It can be quite difficult to know where to start when you see the sheer amount of astronomy apps out there. From judging if the weather’s good enough to observe to figuring out whether something is a star or a planet, we’ve identified a selection of free apps that should cover all of your stargazing needs.
1. Weather Underground
Weather Underground is a free weather app which provides accurate and data-rich forecasts. In contrast to other apps, it leverages local and personal weather stations to make forecasts, giving it an advantage in accuracy.
2. Clear Outside
This is an app specifically made for astronomical weather forecasts. Whilst also data-rich, it focuses primarily on astro-specific weather, like cloud cover and humidity. In addition to this, lunar phase, sunrise and sunset times, and ISS passes are present in the forecast, making it a great way to plan a night under the stars.
3. AuroraWatch UK
This is a very intuitive and simple app for assessing the chance of seeing aurorae in the UK. It provides both quantitative data and a ‘traffic light’ system which makes it easy to interpret at a glance, and push notifications are sent at times of high activity, meaning you’ll never miss a chance to see the Northern Lights in the UK again – highly recommended!
4. Celestron SkyPortal
This is easily the best planetarium app on mobile. Among its many features, there is a guide to “Tonight’s Best” objects to observe; detailed information and live positions of planets, moons, asteroids and satellites; plus an audio guide to the constellations and major astronomical objects. By turning on “night mode” and compass, you can point your device at the sky to find objects without ruining your night vision. It helps to have some basic astronomy knowledge to get the most out of this app, but it’s difficult to find anything better.
5. SkyView Free
This is the perfect app for newcomers to astronomy. Augmented reality mode allows you to use your phone camera to point at any bright star, planet or moon and learn about its properties and mythology. It gives just enough content to be interesting, but not enough to overwhelm users.
6. Sputnik! – iPhone only
An excellent app for predicting ISS passes and Iridium flares over the coming week – ideal for light polluted skies where fainter satellites are easy to miss. It has a clean UI, providing information on where to look and the expected brightness, along with the option to set reminders.
7. ISS Spotter – iPhone only
This is a simple yet effective app for tracking the live location of the ISS. It gives info on upcoming visible passes, with helpful diagrams, and allows you to set reminders. However, it’s not useful for spotting other satellites or Iridium flares.
8. Heavens Above – Android only
An incredibly rich and full-featured app. Contains a huge catalogue of many different satellite types with information about almost everything – perfect for the more advanced observer. The UI is somewhat clunky and the sheer number of satellites may be overwhelming, but these flaws are quite minor compared to the overall scale and quality of the app.