Posted on Thursday, September 25, 2014
How To Observe The Sun Safely by Lee Macdonald
Rating: 9/10
Historically it is known that sunspots were observed in ancient China and they were also seen by one of the first astronomers to point a telescope towards the sky – Galileo Galilei. While in the first case thin jade disks were used, in many of the other cases the Sun would be observed through clouds when near the horizon or through a darkened glass. Was it safe however ?
In Macdonald’s book the reader finds different methods and a variety of equipment that can be used for observing our nearest star without any damage to their eyesight and also gets ideas on what to do with the observations.
The cheapest way to observe the Sun if you’ve already got a telescope is by using the projection method – you either attach a screen to the telescope or somewhere nearby, aim the telescope at the Sun by looking at the telescopes shadow (never look at the Sun through a normal telescope!) and projecting the image on the wall. One gets a nice view of the Sun in white light, and you can observe sunspots quite well.
Another option is to get a solar filter for your telescope or a special solar telescope , which are able to show more features on the Sun. For example with a Hydrogen Alpha telescope one can see solar prominences on the edge of the solar disk as well as filaments – prominences seen edge-on on the solar disk, as well as dark and bright spots on the Sun.
In addition to the equipment one probably want to know what to look for during observations and whether or not the observations would be useful. In this book you can find out how to calculate the sunspot number and even how to record the locations of sunspots.
I’ve been a somewhat active Sun observer for the past two years, and I found the book very useful, especially since I mostly photograph the Sun, and this book has two chapters dedicated to imaging the Sun - with a DSLR and with a webcam.
If you’re thinking of starting to observe the Sun, this is a great book to get more information about all the available options.
Labels: book review, Lee Macdonald, observations, sun