is aegean airlines part of the star alliance
Yes
Star Alliance
 Aegean Airlines, Greece's largest airline by number of passengers, joined on 30 June.
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Star Alliance [SEP] 2008–2010: Second decade of operations
At the time, it was rumoured that the switch was Continental's first move in a planned merger with United Airlines. Two months later, Brussels Airlines joined the alliance. Brazilian carrier TAM Airlines joined Star Alliance on 13 May 2010, increasing its foothold in South America. Aegean Airlines, Greece's largest airline by number of passengers, joined on 30 June.