MICHAEL A.  For any people who have ever found that jumping around to different places in Google Earth was an addictive adventure, this is even better...  
(Version 1.5)

ENRICO NENCINI  Awesome software. AND free. Tested on PPC and Intel (leopard): works seamlessly.  
(Version 1.5)

JAZZJOHANNES  Brilliant, I love the complete StarTrek TNG add-on.  
(Version 1.5)

TICE  This app is great. I used it since the early days and it still gets me. Wonderful work. Only the navigation could be more intuitive (i.e. the arrows left and right could change the direction instead of turning and up and down shouldn't be opposite).

Anyway, thanks for this great piece of freeware! : )  
(Version 1.5)

VERSANICK  First, let me reccomend this to anyone with an interest in Astronomy, or who is taking in Astronomy-related class somewhere (I sure wish I had this years ago when I was taking Astronomy in college).

Now, an amazing 3-dimensional adventure through the solar system and much more. To this minute, I've been through mostly the entire Milky Way, and I don't even know how far this program maps. This is amazing.

Very easy to learn how to navigate around. Drag around with the mouse, or use your arrow keys, travel at 100 m/sec or 100 times the speed of light, or on the scale of astronomical units per second (1 AU is the distance from earth to sun)... impressive, easy to turn on/off labels of orbits, planets, constellations, and much more (all easy to find in Preferences). You can even see cities, mountains, and other things, all at the click of the mouse.

Great choices of rendering paths (for graphics) from Basic to OpenGL 2.0, and many things in between (which will work better with different video cards, old and new). It will even tell you (in most cases) if you cannot use the selected rendering option. There's something for anyone. Beautiful graphics. I suggest that you see for yourself. It's hard to describe the fact that I can see almost every detail of the moon, as deeply as I've ever studied its surface. Very, very impressive on my 19" monitor on my G5 tower.

There's even a 'Favorites' menu (akin to Bookmarks). Zoom from planet to start to constellation in seconds. There is so much you can do with this program. Or just leisurely show your friends what a cool program you found.

I highly suggest this for anyone _teaching_ astronomy as a professor or teacher. Chris Laurel, and anyone else involved in developing this deserves credit for the most impressive and comprehensive (yet simple in nature) space exploration app I've seen that is so easy to use, even a relative computer novice can tool around.

And free. Props. I honestly can't say anything negative. Congrats on an amazing app. I wish I found this a long time ago.  
(Version 1.4.1)

SELF-INFLICTED  Wow. Seriously... wow.

Space is big. No, bigger than you're thinking. Really, really, mind-bogglingly big. Wow.

Easy to get lost in, too -- in time as well as space. I've lost track of how many hours I've spent tonight cruising the cosmos.

This is really an amazing visualization tool. It's not as if I need it in my daily work, but I sure like having it to escape to.  
(Version 1.4.1)

APPLECRYPT MODS  incredible - i love this s/w!!!

thank you :)  
(Version 1.4.1)

ANONYMOUS  At least one fan hopes for an update with:

-toggle on/off full screen

-the tenth planet!

-solar system guide (wide view of orbits)

-satellite mission guides with links to nasa pics

Thank you for a brilliant program, Celestia is the bomb.  
(Version 1.3.2)

ANCIENTYGER  a pre-release of 1.4x it has some issues (i've not seen them...) but, seems to work well on a mini.

http://shatters.net/forum/viewtopic.php?t=7457

please, follow the forums and post there show your support for the mac version, but know that it is under development and hasn't been ignored.

This, is some great software!  
(Version 1.3.2)

ANONYMOUS  Celsetia worked fine on my G3 iBook when running 10.2. But on my G4 iBook running 10.3 it crashes the whole system.

And I did do everything the ReadMe file says.  
(Version 1.3.2)

ANONYMOUS  Celestia continues to be great. on my "old" G4 466 with a 16MB ATI Rage Pro it performs well enough to prompt me to buy a new video card ;-P I've been following the progress of Celestia for a while now, The Mac OSX version still does not match the Windows version, but i know poeple are working on it. I wish more mac developers would help this opensource project along.   
(Version 1.3.2)

ARYUGAETU  I have a 15"FP 800Mhz iMac w/ OS 10.3.7 and it works fine. I placed the entire contents of the virtual disk into a new folder on my desktop, labeled the folder "Celestia", and then placed the folder into my Applications folder. Perhaps people are dragging just the application into their hard drive and are not taking the "CelestiaResources" folder, too. The makers of Celestia need to place everything into a single folder so upon decompressing, the user can just drag the whole folder into the hard drive.

