Astronomy Log

This seems a bit of a strange blog post title, but I was finding it difficult to get my LX200 telescope to actually find and track the sun when I was undertaking some solar observing.

The first time I found the Sun it was by chance, as it’s difficult when you can’t actually look at the Sun or use the viewfinder to locate the Sun.

There are a few different ways to locate the sun, but the reason I really wrote this post is to tell you about the new piece of kit I got for my Birthday for about £20, which now makes finding the Sun really easy.

I have a Sun location file which you can upload to your telescope which allows you to have the location of the Sun in your LX200 handset, you can find it on my downloads page.

I also read somewhere that you can locate the Sun when the reflection of the telescope tripod on the ground is at it’s smallest.

But I purchased the Astro Engineering AC466 item which turns your viewfinder into a solar viewfinder.

All it does is fit over the end of your viewfinder and it’s then tightened via a thumbscrew. It has a hole in one end and cross-hairs at the other end.

All you then need to do is then align the white spot, which is the Sun coming through the small hole onto the cross-hairs and the Sun is centered! Brilliant and easy for around £20.

The AC466 solar finder fits directly over the front of the standard 50mm finder of the type used on Meade®, Celestron, Sky Watcher and many other telescopes.

This week at the Institute of Astronomy in Cambridge we had a talk by Ken Day entitled “A Cook’s Tour of the Solar System” as part of the Introduction of Astronomy course I am partaking in via the Cambridge Astronomy Association.

Ken took us through all of the planets in the solar system, plus comets and asteroids. He gave explanations about each object in the solar system and backed up each item with some great full colour images in his presentation.

I picked up a new useful facts such as:

• The word “Planet” means wanderer in Greek.
• The Sun is 109 times the diameter of the Earth.
• Venera 9 the Russian probe to Venus in 1975 only lasted 23 minutes once it landed due to the harsh surface environment.
• Olympus Mons is the largest volcano in the Solar System which is on Mars.
• There are dark “spokes” in Saturn’s rings - something that I did not know.

There was no trip out to any of the IOA telescopes tonight, a bit of a shame as it was a clear night, but instead we were joined by Green Witch the astronomy retailers from near Cambridge.  They bought a few items with them including Philip’s astronomy book, some binoculars and a Skywatcher telescope and some eyepieces.  They also handed out flyer’s offering us 5% off anything we purchased.

Green Witch set up a Celestron NexStar 5 telescope outside and they gave us the chance to view Mercury and the Moon. Everybody rushed outside after the talk so there was a queue to view Mercury, which everybody wanted to see.

Whilst the NexStar was being re-aligned on Mercury (the scope seemed to drift a lot, and not track that well) it was strange to see how similar the menu options were on the Celestron to the Meade, as I have never used or really seen a Celestron NexStar before. After two cups of coffee it was time to go home.

Does your child dream of beng an astronaut with NASA? Well I found these Astronaut costumes for kids on the web in Orange and in White.

“Take one giant leap for mankind in our astronaut flight suit costumes! These high-quality flight suits are replicas of those worn by the astronauts and NASA flight crews, and feature chest and waist harness buckles, padded neck collar ring, and matching custom embroidered NASA vector cap”.

They look really good and they fit ages 4-8 years old. They cost £34.99 from The Science Museum store.

Buy a Kids Astronaut Costume here.

Week 2 of the Introduction to Astronomy course was presented by Peter Howell entitled “Sunshine and Green Cheese”. Peters talk covered details on the Moon and the Sun.

Peter started by talking about the Sun, and gave a great talk on every aspect of the Sun, including information that sunspots appear in magnetic pairs. Also that charged particles from the Sun give rise to the Northern and Southern lights. It was also interesting to hear that a supernova 10 billion years ago produced gold.

Peter then discussed in depth about the various stages of the moon, and why First Quarter is called what it is, and he pointed out all the Apollo landing sites on the Moon.  Peter also showed images of interesting areas of the Moon to look at, including Schroter’s Valley, Rupes Recta fault line and the Hadley Rille.

Peter handed out paper moon maps as well as sheets in order to allow you to construct your own sun dial (diptisch dial). It was very interesting to find out that the equation of time varies heavily between summer and winter, indicating that the Earth rotates at different speeds through out the year.

After the talk was over and we had tea, we ventured out to the Institute of Astronomy’s outside Observatory building which houses the library. The library room holds a number of very old and interesting astronomy and cosmology books together with the latest astronomy journals and magazines.

Whilst in the library room we managed to see slides taken between 1945 and 1985 by the Schmidt telescope. 

The Schmidt instrument was built in 1952 by Grubb-Parsons of Newcastle-upon-Tyne and replaced an older telescope in the existing dome, which had been made by T. Cooke & Sons Ltd. of London & York at the time of the move of the Solar Physics Observatory from South Kensington to Cambridge.

It is a `Classical Schmidt’ - the simplest and most efficient form of the ingenious wide-field camera invented in 1930 by Bernhard Schmidt of Hamburg Observatory. Light from the sky falls upon a 61 cm (24-inch) mirror with a spherical reflecting surface, at the bottom of the tube. It is reflected to a focus in the centre of the tube and half-way up it, 163 cm (64 inches) from the primary mirror. At the focus a photographic plate P 15 cm (6 inches) in diameter, which must be bent to fit a curved surface, records the star images in an area of sky 5 degrees in diameter. (The full Moon is half a degree in diameter.)

Below are some images I took with my mobile phone that were produced by the Schmidt Camera of Halley’s Comet in 1986 and another part of the cosmos.

This is the second edition of Michael Covington’s Astrophotography for the amateur book.  It is nice to find a book solely on astrophotography, as that’s what interests me most, I always like to come in from the cold with some images or video to work on.

Although the title of the book is astrophotography for the amateur, I did find this book to be quite in depth and it does include non-beginner topics such as exposure tables, and lots of mathematical equations. The book does not include many colour images, only in a section in the centre of the book.

Astrophotography for the amateur is broken down into four main sections; simple techniques, advanced techniques, photographic technology and digital imaging.

The first section takes you through photographing stars without a telescope, and how to shoot eclipses, the moon, comets and meteors.

The second section on advanced techniques takes you through performing prime focus photography, which is where you connect the camera directly to the telescope.  This section also discusses dealing with tracking, vibration, unsteady air, dew and more. This section finishes off detailing piggy backing your camera on your telescope, building and using a barn door tracker, using lenses, dealing with light pollution and how to get the best polar alignment.

The third section entitled photographic technology covers using traditional SLR cameras, there is no mention of digital cameras in this section.  This section does include everything you wanted to know about SLR cameras though, such as about film, various cameras and developing and processing your shots.

The final section is all about digital imaging, including file compression, how to manipulate colour, combining images, printing, smoothing, sharpening, working with histograms and all about CCD imaging.  The CCD section talks about how CCD works, aiming and focusing, exposures and focal lengths and more.

Astrophotography for the amateur also includes six appendices, such as exposure tables, plans for an electronic drive corrector and about photographic filters as well as an appendix on mathematical analysis of polar-axis misalignment.

So as you can tell there is a lot of content in this book, and it covers lots of areas of astrophotography and it packs in a lot of information. Overall a very good book on astrophotography, just a shame that DSLR cameras were not covered in any detail, perhaps in the next edition the SLR section will be changed to a DSLR section.

Buy Astrophotography for the Amateur Book