With the help of night-sky apps, you can take your astronomy hobby to the next level and deepen your understanding and appreciation of the universe. Here I look at 10 popular apps for exploring the night sky.
As a backyard astronomer, I find, apart from using hardcopy sky maps and a planisphere, having a relevant app or two enhances the whole stargazing experience by helping to identify and find stars, planets, constellations, and Messier Objects, at the time you want.
With them, you can plan your observing sessions, corresponding to weather conditions and sunset and moonrise times.
Some apps simulate the night sky, allowing you to explore the cosmos from the comfort of your home.
You can even find the International Space Station (ISS) and see the floating space junk. You can easily do this with just a few taps on your phone.
Here are 10 popular apps for backyard astronomers, starting with my current favourite:
- Sky Guide
- Star Walk 2
- Stellarium Mobile Sky Map
- Night Sky
- GoSkyWatch Planetarium
- NASA App
- Distant Suns
They all offer similar features and can help expand your experience of the night sky. It can purely come down to your preferences for things that determines which one is for you. But it’s worth knowing the breadth on offer to assist you when naked-eye stargazing or exploring the night sky with binoculars or your telescope.
If you’re looking for an app to get yourself ready for meteor showers, there’s MeteorActive that’s free on the App Store. For apps that cover more, read on…
I use Sky Guide mostly. Why? Because it’s simple. It’s not clunky like others that can be slow to load. It offers all I need at my fingertips. It also happens to be the Editors Choice on the Apple store.
What to like about Sky Guide astronomy app:
- Augmented reality that you can easily switch on or off
- The app’s easy to use user interface
- You can use an interactive map to set location
- A wealth of information about celestial objects
- Uses local weather data
- Has built in compass
- Time-lapse feature
- Night mode helps with what you need for dark adapted vision
- Pro version offers fields of view, imaging calculator, and coordinates.
- Can function without internet access
- Can set manual location for devices without GPS
Users can access the app even when they don’t have internet connectivity.
The app’s cons like others is that it can drain battery life if the signal is too weak to accurately determine your location. Manual settings can help.
The Sky Guide app is a stargazing app developed by Fifth Star Labs LLC. According to a report from 2019, the app had over 10 million downloads. The app has a free version and subscription versions with pro features. It also offers in-app purchases. It’s available on both the App Store and Google Play Store.
Like most of these apps, SkyView uses augmented reality (AR). You simply point your phone’s camera at the sky and identify stars, constellations, planets, the ISS, satellites, and more.
What to like:
- Shows paths of an object across the sky to locate it on any date or time
- Get alerts for celestial events
- Has night mode to help with night vision
- It provides detailed information and trivia about the objects you are observing
- WiFi not needed. Functions without a data signal or GPS
- Has a time-lapse feature that lets you see how the sky changes over time, from past to future
It has background music as a default. If you’re like me you’ll want to mute this.
The app was developed by Terminal Eleven LLC, a software development company based in the United States. As of 2023, SkyView has been downloaded over 3.2 million times and SkyView Lite 40 million times worldwide on the Apple app store.
SkyView Lite has fewer listed sky objects compared to the full version.
SkyView Lite and SkyView are available for free on both iOS and Android platforms. There are in-app purchases for additional features in both.
Star Walk 2
Star Walk 2 has an extensive database that includes information on constellations, planets, and satellites. Similar to others mentioned, it does not require internet connection.
It also uses AR for an immersive experience.
This app has a lot to offer, but I found it takes a while to load.
Some users have reported occasional glitches and inaccuracies in the app’s star maps, and some features require a paid subscription. Nonetheless, Star Walk 2 remains a popular and useful tool for stargazing enthusiasts.
Star Walk 2 was developed by Vito Technology. As of 2022, it has over 500k downloads on the Google Play store. The app has in-app purchases.
- Has a what’s visible tonight area — for upcoming celestial events
- 3D models of constellations, allowing you to explore them from any angle.
- Offers “Time Machine”, a feature showing how the sky looked past, present, or future
Stellarium Mobile Sky Map
Stellarium Mobile – Sky Map has features of a star catalog, constellation illustrations, and the ability to zoom in and out.
Stellarium.org is known for free open source astronomy software that simulates looking at the night sky through binoculars or a telescope. It’s a great learning tool. It requires a lot of RAM.
This app is a much cut down version for a mobile device.
One of the pros of the app is its user-friendly interface, making it easy for beginners to use.
Clicking on a sky object in the AR will give you information from Wikipedia relevant to that particular celestial body.
The Stellarium Mobile Sky Map was developed by Noctua Software and has been downloaded by over 10M+ users on the Google Play Store.