For a FREE application, it is well worth the price. It is great for beginners in astronomy. My only recommendations would be to add color to the stars, use real images of the galaxies and add more of them, because the overall look of the sky isn't real at all. This is its major fault. As a purely scientific aid, it is fine  
(Version 1.3.2)

ANONYMOUS  My eMac was frozen too with this version (1.3.2) and the old worked. Trash until the next one !  
(Version 1.3.2)

PFFFT!  This app has always worked well for me, lots of fun. It does require a lot of system resources, not surprising for what it is.  
(Version 1.3.2)

3818  Use wit caution! Causes a system-wide freeze on my new eMac! After 3 tries, I trashed it!  
(Version 1.3.2)

ANONYMOUS  Still a very fun toy on my G4 PowerBook, but I wish it would use less CPU.  
(Version 1.3.2)

ANONYMOUS  Crashed hard on startup on a Dual 1.25 G4 with 2 GB RAM running 10.3.6.  
(Version 1.3.2)

SCHMELDING  Celestia, will you marry me?  
(Version 1.3.2)

DAVID  This program has huge potential. The package you download is only the beginning, you can have as many as 2.5 million stars that you can visit and the better your system the better and more realistic it gets.

You might think that earth is rendered excellently in the original download, but this is only 2k texture and depending upon your graphics card you can have up to 64k texture which is a hell of a lot of detail. You can even create your own bits to add-on to the program e.g. a nebula.

There is a forum in which you can ask questions and they will be answered within a day. You can talk about the universe and science in general or the program itself. There is a great site which you can get extra downloads and additional info at www.celestiamotherlode.net

I can only see this program getting better  
(Version 1.3.1)

ANONYMOUS  Cool little program! Try moving pretty far out from the sun and then flying towards it at 15 times the speed of light.. Amazing how long it takes for the sun to get big!

Discover magazine had an article about this program in the November 2004 issue which is how I found it. Well worth trying out and playing with. Since it was originally written by an ex Microsoft employee, it's nice to see that it runs well on Mac OS X.  
(Version 1.3.1)

UMAROMC  sourceforge DL URL:

http://prdownloads.sourceforge.net/celestia/celestia-osx-1.3.1-1.dmg?download  
(Version 1.3.1)

A MARTIN  The Mac version has (like with most Mac apps) a more spartan set of features than the Windows and Linux versions, but it's still an impressive program.

Wish it had the same features as for the other two platforms, though...  
(Version 1.3.1)

HEILIGER  Amazing! What a great app posing as freeware!

All in a lunch break, I managed to coast over Io's surface as I watched the sun and earth appear over the horizon... I increased speed and reached Earth in seconds... and glided into the atmosphere (flying over the green and blue texture of Earth with blue sky overhead). I soon decided to fly up to the moon... and as I neared it, I noticed a small speck floating over the surface... as I got closer, I was able to click on the 'speck' to see what it was. It was the Apollo 11 Command Module! So, in real-time, I was able to fly up to a fully-rendered derelict Apollo 11 CM, complete with U.S. flag decals and multi-directional thrusters... a fun little easter egg.

Sure, there are minor bugs (trying to 'straighten out' your view after locking or tracking an item, hitting C to center on a target and occasionally being warped twelve kazillion light years from anything), but these little glitches are rare and unintrusive.

Celestia is real-time scientific accuracy with the simplistic controls of a video game. Perfect for hobbyist astronomers like myself. Rock on Chris.  
(Version 1.3.1)

ANN  What a trip! Pack a lunch because you'll be gone a while. This was fun and educational.  
(Version 1.3.1)

ANONYMOUS  WOW, Just WOW... This is an amazing program. One tiny thing though, sometimes, it seems it gets caught up in some wierd situation where the whole screen is black, even when I select sol and tell it to go there, it never actually arrives.. it's always some 300 billion ly away..   
(Version 1.3.1)

CHRIS  Ditto on all positive said. I first freaked out when I backed out of the Universe and looked back. Awesome! I've used it since the early days and this version is great.

Now if anyone can help me setup my iShock II so I can blast around with a joystick......  
(Version 1.3.1)

WZRDJR  Looks great. Renders fast. Fantastic for education or just exploring the neighborhood, er...universe. Abolsutely wonderful. If it wasn't free I would pay for it.  
(Version 1.2.5)

ANONYMOUS  Quality app. Excellent!  
(Version 1.2.5)

ANONYMOUS  The best space simulator ever made !  
(Version 1.2.2)

MACMAN X  Great for the price(free).  
(Version 1.2.2)