How to Use Stellarium: A Complete Beginner's Guide to the Free Planetarium

Quick Answer: What Is Stellarium and Why Should You Use It?

Stellarium is a free, open-source planetarium that renders a realistic 3D sky on your computer or phone. You enter your location and date, and Stellarium shows you exactly which stars, planets, constellations, and deep-sky objects are visible at that moment — with proper positions, brightness, and even atmospheric effects. It is the single most useful tool for planning an observing session, identifying an object you spotted, or learning your way around the night sky.

The desktop version is the full-featured powerhouse used by amateur astronomers worldwide. The mobile version (Stellarium Mobile) puts the same sky map in your pocket, with a touch-friendly interface optimized for field use. Both versions are free to download, though the mobile app offers a paid Plus version with additional catalogues and telescope control.

Whether you are a complete beginner trying to identify your first constellation or an experienced observer planning a deep-sky imaging run, Stellarium has the tools you need. This guide covers the desktop version (Windows, Mac, Linux) in detail, then explains the mobile version at the end.

1. Downloading and Installing Stellarium

Stellarium is available for all major platforms. Here is where to get each version.

Desktop Version (Recommended for Planning)

Visit stellarium.org and click the download button for your operating system. The desktop version is completely free — no registration, no ads, no paid tiers. It runs on Windows 7 and later, macOS 10.13 and later, and most Linux distributions. The installer is approximately 200 MB and includes a full catalogue of 600,000 stars (expandable to 210 million with an optional add-on catalogue).

Mobile Version (Best for Field Use)

Stellarium Mobile is available on the Apple App Store and Google Play Store. The free version includes all basic features: sky display, object search, constellation art, and time travel. The paid Plus version ($19.99) adds deep-sky object images, telescope control, a larger star catalogue, and the ability to simulate your eyepiece's field of view. For beginners, the free version is more than sufficient.

Web Version (No Installation Required)

If you cannot install software, Stellarium also offers a web version at stellarium-web.org. It runs in any modern browser and includes the core sky simulation features. It is less responsive than the desktop version but works perfectly for quick checks.

2. First Launch: Setting Your Location and Date

When you first launch Stellarium, it defaults to showing the sky from Paris, France, at the current date and time. The first thing you should do is set your actual observing location.

To set your location: Click the location icon in the left toolbar (looks like a small map pin) or press F6. Type your city name in the search box. Stellarium contains a built-in database of thousands of cities. Select your city from the dropdown and click "Use as default." If your city is not listed, you can enter your latitude and longitude coordinates manually — a GPS phone app or Google Maps can provide these.

To set the date and time: Click the time icon in the left toolbar or press F5. A calendar and time selector appears. You can set any date and time to see what the sky looked like in the past or will look like in the future. This is the "time travel" feature that makes Stellarium so powerful for planning observing sessions.

To return to the current sky: Press the space bar or click the "Set time to now" button (a small clock icon) in the time control bar at the bottom of the screen.

3. The Interface: A Quick Tour

Stellarium's interface is clean and minimalist. Here is what you need to know about the main screen elements.

The main sky view occupies the entire screen. As you move your mouse, the cursor changes to a hand icon — click and drag to pan across the sky. Scroll to zoom in and out. The sky renders in real time, including stars, planets, the Moon, the Milky Way, and atmospheric effects.

The left toolbar contains icons for the most common functions. Hover over each icon to see its function. The most important ones (top to bottom) are: Sky and Viewing Options (F4), Search Window (F3), Location Window (F6), Date/Time Window (F5), and Configuration (F2).

The bottom toolbar controls the time flow. Play, pause, and speed controls let you accelerate time to see how the sky changes over minutes, hours, or days. This is invaluable for planning: you can watch when a planet rises, how high it climbs, and when it sets.

The status bar at the bottom of the screen shows your current location, date, time, and the object under your cursor (if any). When you hover over a star, planet, or deep-sky object, its name, magnitude, constellation, and distance appear here.

Keyboard shortcuts are the fastest way to control Stellarium. The essential ones are: F3 (search), C (constellation lines), V (constellation labels), A (atmosphere), G (ground), and the space bar (centre on selected object). We cover more shortcuts in the Pro Tips section below.

4. Finding Objects: Planets, Stars, and Deep-Sky Targets

The most common thing you will do in Stellarium is find an object and confirm whether it is visible from your location at a given time. Here is how.

Press F3 or click the Search icon. Type the name of the object you are looking for — "Jupiter," "Andromeda Galaxy," "M42," "Saturn" — and press Enter. Stellarium instantly centres the view on that object and displays a label with its name and basic information. If you have the ground displayed, you will see whether the object is above or below the horizon.

Click on any object to select it. A panel on the left side of the screen appears with detailed information: right ascension and declination (RA/Dec), altitude and azimuth, magnitude, distance, and for planets, phase illumination percentage. This panel also includes an "Info" link that opens a more detailed page for the object.

