Issue #527: The New Stellarium

I don’t claim to be some kind of software guru, but I have been using astronomy software since computers first came to our avocation. Most of you know that, and I am often asked which software I use. Those asking are sometimes disappointed when I say, “Whatever is cheap and simple” rather than “The latest version of TheSky X Professional (or Maxim DL).” In part, that’s because I am cheap. And it’s also in part because the things I do in astronomy today are simple enough that they could probably be accomplished with a 20-year-old copy of Megastar.

Just because I don’t spend a lot/any money on the software than runs on my PCs (no Mac here despite my not infrequent threats to go Apple) doesn’t mean my astronomy programs aren’t capable of doing far more than I do with them. We are in a golden age of incredibly capable astronomy freeware with softs like Cartes du Ciel, Deep Sky Stacker, Sharpcap, Astrotortilla, Auto Stakkert, ASCOM, Registax, and, the subject of today’s article, Stellarium.

Yes, there are tons of excellent planetarium programs, freeware and payware planetarium programs, beyond the above mentioned Cartes (a long time favorite of mine and a wonderful piece of software) and TheSky X, but what I use more than anything else today is Stellarium. Why? It’s simple and it’s pretty and that is exactly what I appreciate at the moment. It also does everything I need, and could do far more than I ask it to. If you’re interested in the basics of Stellarium, including how to install and configure it, see this article (from over five years ago, hard as that is for me to believe). Today, we’ll mostly be looking at what’s new in the latest release, Stellarium 15.1.1.

To make the above-linked long story short, Stellarium, in addition to being free, is a relatively quick download, and while, like any astronomy software, it needs to be configured, it’s not that tough. For the most part, there are no submenus of submenus of submenus. You get some fairly clear choices in a few (multi-tabbed, admittedly) windows, “Location,” “Sky and Viewing Options,” and “Configuration.” It’s all easy to do and it’s fairly obvious what you should do without even looking at help pages.

Without (top) and with (bottom) DSS (click to enlarge)...

Even setting up a connection to a telescope is not that bad. It’s duck soup if you can use the program’s built in telescope drivers (Celestron, Meade, Losmandy, SkyWatcher, Argo Navis). If you have a non-compatible telescope, you’ll have to use an add-on helper program, StellariumScope to give the program access to the multitudinous ASCOM telescope drivers, but even doing that is fairly simple.

How much computing horsepower does it take to run Stellarium? For the current version you’ll want a reasonably fast processor, but a 2.4 gig one like those in even the cheapest boxes from BestBuy is more than sufficient. Most important is a video card that supports the Open GL graphics system. You’ll also want Windows 7 and up, OSX and up, or a reasonably current flavor of Linux/Unix as your operating system. You can download older versions of Stellarium to accommodate older OSes and video cards, but you really don’t want to.

What is the first thing you will notice the first time you boot up Stellarium? Just how beautiful it is. This software is used in conjunction with projectors in planetariums, and it’s easy to see why. Its sky is as realistic as those in the most expensive apps. Weather, fog, passing satellites (actual satellites), sporadic meteors, beautiful horizon scenery, and a luscious looking sky with a superb rendition of the Milky Way are all there. You can download plenty of additional stars, and the program contains thousands and thousands and thousands of deep sky objects. Movement around the sky, dragging it with a mouse, is wonderfully responsive.

But those of you who’ve, like me, been using the program for a while know all that. What you want to know is, “Why should I go to the trouble of downloading the new one and going through that configurating again?

Here’s a (partial) list of what’s new from the program’s website:

- The Digital Sky Survey (DSS) can be shown (requires online connection).

- AstroCalc is now available from the main menu and gives interesting new computational insight.

-A lot of bugs have been fixed.

- Added support of time zones dependent by location.

- Added new skyculture: Sardinian.

- Added updates and improvements in catalogs.

- Added improvements in the GUI.

- Added cross identification data for stars from Bright Star Catalogue, 5th Revised Ed.

That first thing, DSS, is the money here. Being able to download and overlay Digitized Sky Survey images on Stellarium is a wonderful tool. Sure, you need an Internet connection, but it’s getting to the point where many star parties provide that. Not only are the charts prettier with DSS, they are more detailed. Compare the program’s normal display of M33, the Triangulum Galaxy, to one showing the DSS image of M33 (above). What’s really cool about this feature? Plenty of planetarium programs allow you to superimpose DSS images over their charts, but most require you to be zoomed in tight. Not Stellarium. The image at the beginning of this post is 30-degrees of Cygnus with DSS “on.”

Astrocalc...

While the program’s developers warn the Digitized Sky Survey feature is still somewhat experimental, it worked flawlessly for me. Occasionally, when using wide fields of view, there were a few “stitching” artifacts, but these didn’t bother me or cause problems. DSS is reason enough to upgrade to the new Stellarium. The current release is 15.1.1, btw, because the initial 15.1 build had problems with missing dlls, which prevented you from downloading the additional star catalogs offered for the program.

