While many apps are designed to help organize your life or simply pass the time, a number also seek to bring the glory of the cosmos into the palm of your hand. Here's a list of 10 standout astronomy and skywatching apps that can help expand your universe.
NASA App (free; iOS and Android)
The NASA App (Android, iOS) serves as a gateway to the latest news from the world's premier space agency. The app provides access to a huge amount of information about NASA, its many missions and the cosmos, delivered via feature stories, photos, videos, live webcasts and more.
Space Images (free; iOS and Android)
Space Images (Android, iOS) is developed by NASA's Jet Propulsion Laboratory in Pasadena, Calif., the agency's go-to center for the robotic exploration of worlds beyond Earth. As its name suggests, the app delivers jaw-dropping photos of planets, moons, galaxies and more, along with informative captions. You can store these images on your phone or tablet as backgrounds and wallpapers.
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Exoplanet (free; iOS)
This free app from astrophysicist Hanno Rein lets you keep tabs on the study of alien planets, one of the most intriguing and exciting branches of space science out there. Exoplanet is an interactive, frequently updated catalogue of all known alien worlds, the official tally of which is now approaching 900.
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Planets (free; iOS and Android)
Planets (Android,iOS) sticks a little closer to home than Exoplanet, providing an annotated, 3D guide to the worlds in our own solar system. This free skywatching app, which has been downloaded more than 8 million times, shows you how to spot planets in the night sky from wherever you (and your mobile device) happen to be.
Sky Safari 3 ($2.99; iOS and Android)
Sky Safari 3 is a great skywatching app that helps users identify planets, stars and constellations, featuring photos of the solar system's major planets and moons taken by spacecraft. The basic version of Sky Safari 3 (Android, iOS) has a database of 46,000 stars and 220 star clusters, nebulae and galaxies; these numbers go up dramatically if you splurge on the Plus ($14.99, Android, iOS) or Pro ($39.99, Android, iOS) versions.
Satellite Flybys ($2.99; iOS and Android)
If you're interested in spotting man-made objects in the night sky, then Satellite Flybys (Android, iOS) is a good choice. This app lets you know when interesting craft such as the International Space Station and NASA's Hubble Space Telescope will be overhead, and it tells you where to look.
NASA Space Weather Media Viewer (free; iOS and Android)
The sun gives us life, but its massive eruptions can wreak havoc with radio communications, GPS navigation and power grids. Keep an eye on the beautiful, complex and ever-changing solar surface with NASA Space Weather Media Viewer (Android, iOS), which provides views of the sun from a variety of NASA missions in near real time.
Mars Globe (free, version with HD 99 cents; iOS)
Ever wondered where exactly Mars' enormous mountain Olympus Mons is, or whether NASA's rovers Curiosity and Opportunity could meet up on the Red Planet? You can learn basic Martian geography with Mars Globe, which takes users on a virtual tour of the Red Planet from above.
Moon Phase Pro (99 cents; Android)
Moon Phase Pro lets you track the ever-shifting visage of Earth's natural satellite, providing up-to-date information about the moon's phases and its rise and set times. The app's sharp view of the moon is highly interactive, allowing users to manually shift its phases or see what it looks like in the night sky from the other side of the world.
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Galaxy Collider (99 cents; iOS)
In about 4 billion years, our own Milky Way will crash head-on into the nearby Andromeda galaxy, eventually creating a new, hybrid megagalaxy. You can simulate this and other monster smashups with the Galaxy Collider app, which also allows you to customize collisions by tweaking star numbers, masses and other parameters.
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