Stargazing is for everyone. All you have to do is step out into your garden or look out your window on a clear night and the wonder of space is yours to discover. It’s a nice idea, but does it actually reflect the reality faced by many of us?
Perhaps you live in the middle of a city, where light pollution from cars, buildings, and street lamps drown out all but the very brightest stars? Perhaps you live in a place where cloudless nights are few and far between? Or perhaps after a busy day, standing in your garden and squinting into space doesn’t sound quite as appealing as some well-earned rest and self-care?
Luckily there is a completely free Planetarium software called Stellarium that anyone can download to their computer that allows you to explore the heavens from the comfort of your own home. There is also a mobile app that is mostly free but requires you to pay for some of the more advanced features.
Since I began working as a Planetarium presenter it’s a tool that I’ve found to be invaluable. It’s also a lot of fun to just play around with.
Stellarium can seem a little daunting when you first download it. But I’d like to share some of the more basic functions that I’ve found myself using the most.
Head to stellarium.org. You’ll find at the top of the page a series of operating system logos. You’ll also see a link to download a Stellarium User Guide that will come in very handy if you want to take a deep dive into everything Stellarium’s capable of.
Click on the operating system logo that applies to your computer and download the installation file. Once the file is downloaded, find it in your Downloads folder. Double click on it and follow the installation instructions.
Once Stellarium is launched the first thing you’ll see is a grassy landscape in front of you and the sky overhead. You’ll find that you can move yourself around by either left clicking and dragging your mouse or by using the arrow keys.
Stellarium will show you the view from whatever town or city you’re currently physically located at by checking your network. You can however change your location in Stellarium.
Bring your cursor over to the left-hand side of the screen. A menu will appear with a number of tools. Choose the top option labelled Location Window.
You’ll see drop down menu boxes that enable you to change the view and look at the sky from anywhere you want to in the world. You can even move yourself to another planet or moon!
Changing your location will not change the landscape, but you can do that by selecting the Sky and Viewing Options Window from the left-hand menu and clicking on the Landscape tab to choose from a selection of landscapes.
When you’re done with a window, click on the x in the top right-hand corner to get rid of it.
Below the Location Window on the left-hand menu is a Date/Time Window. Click on that and you’ll be able to change the date and time to anything you want. You can look at the sky tonight or look at the sky on the night you were born. You can even view the sky thousands of years in the past or future!
If you bring your mouse to the bottom of your screen, you’ll find another menu with a number of useful tools. Many of these tools can also be accessed via keyboard shortcuts, and personally I find these a lot easier to use. Here is a list of some of the shortcuts I’ve found myself using the most.
Left click: Select any object in the sky — a star, a planet, or a satellite.
Right click: When you want to move on from your selected object, simply clear your selection.
Space Bar: Get whatever you’ve selected into the centre of the screen.
Page Up: Get a closer look at whatever you’ve selected by zooming in.
Page Down: Zoom out.
Alt + S: Some of the more notable stars are automatically labelled but you can turn those labels off and on again.
Alt + P: Planets are automatically labelled but you can turn those labels off and on again.
Ctrl + Shift + M: Meteor showers are automatically highlighted with green marks but you can turn these off and on again.
G: If the landscape is spoiling your view, turn it off. Pressing G again will turn it back on.
F: There’s a hazy fog above the landscape that’s particularly noticeable at night. If you want to recreate a completely clear night you can turn it off. Pressing F again will turn it back on.
Q: Turn the red compass labels on and off
A: If you’d like a completely unhindered view of the stars you can even turn off Earth’s atmosphere. This is particularly handy if you’d like to see the position of the stars during the daytime. Pressing A again will turn it back on.
M: The Milky Way is beautiful path of dense stars stretching across the sky. It’s our view of the disk of our home galaxy from within. It isn’t visible from most cities and towns due to light pollution. If you want to try and recreate this experience, turn off the Milky Way. Pressing M again will turn it back on.
Alt + Shift + Z: Just like the real sky, you’ll occasionally see little dots move across the sky. These are satellites orbiting the Earth. They’re used for a number of purposes, including communication and defence. You can left click on it to find out it’s name, or you can press Alt+Shift+Z to label every satellite. Press Alt+Shift+Z again to make the labels vanish.
C: If you’re having trouble making out all the constellations you can turn on the constellation lines. Pressing C again will turn them off.
V: This button will make labels for every constellation appear. Press it again to make them vanish.
R: View constellation artwork by Johan Meuris and press the button again to make the artwork vanish.
How do I view only one constellation?
If you’d only like to select one constellation head to the left-hand menu once again. Click on Configuration Window. Then click on the Tools tab. Tick the fourth box down, labelled Select Single Constellation. Now, whenever you select a star, pressing C, V, or R will make visible only the lines, label, or art of the constellation of which that star is a part.
Is that it?
This article only scratches the surface of everything that Stellarium is capable of. In fact, I’m still discovering all the things it’s possible to do with it myself. As well as the User Guide found on stellarium.org you can also access a guide on your computer by right clicking on your Stellarium desktop shortcut, clicking Open File Location, and scrolling until you find a folder labelled Guide. Within that folder you’ll find a pdf of a complete user’s guide to Stellarium.
Hopefully this article has offered you a starting point that will allow you to gain some confidence with the basics before taking a deep dive. Good luck!
If you’d like to find out a bit more about the basics of Stellarium then take a look at the video below. It was originally streamed on Facebook as part of a series of videos in which I use Stellarium to explore the night sky. If you’re new to stargazing and you’re not sure where to start looking then why not take a look at my article - Spring stargazing from your window: Where do I start?