2
1 Introduction
of observational astronomy or are out of practice. It should also be useful for the
amateur astronomer who wishes to do some scientific work with a home instrument.
One exciting aspect of astronomy is that it is a modern science in which even an
amateur can do highly useful research.
1.2 Required Equipment and Software
For the purposes of this book, it’s assumed that you have access to a permanently
mounted and fixed telescope. We further assume that it is a Schmidt–Cassegrain
telescope (we’ll discuss specifically what this is later on). The most widely known
manufacturers of small telescopes are Meade and Celestron, whose telescopes are
the most commonly used by universities. (The make of the telescope affects only a
small portion of this book, so don’t worry if yours is different!)
We’re also going to assume that the telescope has a mount that is capable of
sidereal tracking, and also that it has an astronomical digital camera. The camera
should be able to provide guidance information to the mount. Also, you will need
scientific-grade astronomical filters (ideally, these will be contained in the filter wheel
that is part of the camera).
Your telescope may be controlled by either a computer or a hand controller. The
camera will always be computer-controlled. There is a range of different software
applications for controlling camera and telescope; the most popular are ccdSoft and
MaxImDL. These products are broadly similar, although for the purposes of this
book, we will be using MaxImDL. In addition, you may also find that your telescope
has a powered focuser. This tool isn’t essential, but it is a useful add-on.
Throughout this book, you will be asked to manipulate the images you take with
your camera/telescope combination. Both ccdSoft and MaxImDL are capable packages, but both have associated licensing fees. There are also freeware image manipulation applications available for Windows, OS X, and Linux. In this book, we will
be using SAO DS9, Aperture Photometer Tool (APT), AstroImageJ, and SALSAJ.
Some universities may require you to use certain professional-grade applications. A
common example of such a tool, IRAF, is versatile and fast, but is designed only
for Linux (which also extends to OS X in practice). IRAF requires the use of a
command-line interface and is notorious for its steep learning curve, so you may find
that to be something of a speed bump when you start out. However, one of IRAF’s
merits is that it can be scripted to run a series of linked commands. This can greatly
speed up many image analysis processes. Most of the image manipulation that this
book will cover can be done in IRAF if you wish.
This book also covers tasks that can be carried out using commands in the Python
programming language. Python is becoming increasingly popular in professional
astrophysics, and I can’t recommend it highly enough as a first language. I also
highly recommend learning a programming language, as it will help you in your
course and also for getting a job post-degree. Python is open source (i.e., it’s free),
multi-platform, well supported, and easy to check for errors. It has many powerful
1 Introduction
of observational astronomy or are out of practice. It should also be useful for the
amateur astronomer who wishes to do some scientific work with a home instrument.
One exciting aspect of astronomy is that it is a modern science in which even an
amateur can do highly useful research.
1.2 Required Equipment and Software
For the purposes of this book, it’s assumed that you have access to a permanently
mounted and fixed telescope. We further assume that it is a Schmidt–Cassegrain
telescope (we’ll discuss specifically what this is later on). The most widely known
manufacturers of small telescopes are Meade and Celestron, whose telescopes are
the most commonly used by universities. (The make of the telescope affects only a
small portion of this book, so don’t worry if yours is different!)
We’re also going to assume that the telescope has a mount that is capable of
sidereal tracking, and also that it has an astronomical digital camera. The camera
should be able to provide guidance information to the mount. Also, you will need
scientific-grade astronomical filters (ideally, these will be contained in the filter wheel
that is part of the camera).
Your telescope may be controlled by either a computer or a hand controller. The
camera will always be computer-controlled. There is a range of different software
applications for controlling camera and telescope; the most popular are ccdSoft and
MaxImDL. These products are broadly similar, although for the purposes of this
book, we will be using MaxImDL. In addition, you may also find that your telescope
has a powered focuser. This tool isn’t essential, but it is a useful add-on.
Throughout this book, you will be asked to manipulate the images you take with
your camera/telescope combination. Both ccdSoft and MaxImDL are capable packages, but both have associated licensing fees. There are also freeware image manipulation applications available for Windows, OS X, and Linux. In this book, we will
be using SAO DS9, Aperture Photometer Tool (APT), AstroImageJ, and SALSAJ.
Some universities may require you to use certain professional-grade applications. A
common example of such a tool, IRAF, is versatile and fast, but is designed only
for Linux (which also extends to OS X in practice). IRAF requires the use of a
command-line interface and is notorious for its steep learning curve, so you may find
that to be something of a speed bump when you start out. However, one of IRAF’s
merits is that it can be scripted to run a series of linked commands. This can greatly
speed up many image analysis processes. Most of the image manipulation that this
book will cover can be done in IRAF if you wish.
This book also covers tasks that can be carried out using commands in the Python
programming language. Python is becoming increasingly popular in professional
astrophysics, and I can’t recommend it highly enough as a first language. I also
highly recommend learning a programming language, as it will help you in your
course and also for getting a job post-degree. Python is open source (i.e., it’s free),
multi-platform, well supported, and easy to check for errors. It has many powerful