Universe Explorer

excellent
key review info
application features
  • Exponential zoom feature
  • (6 more, see all...)

I guess you're familiar with the big blue ball we're all living on. It is called Earth and as big as it may seem to us, it is just a tiny fragment of a greater design, the Universe. But I am sure that you know all this and a bit more. And if you don't, take a trip to the nearest Planetarium and learn some very interesting things about it.

Or better yet, take the time to download Celestia, a free real-time space simulator that provides a three dimensional experience of our bit of Universe. Celestia places you in the virtual reality of Milky Way galaxy allowing close view of the neighboring planets and their orbiting around the Sun.

The greatest thing about Celestia is that you're not confined to Earth's surface and you can take a look at Pluto and its two moons or watch Saturn with its imposing rings. Or to Venus, Mars, and even the Sun. You can adjust the orbiting speed and watch how exactly the planets are rounding the venter of our little universe.

The interface is one giant view of the galaxy, with stars scattered everywhere and planets orbiting around the Sun. When launching the software everything seems nice and calm, but actually, everything is moving. The activity is not visible because it is rendered in real-time. But as soon as you press key a few times everything starts moving. That is why, depending on the moment when you launch the application, the Earth will be in a different position.

The application is actually a personal planetarium which you can navigate any way you want. And above all things, it is filled with bits of information on every star of the galaxy (distance from your viewpoint to the selected celestial body, luminosity, class it belongs to, surface temperature, diameter etc.). The downside is that it does not make available additional details like the name of the astronomer who discovered it, but the database is already immense (I traveled all the way and could not find a star, planet or galaxy without a name and some of the aforementioned details).

To tell you the truth, there aren't too many options available, but those at hand are a hell of a helper. File menu for instance, allows you to capture the displayed images and even videos of your space travels. The entire navigation between stars and planets is entirely controlled by your mouse and keyboard, from changing the point of view to going to a certain star or satellite.

In the left upper corner of the screen, there is information about the selected object while in the lower left hand corner there is the speed of your travel. If this is zero on the line it means that you are moving in real-time and nothing seems to be changing.

Navigation menu located in the top left part of the application window is particularly interesting as it contains lots of useful options. Here you can access the Tour Guide, a window providing you with information on various celestial bodies (planets, star clusters, star systems) like Jupiter, Pluto and Charon, Eros, Alpha Centauri, Pleiads, Hyades, 51 Peg b (the first planet discovered orbiting a normal star other than our Sun) etc. Unfortunately, there aren't too many bodies in the list.

If you are a beginner in Solar System browsing (as I am) you can use the Solar System Browser under Navigate menu and visit all the planets in our galaxy and their satellites as well as asteroids and celestial body formations. To get more information on a certain body, you can access the context menu and choose Info option which will automatically open a page in the default web browser giving more details then Celestia. Star Browser does exactly the same thing but limits its database to stars.

As any respectable software, Celestia is equipped with an options menu that allows you to enable the view of various elements on the screen. You can see Earth atmosphere, celestial grid, clouds, comet tails, constellation borders, constellations, eclipse shadows, galaxies, nebulae, orbits, planets, ring shadows, stars, markers for the selected elements, asteroids, comets, moons or spacecrafts. Practically, you can see everything there is to see in our galaxy and more.

The downside is that the images are not as detailed as one would expect them to be (at least in this version) and looking at Saturn's asteroid rings is not unfamiliar to what you've been seen on TV or in geography books. I would have liked to navigate among the asteroids and everything there.

But there may be a possibility to do just that, as the program supports add-ons and there is quite a prolific community behind it. If you were to install all the add-ons, you would need at least 8GB of space on your hard disk. From what I have seen, there are various representations of the celestial bodies (I changed the Sun as the original Celestia reproduction did not seem too real).

At a first glance, the application does not seem to provide too many options, but taking the time to check out its manual on Celestia add on repository website or if you take a look in help menu under Controls, you will be showed different.

There are myriads of shortcuts that the application provides and I do not think that there is a key on the keyboard that does nothing in this program. I suggest you take a look at them as they truly enrich Celestia experience. Not only will you be able to split the screen into multiple views (both vertical and horizontal), toggle planets orbits or galaxy rendering, but you will also be able to apply the corresponding textures for the different objects in view.

If you find special stars or objects in the sky and want to return to them from time to time, you can create bookmarks for those locations. These can be neatly organized in folders depending on importance or your interest. This way you can find what you are looking for with no trouble at all.

The Good

The application is absolutely free and provides precious information on our piece of Universe and more. It makes available details directly from the Dictionary of Nomenclature of Celestial Objects.

Navigating among planets, asteroids, moons and other celestial objects is extremely easy and the 3D perspective only adds to its value, because you can change the point of view the way you like it.

With the aid of specific add-ons you can enrich Celestia experience and enjoy more realistic pictures as well as information on the various objects.

The Bad

There is no proper Help file, only a list of keyboard shortcuts with no additional explanation. It is not a big deal, but a rookie will find it quite difficult to recall all those shortcuts.

Celestia's menu does not list even a third of its entire suite of options. There isn't too much information about the more important elements of the galaxy.

The Truth

Despite the slight discomfort in using it for lack of a proper manual, Celestia is a hell of an educational software. Maybe the images are not as realistic as you'd wish, but every star you see has a name and a web link to more information.

You can "see" the planets moving in real-time or speed up their movement for a better understanding of the process.

Truly amazing application. The community working on add-ons is also "guilty" of this success (I downloaded an add-on for the Sun which displayed even the black spots).

Here are some snapshots of the application in action:

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user interface 5
features 4
ease of use 4
pricing / value 5


final rating 5
Editor's review
excellent