can someone please tell me why Prometheus was on LV223 not LV426

The only likely scenario is that the Engineers (Giants) went off in different directions to try and escape their bio-weapon gone wrong. One of them landed on LV-426. Another on LV-519 or whatever and so on.. (making numbers up here obviously to demonstrate the point) So the company for decades after Prometheus searches the general systems nearby, and wants to secure the "weapon", and has been scouting for it, and gets the signal. So they set up the crew of the Nostromo in Alien to bring it to them. Does this sound reasonable? Either that, or to throw everyone off, they changed the designation of the planet in their data banks to LV-426 so that no one would find out.

Bingo! I have to belief that Prometheus is a prequel to the PREQUEL. Also, in Alien, there's a Space Jockey "behind the wheel" with his chest blown out; no such SJ at the end of Pro. Lastly, though Ash is the first one to attempt to decode the beacon the Nostromo picks up on, Ripley gives it a try and it takes the computer (seemingly) hours to even decipher a little bit of it. Therefore it cannot be Shaw's warning, which was stated in simple English.

[i]Lastly, though Ash is the first one to attempt to decode the beacon the Nostromo picks up on, Ripley gives it a try and it takes the computer (seemingly) hours to even decipher a little bit of it. Therefore it cannot be Shaw's warning, which was stated in simple English.[/i] Shaws message may have been in English, but WHERE do you think she transmitted it from? The tiny fragments of the Prometheus or the lifeboat with the Xenomorph in it... Obviously she transmitted it using the communication technology of the Engineers, and that would allow for someone to recognise the same technology being used to send a different message from another planet. They wouldn't necessarily know what it says but they could recognise that it is Engineer technology... and if they get another David android busy learning the languages.... they will know what it means soon enough.

[i]Either that, or to throw everyone off, they changed the designation of the planet in their data banks to LV-426 so that no one would find out.[/i] You can eliminate that theory... from what we know of LV-223 and LV-426 they cannot be the same planet. Simply changing the designation would not shrink LV-233, make it very volcanically active, remove the oxygen from its atmosphere, move it 4.5 light years further from Earth.

[i]can someone please tell me why Prometheus landed on LV 223 not LV426, does this mean, that there will be another movie made after this one to explain how ALIEN came in contact with humans[/i] the simplest answer, taking your question as it's asked, is that LV 426 didn;t match the critera they used to navigate. They had six stars in a pattern, they looked for it, and then of the five stars, one seemed like our sun, and it had a ringed gas giant with moons, one of which seemed to have an atmosphere that might support life (it was pretty close, match for Earth's atmosphere until they realised it had 3% Carbon Monoxide - (weird, but fatal...) LV-426 is orbiting a planet around one of the other five stars. LV -426 was in the binary star system Zeta 2 Reticuli, which is 39 light years from Earth. LV-223 is 34.5 light years, so they are definitely in different solar systems. But they ARE in the same neighborhood.

*facepalm*

It was a different ship. The ship in Lv 426 is millions of years old, has no stasis pods. Also imagine the crew of the Nostromo bumping into Weylands dead body? Now that doesnt make sense. Also the eggs in the lower chamber had a motion sensor detector which was explain. plus the transmission was a warning in binary code.

[i]LV-426 is orbiting a planet around one of the other five stars. LV -426 was in the binary star system Zeta 2 Reticuli, which is 39 light years from Earth. LV-223 is 34.5 light years, so they are definitely in different solar systems. But they ARE in the same neighborhood.[/i] Not necessarily. We are not told which system LV-223 is in; it could be 34.5 light-years from Earth in the OPPOSITE direction. LV-223 (unknown system) and LV-426 (Zeta II Reticuli) could therefore be as far as 73 or 74 light-years from each other.

