I agree with Doodler that the definition of 'great' matter a lot in terms of producing an answer here.

To me the answer is either Blade Runner or 2001 depending on what you're measuring greatness by.

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hmmm 0% for Close Encounters--gee! Well, it was a good entertaining movie, if a bit strange. I bet it inspired a lot of kids to play with their mashed potatoes, anyway.

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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

Quidquid latine dictum sit, altum sonatur.

personal page: http://blog.astrosketches.info

I had to hit the Blade Runner button. I liked 2001 on paper and it did translate to film better than DADOES, but the imagery was much better in Blade Runner.

Solfe

Tough call for me. Star Wars (though arguably not SF) because of what it did for the genre in general? 2001 for the accurate special effects and how it makes you think? Blade Runner well, just because (not to mention the great soundtrack)?

I'm voting for 2001.

I'd call Star Wars SF, just not hard SF. With some fantasy elements, of course!

After all, there are swords and sorcery, of sorts.

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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

Quidquid latine dictum sit, altum sonatur.

personal page: http://blog.astrosketches.info

Play with them? That would require not eating them as soon as they're served!

(Yes, I love mashed potatoes.)

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Although I picked one vote, I actually like each of those movies about the same (for different reasons). The only one that's one notch below the others to me, though it's still enjoyable, is Close Encounters.

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Star Wars out of those options. I've always enjoyed it.

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I picked Bladerunner, because I remember sitting in the theater watching it, totally amazed and enthralled by that vision of the future. Honestly, watching Daryl Hannah cartwheel across the screen and land on Harrison Fords shoulders, clamping her thighs on his head had nothing to do with it.

Close Encounters always seemed like too much of a conspiracy movie, rather than sci fi. (or is it Sy Fy?) Still entertaining, but not so much sci fi.

Star Wars was ultimately sci fi, with the exception of the popular "Force", which was sort of used by the writer, to do whatever he needed to do. It gets major kudos for introducing what is probably the coolest scifi weapon ever, in the lightsaber. Who watched that movie and didnt want to go home and build one? The Wookie's crossbow (did it have another name?) was close second in a universe equipped with blasters.

Alien was so cool, because it took normal horror movie genre and moved it to space and the future. I always liked the concept of that future, minus the Aliens of course. Could they maybe have just made the original and the sequel?

I don't know what my mindset was when I saw 2001. I don't remember a huge impact. I probably should re-watch it.

TJ

This is a hard one toughest yet decision to make.

I’d have to go for the wooden simplistic use of dialogue, STAR WARS!

Its simple storyline and magical wizardry visual effects and Dolby stereo film mix get my vote.

I have all the nominees that are on this vote list all are great 10/10. But STAR WARS with its elegant sweeping John Williams score who scored for Close Encounters of the Third Kind of the same year (1977) which are two of the first films to use Baby Boom on 70mm six-track magnetic strip.

2001 is also an elegant looking film but not much original score happening in it. Its got a lot of what I like, dialogue panning moving from speaker to speaker over the LCR on the re-mixed down-mix laserdisc which would have originally played over five screen fronts, left left-centre centre right-centre right and single monaural surround.

Alien is one of my favourites its like don’t walk down their alone or its curtains! Alien has lots of dialogue panning happening on it.

Close Encounters of The Third Kind I recently brought a new second edition region 2 that looks a bit better in picture over the first edition region 2 DVD where it has some green colour issues where there is a soft bluish background and the hot white light beaming down onto the truck casts a green smearing that washes out some background image detail.

The sound on it is wow breathless!

Blade Runner now I like the theatrical version and international version that is extended. I just can not stand the abrupt ending on the directors editions where the Vangelis score cuts in! I like the soft dreamy ending after watching a rather depressing film not saying I don’t like it, its just a depressing dark film and the camera swooping over the hills at the end with the score then fades to black is spot on!

I’m glad Ridley produced an unaltered six-track Dolby stereo version which sounded fantastic from the opening. Deep frequency response reaching down to 25Hz rumbles the living room sofa via a large cinema size JBL 4645 18” sub bass.

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2001: A Space Odyssey

A masterpiece, simple as that. I first saw it at a theatre in 1968 when I was ten years old. It left an impression on me even at that age. When videotapes came out the first one I bought was this movie. When DVD's entered the market this movie again was one of the first ones I bought.
I try to watch it at least once a year.

I'd also like to say that Serenity is also very entertaining, though maybe not a classic like the poll movies. I still would rather watch Serenity than any of the others on the list except for 2001...

2001

Difficult choice. I think that seeing all of the others too many times made up my mind.

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None of the above? My choice would be the original 1951 "The Day the Earth Stood Still" Of course, that's strictly my opinion.

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Neptune- The original Dark Matter.

The author feels that this technique of deliberately lying will actually make it easier for you to learn the ideas. - Donald Knuth

Did you see it in Cinerama?

The first so you have the region 1 DVD. The word is that is the best version with all the crazy wild dialogue panning in it! (The later DVD version that was released was re-mixed! YUCK! I believe they also used the same version for the blu-ray YUCK)!

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Bart Sibrel is owned by the (Buzz-Lite-Punch) right on the chops.

We came in peace for all mankind…
The moon no longer as any astronomical importance! Thanks to NASA for defacing it!