Questions, Questions

[Davey]

1) What happened to the Asgard population in the ship when Our Guys took it over?
2) What happened to Todd and his wraith after the Daedelus was taken back, and what happens to the experiment Todd had agreed to? Did Todd find out the truth about the evil Asgard?
3) Why did the Asgard stay in the uniforms if they didn't need them?
4) What happened to Colonel Caldwell?
5) Can someone explain how they replaced the stargate in Atlantis, and why Radek and Shepard weren't killed EVEN IF the explosion was reduced? I didn't understand Rodney's explanation.
6) What happened elsewhere in the galaxy if other gates were destroyed? How did they get replaced?

Having said all that I think the two-parter was just great. I loved the dynamic between Jackson and McKay.

[hedwig]

You get to pretty much guess the answer to all your questions, because they were never explained on the show.

[Davey]

I was sort of hoping that there were in fact more clues to those questions (!!)

[Xaeden]

Okay so...

I don't understand your first question. Humans never took over a ship that the Asgard were on. The Traveler ship engaged with two Asgard ships above the ice planet. The Traveler ship destroyed one, and the other escaped into hyperspace. The writers intended to return to the Asgard in season 6, so there's nothing definitive to tell you about what happened to them after, as Hedwig notes.

The answer to your second question will be addressed in the 17th episode.

Do you remember how in "First Contact" (the first episode of the two-parter), they tried to crack open one of the suits and it exploded, prompting Sheppard to note how they must really want to keep their identities a secret? That answers your third question: The Asgard don't want anyone to know that they're still alive and active in the galaxy, especially the Wraith. One of them gives up the act when Daniel questions him and says that he knows he's not human, Ancient, or Wraith. Presumably, that Asgard thought that Daniel would never make it off the planet alive and thus he would never be able to tell anyone what he saw.

Caldwell is fine, you'll see him again in the finale. He was likely only in "First Contact" due to scheduling issues. He was also busy with other work back in season 4, which is why he appeared less that season and why they brought in Colonel Ellis to pick up the slack.

Replacing the Stargate: The Daedalus picked a Stargate up from some uninhabited world and brought it back to Atlantis. Not complicated.

The explosion: The shield contained the explosion long enough so that, by the time the shield failed, it was big enough to damage the room, but not big enough to kill everyone in the vicinity. Of course, that the shield was able to hang on long enough for it to be a cool, but non-life threatening effect was awfully convenient.

As to your last question, any Stargates that blew up did not get replaced elsewhere in the galaxy. Their explosions would have been devastating, wiping out most to all life on each planet that this happened on. There's therefore no reason to replace the gate on a world devastated by a Stargate explosion. Again, Atlantis was spared that only because the shield contained the explosion until it was barely big enough to damage a single room in the city.

[Davey]

I appreciate the focus in your reply. About replacing the stargate, I think McKay told Jackson that the Daedalus picked one up from the chain of space gates, but it wasn't clear. How did Daedalus do that and install it into Atlantis if the gate room was destroyed? And if Jackson didn't know about it, how did he find out that he had to return to Earth?
About the Asgard, what happened to the Asgard who worked on the Daedalus, and how exactly did the Asgard break up into factions?
How many planets or populations were destroyed while the Atero device was operating?

[Xaeden]

You're right, it was one of the spacegates from the void. The gateroom wasn't destroyed, though, just damaged. The explosion was only big enough to blow out the windows and drop some rubble near the computer area. All of that was easily repairable. You're also right that it is unclear how Jackson received orders from Landry to return home. It wasn't addressed in dialogue, but it's possible that Earth tried to reach Atlantis for some reason and when they couldn't make a connection, they dialed the Pegasus Alpha Site instead and relayed information that way. Remember, Earth has the ZPM power to dial Pegasus at this point.

It's also possible that the Daedalus used the control crystal and a ZPM to dial Earth from another planet in the Pegasus galaxy before picking up the spacegate. Travel time to beyond the edge of the galaxy and back would have taken a few days and they probably spent some time repairing the Deadalus before setting off to get the gate, so it may have been important to them to brief Earth on what had been happening as soon as they could (Atlantis regularly dials Earth to transmit mission data and if Earth doesn't hear from them at the expected time, they'll think something is wrong).

Hermiod made his final appearance in season 3, episode 8 and was last mentioned in season 3, episode 14. His parting was never shown on screen, but it is assumed that he returned to Ida to die with the rest of the Asgard in the Sg-1 finale.

The Vanir (or Pegasus Asgard) took it upon themselves to lead an expedition to the Pegasus galaxy around 10,000 years ago. Whether they formally broke from the Asgard or they simply went off under the noses of the Asgard Ruling Council and intended to rejoin their brethren when they were done (and bring back the knowledge they gained from human experiments) is unknown. We do, however, know they had no intention of staying in Pegasus and only remained there because the Wraith successfully destroyed their intergalactic ships after overwhelming the Ancients.

As to the extent of the Attero device's damage, I'm not aware of any mention to planets destroyed or lives lost beside of the Traveler colony. I could be forgetting a reference, but there's definitely not an overall count as Atlantis has no way to track that.