Different planets, them alien star charts looked pretty comprehensive so I'm sure they have more than one planet stacked with WMAs. As Ridley Scott directed Alien and Prometheus, I'm sure he didn't pick the numbers out of a hat. There was too much trash left in the alien ship after the big guy killed gramps, his security and the Scottish chick that they didn't run into in Alien. I'm also thinking the alien at the end of this movie did not evolve into the alien we saw back in 1979. The aliens on lv426 had no human contact, but they were in contact with the big guys who have our DNA so would evolved into something similar. Or perhaps that is why the alien at the end of Prometheus looked so different. But hey, apart from human technology devolving as they usually do when prequels come 30+ years after #1 and the lack of depth in the story and plot, this has been the best 3D I have seen so far. If you don't think about it too much it's a fun watch. David was a wicked character in the coolest sense, the scientist were as naive and irritating as scientist usually are when it comes to movie scientists, would love to see more on the sentient alien race so I hope there is a sequel. Don't over analyze this movie. We all have our ideas on how we would have made it, but to make something like this you need the skills, a MASSIVE budget and resources well beyond reach to many of us. Maybe the director's cut will look different ;)

Im surprised no one has come to the concussion that the ship shawtook off at the end of prometheus could have been the ship in lv-426.their could of been engineers in hyper sleep in that ship to,I can see david awaking them now that we know their is a sequel to prometheus it could be possible.

The planets are not the same... But they are close by... now this does not mean around the same planet as this would offer a problem as far as continuity, how did Weyland miss LV 223 while they colonized baron LV 426 when LV 223 is partially Tera-Formed already? I would not say its also around another planet in the same system... So this is not the case of say like LV 426 is Tythris and LV 223 is Rhea around Saturn. Or say how LV 223 is Rhea around Satrun and LV 426 is Europa around Jupiter. I would assume that LV 223 is in one System around one Sun and LV 426 is in a System of a near by Star thus Light Years away but not vast amounts.

As far as the events of LV 426.... well there are enough hints to suggest the Derelict has been on LV 426 for a long long time, much more prior to Prometheus. And on top of that Ridley had confirmed what happened, here is a run down by combining what Ridley said about the event... The Derelict had left the System that LV 223 was in between 1800-2200 years ago. It was carrying a Cargo of Xeno Eggs to a unspecified destination, however it did not get that far before the ship encountered a problem. One of its Cargo had been compromised somehow and a Face Huger some how got to the Pilot. This Pilot then realizing he had been infected set a course for the closest baron place to Quarantine the Bio Weapon Cargo and Activated/Recorded a Warning Beacon. The chosen moon was LV 426 and has he was attempting to land on LV 426 he started the process of being Chest Busted but he managed to crash land on that moon. As far as we know the first Human interaction with the Xeno was on Lv 426 and by Kane when he got Face Hugged. Again what becomes of LV 223 from the events of Prometheus to Aliens and the Colony on LV 426 is unknown and could be a potential Plot Hole, especially if LV 223 and LV 426 are within close proximity and by that i mean say within a few Light Years let alone same Star System... I would assume they are in the same constellation, but the Star Map does not match Zeta Reticuli or any close by Systems, and Zeta Reticuli is not 34 light years but 39... But i guess Ridley means near Zeta Reticuli and well in the scale of Space Travel for a Craft that has FTL well that could be even as far as within 10 Light Years. The only system i found that matches the Star Map is Libra Constellation... However we have to remember that just because we see a group of stars in the sky that appear close they may be further than we think, we could see 5 stars close by in the sky but actually one of those stars may be closer to another in the sky that appears not even close to it, while as we see in the sky the star closest to it may be much further.

[quote]...one of which seemed to have an atmosphere that might support life (it was pretty close, match for Earth's atmosphere until they realised it had 3% Carbon Monoxide - (weird, but fatal...)[/quote] Actually, it was carbon dioxide, not monoxide that the planet had at 3%. In addition, 3% CO2 wouldn't necessarily be fatal. Fatal concentrations are more along the lines of 6-8%.