[VonLipwig]

If a Death Star takes a couple of decades of build wouldn't be obsolete by the time its finished?

Also, I am not that into Star Wars but I understand that the Death Star is big? Like a small planet right?

Wouldn't it just be cheaper to take a shovel to one of Saturn's moon. Mount a giant cannon and nail on some fairly large booster engines?

I mean.. the whole idea of building a planet sized space craft from metal seems silly when there are plenty of large space objects ready to be commandeered and turned into very large space vessels. Should also be noted that a moon has a long track record of surviving very large impacts. A metal structure? Perhaps not so much.

[jerf]

"If a Death Star takes a couple of decades of build wouldn't be obsolete by the time its finished?"

Most evidence would suggest that in the Star Wars universe, physics and technology have basically been fully explored for thousands or tens of thousands of years. What's left is style and what exactly is done with it. In the extended canon it is revealed that the Death Star isn't even particularly special and that various superweapons of similar capabilities have been developed off and on in the past several thousand years, determined more by the political environment of the time than the tech environment.

As for the rest, wild handwaving. We don't know how the physics of their space travel works, so it's possible that a moon can not simply be turned into a hyperspace-capable ship any easier than it is to simply build one.

Incidentally, while we're on the topic, here's some relatively-well founded handwaving: http://www.theforce.net/swtc/hyperspace.html

[DennisP]

I figure technological advancement is probably an S-curve, and by the time you have a galactic empire, things have leveled off quite a bit. There's probably not much change over a couple decades. (And in Star Wars, things actually seem to be decaying a bit.)

Also you seem to be assuming that the Death Star is big just for the sake of being big. More likely, most of the mass is the actual planet-destroying weapon, as well as the engines for moving it around.

[Shivetya]

One of the best series exploring this area is the http://en.wikipedia.org/wiki/Lensman series. Weaponry was only useful; not obsolete; up until the enemy found out about it. In the environment he created you could pretty much negate or create something once you knew it was possible. As such they went to great extents to keep things secret.

In the end, the final solution was crashing light speed plus planets from alternate dimensions into your target planet, bonus points for negative matter planets

Anyone interested in science fiction should read these books but realize that they are a product of their time and it may offend the sensibilities of some readers.

[freehunter]

>If a Death Star takes a couple of decades of build wouldn't be obsolete by the time its finished?

Only if there's something better in the meantime. Which there really wasn't in Star Wars. Also it can be built while it's in operation, like a supermarket remaining open during remodeling.

>a planet sized space craft from metal seems silly when there are plenty of large space objects ready to be commandeered and turned into very large space vessels.

Would a planet be able to retain its structural integrity while being carved out to house a million soldiers? Having to build structures on the surface would defeat the purpose of a Death Star.

Also the Death Star has defenses, so it doesn't traditionally need to withstand large impacts.

[ajuc]

Even now, on Earth, we are using airplanes that were built decades ago. We are also building new aeroplanes designed decades ago (F-16), that have only electronic upgrades (avionics, radar, etc).

Most armed forces around the world consist of vehicles designed in '80 or '90. And I think Death Star is more complicated than tank or plane.

[timwiseman]

When I served in the 82nd some of the NCOs told me that some of the vehicles we used had seen service in Vietnam. I never verified this, but I did verify that some of them were manufactured in the Vietnam era.

[razzmataz]

Did you serve while the Sheridan tanks were still being used? Those saw action in 'Nam.

[batista]

If a Death Star takes a couple of decades of build wouldn't be obsolete by the time its finished?

No.

For one, it's not like the Galactic technology state of the art is accelerating in any major way. Looks like they have reached a plateau a lot of time ago.

Second, even assuming an accelerating technical rate, while parts could be obsolete (like the computing system and such), the major things that take time to build, namely, the construction part (skeleton, infrastructure, walls, etc) don't change that much, if at all. If it was delivered just today, would an '80s skyscraper, say, be "obsolete"?