“Astrocalc” is Stellarium’s text-based ephemeris module. You can now overlay it on the screen with a push of the F10 button. In addition to ephemerides, this tabbed window will give positions for comets (clicking on a comet in the list will center it on the chart), find conjunctions, and display a graph showing altitude versus time for the selected object. That last is similar to the observability graphs offered in several other programs, and it is a very popular and useful tool for me.

The other additions, like a new “sky culture” (constellation system), are more minor, but still welcome, and undoubtedly useful to some of the program’s large base of users. As above, Stellarium is used by more than a few planetariums and science museums. More important to most of us, I suppose, are the updates and expansions to the program’s deep sky and star catalogs.

There’s always that ever-popular question among deep sky hounds, “How many DSOs does it got?” I don’t know that there’s a numerical total anywhere on the Stellarium website, but the DSO catalog has undoubtedly grown with the last couple of releases. For example, zooming in on a field in Coma revealed plenty of magnitude 16 PGC galaxies. I am more interested in imaging and observing the bright and spectacular galaxies, clusters, and nebulae these days (I used to chase Arps, PGCs, and UGCs), but if I were currently interested in the dimmest of the dim, I’d still be just fine with Stellarium.

What’s the experience of using the program like for those who haven’t tried it yet? Most people tend to think of this as a very visual, GUI oriented program, and it can be that. Grab the sky and drag it around, use the roller ball on your mouse to zoom. It’s a silky smooth and, yeah, visual experience. Strangely, however, one of Stellarium’s major strengths hearkens back to the earliest days of computing. What it’s very strong with is hot keys.

Yes, it’s cools to mouse over to the left side of the screen (which makes one of the program’s tool-icon-menus appear), click that pretty “find” icon, and locate what you want with the aid of the window that comes up. Cool, yeah, but somewhat annoying out on a dark observing field. Much easier/simpler is pressing F3, which summons that same window without mousing around and clicking. Much of what you need to do with the program can be done quickly with F keys and key combos. , for example, takes you do the eastern horizon post-haste.

It's just so pretty!

The ability to do things quickly with hot-key combos doesn’t end with the things built into the program by the developer. Stellarium includes a powerful scripting system that will allow you to compose scripts to do things with a few key presses, things as simple as pointing at a certain object, or as complex as taking you on a tour of the best NGC objects.

How do I use Stellarium? Basically, in three ways. First, I use it to give me quick “What’s up?” looks at the sky. You know, “What’s high in the east right now?” After Windows changed enough that that DOS oldie but goodie, Skyglobe, would no longer run, I cast about for a program that was quick to load and would let me get to my chosen horizon in a hurry. Initially, I used the free soft I got with my Edge800/VX telescope four years ago, the lowest level of Bisque’s TheSky X, the First Light Edition. That’s a nice but very limited program (natch), so I was pleased to be able to ditch it for the recent releases of Stellarium, which load quickly on my modern PCs, and which offer those quick hot-keys to allow me to get to anything and anywhere.

Secondly, I use Stellarium when writing observing articles, whether for this blog or for Sky & Telescope. The program has an excellent measuring tool that allows me to easily determine that NGC Umptysquat is 3 degrees northwest of M Whatsit.

Finally, I use Stellarium in the field with my telescope. While there are built-in drivers for all my mounts, I generally use the SteallariumScope program and ASCOM drivers, since ASCOM gives me some things the built-in drivers don’t, like a little onscreen hand control. That allows me to center objects I am imaging without messing with the real HC (and prevents my editor from complaining about my poorly centered/composed astrophotos).  Going to objects with Stellarium is a breeze, by the way. Select an object, hold down the CTRL key and press “1.” That’s all. No icons to hunt or menus to navigate.

In the field, I often use Stellarium alongside a planner/logger—SkyTools, Deep Sky Planner, or Deepsky. While you can’t interface Stellarium with Deep Sky Planner as you can some other planetarium programs, I don’t find that a huge problem. I locate an object in DSP’s database, switch to Stellarium, hit the F3 key, and type in the object identifier, Not a big deal. And then I just do my thing with Stellarium and my telescope. I have never had any problems with or program crashes in the field. Yes, computers can be cantankerous, but Stellarium is exemplary for its good behavior.

And there you have it. If you are a Stellarium user, you’ll want to upgrade ASAP in order to get the DSS feature. Not a Stellarium user? As I said earlier, there are many great free planetariums these days, like Cartes and Hallo Northern Sky, but since there’s no money involved, why not give Stellarium a try; you just might like its way of doing things. You are firmly in the TheSky X or Starry Night camp? Again, it don’t cost nuthin’ so why not try Stellarium? There’s a lot to be said for “simpler.” Me? I’m allergic to menus within menus within menus, and that’s one of the reasons I’ll be rolling with Stellarium for a while, I think.