Linux for Astronomers
I've looked at specialty distributions that were created for engineers and biologists in previous articles, but these aren't the only scientific disciplines that have their own distributions. So in this article, I introduce a distribution created specifically for astronomers, called Distro Astro. This distribution bundles together astronomy software to help users with tasks like running observatories or planetariums, doing professional research or outreach.
From the very first moment of booting up Distro Astro, you will notice that this distribution is aimed at astronomers. The look and feel of items, from the boot splash screen to wallpapers and screensavers, have all been given an astronomical theme. Even the default wallpaper is a slideshow of Hubble images.
Figure 1. Even the boot splash screen has an astronomy theme.
Figure 2. Once you boot up, you have desktop shortcuts pointing to a series of different tasks.
There is also a unique feature called Nightvision Mode that lets you switch the color theme to red-based colors to help maintain your night vision when using the computer during observations. Clicking on the menu item will toggle this mode on or off.
Figure 3. For night observations, you can turn on Nightvision Mode.
The advantage of having a domain-specific distribution is that all of the software you likely will use is bundled together and installed. Ideally, you shouldn't have to install anything other than the distribution itself.
The first task in astronomy is to collect images of the sky. In Distro Astro, the INDI library is pre-installed for you. This library is the main interface that is used in telescope control. With it, you can control telescopes from Meade, Celestron and Orion, among others. If you are lucky enough to have a domed observatory, you even can control commercial domes, such as those from Sirius Observatories.
To be able to make your observations, you need a front end to talk to your hardware. This access is provided through clients like KStars, XEphem and Cartes du Ciel, which use the INDI library to talk to your telescope.
After aiming your telescope, you need to collect some images or do some astrophotography. While you can do some of this with software like KStars, you have software specifically designed to do image capture. Some, like wxAstroCapture, are specifically written for use in astronomy. With it, you can set up automatic guiding and batch image collection. You then can go have a nice hot cup of coffee while your telescope collects your data. To help you keep track of all of these observations, you can use the Observation Manager, a logging program to maintain your records.
Figure 4. You can do image capture from your telescope with wxAstroCapture.
Once you have made your observations, you need to process them and do some science with them. The first step is to do image processing. This might be some filtering or some sort of feature identification routine. One common task is image stacking, so much so that Distro Astro includes the RegiStax package. With it, you can set alignment points and do image analysis on full stacks of images. You even can set up batch processes and run on multiple CPUs, if you have them.
Figure 5. With RegiStax, you can do image processing on full stacks of images.
You can do more complex image analysis with tools provided by IRAF (Image Reduction and Analysis Facility). Sometimes, however, the functions already available aren't enough, especially when you are doing leading-edge research. In those cases, you are forced to write your own algorithms to do this work. ImageJ is a very popular choice that is available in Distro Astro. With it, you can develop and write your own algorithms in Java.
Unfortunately, the weather doesn't always allow for observations. So, what can you do if you have been stuck away from the telescope for days on end? Distro Astro includes a number of sky chart programs to allow you to plan out your future observations. They also are really useful for budding astronomers. You can use packages like Cartes du Ciel to learn about the sky above your head. And there are several other options, including Stellarium and Celestia. If you are more interested in deep sky objects, there is a package called Where is M13?. This package shows objects from several catalogs, such as the Messier, Caldwell, Collinder or NGC catalogs. The unique feature of this software is that it can locate these deep sky objects in three dimensions. That way, you can start to get a feel for where in space these objects actually are.
Figure 6. With Carte du Ciel, you can learn more about the sky.
Figure 7. Where is M13? lets you see where deep sky objects are located around you in three dimensions.
Part of science is outreach, sharing your findings with others and inspiring them. One way of doing this is by putting on a planetarium display. This is a way to expose a large number of people to the wonders of the sky all at once. Several different software packages are included in Distro Astro that can talk to planetarium projectors. Packages like Celestia and OpenUniverse can be used with non-fisheye projectors. If you have a more professional fisheye projector, there is a modified fork of Stellarium called Nightshade Legacy that is included in Distro Astro. The original version of Stellarium also is included, giving you some choice in what is available.
With Distro Astro, you now easily can set up that observatory computer or configure a machine to do your research runs on. And, with a live CD option available, you have no excuse to keep you from downloading an ISO and giving it a try. And with all of the packages included, you should be able to burn a CD and run with nothing else to install.
Limited Time Offer
Take Linux Journal for a test drive. Download our September issue for FREE.
Topic of the Week
The cloud has become synonymous with all things data storage. It additionally equates to the many web-centric services accessing that same back-end data storage, but the term also has evolved to mean so much more.