I started watching the show last season and stopped. I caught a show and Daniel had died or something and had "come back " to help. I was just wondering if anyone could tell me what exactly happened?
Thanks!
Well from what I remember, he could chose to evolve into a new level of existence being taught by Oma i think. From then on in Sg-1 gets a new member, Jonas Quinn and life goes on. He occasionaly pops in to help them out if at all possible. In the end of season 6 something happens to him when he confronts Anubis who appears to be more powerful than Daniel. Spoiler for season 7 sais that Sg-1 finds him on a desserted planet without ANY recolection of Sgc or previous years
hope that helps, and that it makes sense…its late here 
-Mith
SPOILERS AHEAD
Ok, he was on Jonas Quinns homeworld and they were experimenting with a Naquadria bomb (very big boom) and Dan was observing. Something goes wrong and the bomb starts counting down. Dan runs in and pulls the Naquadria out of the bomb, but in the process get a lethal dose of radiation. He heads back to the SGC where his body slowly breaks down and we see some sad moments of the team saying goodbye. While thing is happening Oma who is an all powerful asended being comes to Dan and tries to help him ascend so he won’t die. It ends up working and Daniel floats away and the team wonders if they’ll ever see him again. Jonas feels guilty about the whole thing (his government tried to blame Daniel for the accident to cover their own behinds) and so steals some Naquadria for the SGC. He seeks asylum with the SGC because he would be considered a criminal back home. He studies up on all of Daniel’s research (he has some kind of uber genius memory) and asks to take Daniels place. Jack refuses but later is told that a Russian will be joining the team. Faced with the options he picks Jonas.
Dan comes back in asended form a few times to give council and returns in Season 7.
Thanks guys! I really appreciate it!