Software for Astronomers

Software isn’t something with which the analogue astronomers of yesteryear would have been familiar.

But the World has changed and I have been known to boot up a computer, so I’ve decide that it’d be a good idea to start listing the software that I find most useful for astronomy.

Some of it I use only on my laptop and others on mobile devices. Most of it is open source or free to use which goes to show what a generous lot the astronomical community are. Thank you all.

Carte du Ciel (Skychart)

This software I find very useful for creating custom finder charts and planning observations. You can define observing lists as text files (which I like very much) and it comes with a range of object catalogues built in. You also have access to many Vizier Virtual Observatory catalogues which I use in preference to the standard ones. I use the Washington Double Stars (WDS) and the International Variable Stars Index (VSX) ones frequently. I’ve also added the optional, and large, UCAC4 catalog to cover the fainter stars.


This is the standard open source planetarium software that we point out to all beginners. Why? Because it’s free and easy to use, at least for the basic purpose of showing you what’s in the sky at the moment. You set up your locations and there you go.

Virtual Moon Atlas

Want to get an idea of what’s to see on the lunar surface at the current, or any other, point in the lunation cycle? This is the open source application for you. It’s a great piece of software for planning those lunar sessions, and it’ll even suggest the best on offer tonight depending on the aperture of your telescope. It’s also a great learning tool. Unfortunately this has become harder to support on the Mac platform because of a lack of the correct libraries. Works on older MacOS.

Aladin Sky Atlas

If I want to play with those professional sky surveys – the Digitized Sky Survey (DSS) or it’s electronic equivalent the Sloan Digital Sky Survey (SDSS) for example – generating overlays of catalogue data, proper motions of stars and multispectral goodness, then this is a very handy application. It’s developed by the Centre de Données astronomiques de Strasbourg (CDS) and is free in online and desktop forms. I also use the Lite version to embed these data on the Webb Deep-Sky Society website.


An desktop Java application provided free of cost by the American Association of Variable Star Observers (AAVSO). A bit more specialised this one. I use it to generate light curves, phase diagrams and perform analysis on variable stars, principally the ones I follow, but not always. A useful tool with some great features.

Sky Safari

Probably the best planetarium software available on Apple devices in my opinion. It’s available for all sorts of platforms and it’ll cost you money, but it’s worth it. I’ve only ever used it on my iPad 2.

You can do all sorts of things with this including driving a compatible telescope or using it as a finder – if you hate night vision and never want to see anything in the deep-sky. But I just use it as a pre-observing planning aid and to learn more about the night sky, especially on those cloudy nights.

Moon Calendar

This iPhone/iPad app is great when you’re planning a lunar session, or a meeting with deep-sky observers. It’s not free, but it’ll keep you nicely up to date with the phases of the Moon and also show you the altitude and azimuthal positions throughout the day. So there’s no reason not to know where the Moon is at any given time.