Discover the Secrets of Our Night Sky With SkySafari

Outer space is big. From our vantage point, it’s mostly just dots in the sky that we see at night. But there are billions of stars, asteroids, comets, and planets out there. You can see of them when you look up on a clear night, more if you use a telescope, and more still if you use SkySafari, an app that shows 46,000 stars and many of the best-known galaxies and nebulae with images from NASA and other expert star-gazers.

SkySafari isn’t the prettiest app around, but it more than makes up for it with the majesty of the stars and reams of encyclopedic information. It’s deep enough that serious astronomers can use it as a reference tool, and suitable for the rest of us to explore and learn about outer space.

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In-Depth Astronomy

When I reviewed Cosmographia earlier this year, I noted with some disappointment that for all its beauty and supposed accuracy there was very little information available in the app. You could marvel at the majesty of our solar system, but you couldn’t learn much from, or about, it.

SkySafari takes the opposite approach; it’s packed with detailed descriptions and data about thousands of objects — stars, planets, constellations, asteroids, and more. But it offers an unwieldy, comparatively ugly interface that makes it hard to explore without either clicking things at random or knowing precisely what you want to look at.

SkySafari doesn’t have the best interface around, but it does the job.

A few tweaks will turn your field of view into something prettier.

If random clicking is your modus operandi, however, you’ll have a splendid time learning about the known objects in the universe. Zoom out and crank up the settings for number of stars and deep space objects to display, and you’ll be hard-pressed to not click on something. The universe may be infinitely huge and mostly empty, but when you compress it all down to a small 2D plane it’s hard to find the darkness.

If you’d rather not click randomly, and you don’t have good enough knowledge to search for objects by name, there is one other option — but it’s not immediately obvious. The Search menu (that’s the one in the menubar, not the box in the top-right corner) can be used for quick access to objects and planetary bodies in 14 categories — Tonight’s Best plus the 13 types of object included.

It may seem like everything is in that toolbar at the top, but some functionality is only present via the menubar.

Double-click or right-click and select Object Info to bring up the info pane. For most objects this is just whatever technical information is known — such as celestial coordinates, temperature range, luminosity, diameter, visibility, and so on. But many — we’re talking in the hundreds — also offer written descriptions about their properties, discovery, history, and significance to us humans. The description for a star called Altair, in the Alpha Aquilae galaxy, for instance, includes trivia about the meaning of its name (the flying eagle) and use in a science-fiction film, along with five paragraphs contextualizing its place in relation to us.

There’s lots of information, even about less popular stars.

Better known objects — like, say, Mars — include long, detailed descriptions, which are both interesting and highly-readable, and images. Unfortunately, the images are low-resolution, which means they look blurry when enlarged. Still, you get a feel for the painstaking research that must have gone into creating the app. You’ll walk away from SkySafari knowing much more about astronomy than you did to begin with.

Going in close on Mars, you can look at the surface detail while reading an in-depth description about its history, properties, and significance to human culture.

Over the Horizon

SkySafari’s default view has you looking up to the sky from a specified point on the Earth. You can choose different latitude and longitude coordinates, and alter the date and time. The Horizon menu lets you toggle elements of the Earth’s atmosphere and land mass — the horizon, sky, daylight, and an overlay image. The view is beautiful, if a little odd (thanks to a wide-angle lens).

You can customize the field of view and appearance of constellations, as well as the overlay image (which can be disabled entirely). There’s also accurate data over thousands of years.

You can zoom and pan as though looking through a telescope, but unlike a real telescope SkySafari lets you change the color intensity of stars, see the names of stars and constellations, marvel at filled-in visuals of the constellations, and lookup information about any object you see. Each of the buttons at the top of the window brings up a bunch of settings that add or remove information or tweak the general appearance of the display.

No matter what you’re looking at, however, or how much you zoom in or out, you’ll be looking at it from the perspective of our home planet. You can turn the horizon and sky off completely, so that it looks like you’re floating in space, but you’re still going to be floating about a relatively fixed point. That’s okay — this is an astronomy app, not a space flight simulator — but keep in mind that you won’t be getting any glorious shots looking back at the blue marble that we call home.

You can, however, try to display the names of every object included in the app’s charts.

You can, however, try to display the names of every object included in the app’s charts, along with guidelines and color assists. It looks a little something like this when you do.

There’s not much surface detail anywhere in SkySafari, actually. Neighboring planets get a texture applied to their service, if you zoom right up close, but everything else is just a colored ball with a bit of a glow.

You Spin Me Right Round

You can travel forward or backward through time at whatever speed you like, either in incremental steps or one big jump. It has a hypnotic beauty to it when you turn on the animation, sit back, and watch the seconds, days, months, and years tick by. Your view rotates and moves through space in conjunction with the Earth, proving a 360 degree tour of the heavens. (Keep in mind that certain settings result in repeated disorienting jumps in perspective, though — so you may need to experiment here.)

SkySafari has everything I wished Cosmographia would include, minus all the things that make that app great to play around with. It has much better bang for its buck — you’ll have every reason to keep coming back after an evening, to learn more about the stars that dot the sky — but none of the style and flair you need to really make the subject engaging to newcomers.

It doesn;’t compare well visually with Cosmographia.

Compare it to the sleek lines and gorgeous visuals of Cosmographia (pictured), and SkySafari’s presentation seems woefully inadequate — even if its depth is top-notch.

A Dwarf Star

SkySafari shines, but not as brightly as it could. The interface is fluid and responsive, as the developers claim on the app listing, but it’s badly organized, unnecessarily complicated, and beginning to look rather dated in the face of the sleek minimalism on show elsewhere. All that extra information comes with a higher barrier to entry, and SkySafari will likely confuse and confound many astronomy or computer novices.

My search for the perfect (non-expert-level) astronomy app continues unabated. It would contain the best bits of Cosmographia, SkySafari, and Solar Walk (which we reviewed in November), together with some features I probably haven’t thought of, and I would rave about it to everyone.

For now, the state of astronomy apps on the Mac is thus: Solar Walk is a great beginner’s guide and educational tool. Cosmographia will get you excited about our solar system with its stellar 3D recreation, but it’s light on the explanation and documentation side of things. Both show little more than the planets and key satellites in our Solar System, however. SkySafari shows much more detail, but with an inferior interface, from any place on Earth (rather than as a floating body in space). There’s also Redshift, SkyORB, and several others that I haven’t yet tried. If you have any suggestions or requests, please let us know in the comments.

Hardcore astronomy buffs can always step up to SkySafari Pro ($49.99), which boasts wired or wireless telescope controls and a massive data set including 15.3 million stars, while casual astronomers looking to step up can take the intermediary option SkySafari Plus ($19.99), which offers 2.5 million stars (20 times the number in the basic version) along with telescope control. If you want to learn more about space, you could do a lot worse.


SkySafari offers a detailed star chart and guide to astronomy, with tens of thousands of objects, in-depth descriptions, images from NASA, time travel, and ample customization. Its interface and presentation trails the competition, but SkySafari shines as one of the most comprehensive astronomy apps on the market.