The app has in-app purchases either as a monthly subscription or as a one-time payment. The free version has limited offerings.
The downside is the free version is limited in what it offers.
The paid version unlocks features such as the calendar, observing tools such as 3D view and visibility, and other advanced options in the settings.
What to like about Stellarium Mobile Sky Map:
- The free version includes ‘sky cultures’, a feature where you can turn on knowledge from one nation peoples around the world
- It has auto-location but you can also input coordinates manually
- It loads reasonably fast and has a simple user interface
- Supports night vision, planning observing sessions and more in the paid version
- Paid version as one off payment is a small amount
The Night Sky app also includes features you find in apps already mentioned such as AR and ‘time machine’.
Some users may find the app’s premium features to be costly or unnecessary.
The Night Sky app was developed by iCandi Apps and is available for free download on Apple devices. Not on Google Play as of this date.
It is free with option Night Sky+ available for a yearly or monthly subscription.
What to like:
- Can add personal tags to the sky map for future reference
- Connect with others when using it on macOS 12.1 or later
- Map the Aurora
- Tap to see the planets in regard to their internal structures
- The app also includes a library of educational articles and videos about astronomy
One of the main advantages of using Sky Safari is its extensive database, which includes over 2.5 million stars, planets, and other objects. The app also provides detailed information on each object, including its distance from Earth, magnitude, and other important characteristics.
This is a paid app with in-app purchases on the Apple app store. The Pro version offers more features including support for telescope connection at a much higher price.
On the Google Play you get to choose from a number of variants, the cheapest — SkySafari Astronomy has only 100+ downloads. SkySafari 6 Plus has the most downloads, 10K+.
The Sky Safari app has been developed by Simulation Curriculum Corp.
This is a paid app with in-app purchases.
What it offers:
- Can see other users — how many are viewing a certain object
- Features include what’s visible tonight
- 3D views
- Has a helper for pronunciation of those tricky constellation and star names
- You can watch an eclipse with the ‘time machine’ feature
- Spectacular graphics in showing animated events such as meteor showers
- Premium subscription offering “massive deep sky database, events, curated news and articles, connected stargazing features, light pollution map and more”.
The GoSkyWatch Planetarium app is easy to use. It offers a ton of information at your fingertips by just pointing at the sky and tapping.
It’s developed by GoSoftWorks and is a paid app on the Apple app store only — not available for Android.
What to like:
- 3D interactive planets
- Has wide zoom range
- Wikipedia links to more information
- The app also includes a red light mode to preserve night vision and a night mode that switches the entire app to a dark theme for comfortable stargazing.
The NASA app is an educational tool but also a virtual planetarium. It provides information about upcoming celestial events such as meteor showers, eclipses, and more.
One of the best things about this app is that it’s free to download and use. It is available on both the App Store and Google Play Store. There are no in-app purchases that limit it’s use to a basic layer of information. It’s recommended for years 4+.
The NASA app was developed by NASA’s Communications and Education divisions. On Google Play the app has been downloaded over 10 million times. More information about it can be found on the official NASA website.
Redshift offers super cool apps for backyard astronomers on both Google Play and the Apple app store.
Redshift is developed by the Austrian company, “USM”. The free variant “The Sky by Redshift: Astronomy has been downloaded more than 50K times on Google Play Store.
The Redshift Sky Pro app is not free. It requires a one-time payment of $9.99 (as of April 2023) and includes in-app purchases.
You can also get a professional subscription to support telescope control. Redshift Sky Ultimate is the extended app for this.
- Redshift extended app has a database of over 2.5 M stars + online access to 1B more and 70K deep-sky objects
- Sky calendar and visibility data
- Control support for Meade or Celestron telescopes (apart from Nexstar evolution)
Distant Suns is a mobile app developed by Mike Smithwick. The app has been downloaded over 1K times on the Google Play store. It is a paid app on both the App Store and Google Play.
More info at DistantSuns website.
What’s to like:
- No internet required
- 18 million stars
- Integrates with NASA’s Night Sky network for US users
- Descriptive stories for each constellation
- Daily updates on weather patterns
- A tap of the virtual sky and you have the hidden data of each object
Helpful tips in using apps
In general, these apps require access to your device’s camera. Some can work without GPS or internet connection.
In some, you may benefit from switching on the Compass Calibration on your device for the augmented reality feature to function properly.
Wi-Fi is not always as reliable as mobile data in picking up location. You can try to manually set location.
Overall, using apps as a backyard astronomer has helped me to learn more about the night sky and to make the most of my time spent observing.