Its so sad for Galatasaray to be in that group with Bayern. Its impossible to ge even 1 point from them in my opinion - there is huge power difference. But I suppose Galatasaray can challenge Kopenhag. Its unlucky for Kopenhag too - they drew nearly all strong teams from pots. They could have chance to go next round if they could be in a different group. So same scenario for them. Competition only for 1st rank at 3rd rank in that group. Otherwise teams are literally divided to two.
Bayern Munich and Manchester United is the strongest teams on group A so it's hard for Galatasaray to compete against these teams but everything still possible to happend because group stage hasn't to begin yet and if Galatasaray can able to beat Manchester United i think there is a good chances for them to qualified but indeed this is really hard because during their participant in champion league turkish teams always be recognized as mediocre team and the most realistic position for Galatasaray probably 3rd places however if i am not mistaken Galatasaray have been advances to round of 16 on 2013 and at that time they were fight against Schalke and Galatasaray were successfully to advances to quarterfinal but unfortunately their journey have to stopped on that stage because they lose from Real Madrid
Judging by the quality of players in each of the clubs in group A of the UEFA Champions League competition, Bayern Munich and Manchester United are the two strongest teams but that doesn't in any way guarantee that the two top teams are going to progress to the knockout stages of the competition at the expense of the other two teams especially Galatasaray.
Galatasaray has been very impressive with their performance this season which they continued from their last season incredible campaign that helped them win the Turkish Super Lig title. Mauro Icardi has been very instrumental to the club's success and has been very prolific in front of goal and with the striker at his best, Galatasaray might pull a surprise and progress to the knockout stages.