To browse objects by category, open the Sky and Viewing Options panel (F4) and go to the "Markings" tab. Here you can enable display of Messier objects, NGC objects, and other catalogues. Once enabled, these objects appear as coloured symbols on the sky map — click any one to learn more about it.

Pro tip for finding faint objects: Disable the atmosphere (press A) and turn off the ground (press G) to see how the sky will look from a dark-sky site. You can also adjust the limiting magnitude in the Sky and Viewing Options panel to show fainter stars than the default setting, helping you identify guide stars for star-hopping.

Once you have identified your targets, you can plan your entire observing session. Stellarium will show you the order in which objects rise, their highest elevation, and when they become too low in the sky for good viewing. This is far more reliable than using a generic astro app or website because it accounts for your exact location and local horizon. See our star chart guide for more techniques on navigating the sky.

5. Time Travel: Planning Future Observations

Stellarium's time-travel feature is its most powerful tool for planning. Here is how to use it effectively.

Set a future time by pressing F5 or clicking the date/time icon. Set the date to your planned observing night and the time to when you expect to be set up (typically 30 minutes after sunset for the best balance of darkness and convenience). The sky display updates instantly to show exactly what you will see.

Use the time acceleration controls (bottom toolbar) to watch the night unfold in fast-forward. The ">" button increases speed to 10×, the ">>" to 100×, and ">>>" to 1000×. At 1000×, you can watch the entire night pass in about 30 seconds — seeing which objects rise, peak, and set. This is the best way to plan an efficient observing sequence: identify which objects will be highest (best positioned for viewing) at each hour.

Check object altitude throughout the night. Select any object and click on it. The information panel shows its current altitude. As you accelerate time, watch how the altitude changes. For the best views, plan to observe objects when they are at least 30° above the horizon — lower than that, and atmospheric turbulence and extinction degrade the image noticeably.

Time travel is especially useful for planning observations of Saturn opposition, solar eclipses, and meteor showers — events where timing is everything.

6. Customizing Your View: Labels, Constellations, and Atmosphere

Stellarium lets you customize virtually every aspect of the display. Here are the most useful toggles for learning the sky.

Experiment with these toggles to find the combination that works best for your learning style. Most experienced users keep constellation lines on and atmosphere off while planning, then switch to a clean, realistic view during actual observing.

7. Plugins: Telescope Control, Eyepiece View, and More

One of Stellarium's most powerful features is its plugin system. While there are dozens of community plugins, the two that matter most for amateur observers are bundled with the desktop program.

Telescope Control Plugin

Stellarium can control GoTo telescopes via the ASCOM platform (Windows) or INDI (Linux/Mac). This means you can select an object in Stellarium and have your telescope automatically slew to it. To enable this: go to Configuration (F2) > Plugins > Telescope Control > Configure > add your telescope. The plugin supports Celestron NexStar, Meade LX200, Sky-Watcher SynScan, and many other common mounts. This eliminates the need for a separate hand controller for star-hopping and lets you plan your entire session from one screen.

Eyepiece View Plugin

This plugin shows you exactly what your selected object will look like through a given eyepiece on a given telescope. You can specify your telescope's aperture, focal length, and eyepiece focal length, and Stellarium will render the field of view — including star magnitudes, orientation, and approximate brightness. This is incredibly useful for confirming that an object will actually fit in your field of view and look as you expect.

Other Notable Plugins

• Satellites Plugin — Displays real-time positions of ISS, Starlink, and thousands of other satellites. Includes predicted brightness and pass times.
• Solar System Editor Plugin — Adds comets, asteroids, and minor planets to the simulation. Essential for tracking events like asteroid Vesta at opposition.
• Scenery Plugin — Allows you to import a 360° horizon panorama of your actual observing site for the most realistic simulation possible.

8. Stellarium Mobile: Using the App in the Field

While the desktop version is best for planning, the mobile version is designed for use at the telescope. Here is what you need to know.

Point your phone at the sky. The mobile app uses your phone's gyroscope and compass to show you exactly what you are looking at in real time. Hold your phone up, and the sky chart moves with you. This "live view" mode is remarkable for identifying what that bright star or planet is — just point and the label appears.

Search and night mode. The mobile app includes the same powerful search as the desktop version. Before you head outside, plan your target list on the desktop and sync it. Once outside, set your phone to night mode (red screen) to preserve your dark adaptation. The app's red-screen mode is one of the best among astronomy apps.

Stellarium Mobile Plus adds three features worth the upgrade: (1) deep-sky object images that show you what an object looks like before you find it; (2) telescope control so you can slew your GoTo mount from the phone; (3) offline star charts, so you do not need mobile data at a dark site.

For a comparison of Stellarium against other stargazing apps, see our best astronomy apps guide.

9. Pro Tips for Better Stellarium Use

Frequently Asked Questions About Stellarium

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