to your latitude and longitude, then set the time to say 11pm, and you will see the sky as it will appear from your garden at 11pm tonight . Locate your targets by name, M number NGC number etc. Check what will be visible

Set up your observing list for the evening.

Look at Jupiter and see the positions of the moons, fast forward to show transits etc.


Really,  the best Free program EVER.

Click on the banner on the left to go to their website and download.


A great website in Sweden, set up to view the Northern lights on a mountain top,  has a digital SLR that takes a photo every 5 mins and posts to the web.
Click on their banner to go to the site.
 You can scroll  along about 1600 photos and watch the Aurora develop over the evening. Some GREAT images in January and a couple are reproduced below. Have a look each evening once it is dark and watch the evolution of the most amazing light show.


NASA have published an AMAZING video of the Northern lights taken from the ISS as it orbits over North America. re-posted loads of times on youtube etc , but you can see it HERE

Northern Lights from the ISS


Fame at last, well sort of ...
That image of the Europa transit that the boss is so proud of, well it made the front page of The Universe Today news site on 30th January 2012 . 
The proof ........


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