Career
He curls out of the Hvidovre Curling Club. Stjerne has participated in five World Junior Championships. He played as third for Kenneth Jørgensen in 2004 and 2005, finishing outside of the playoffs in both years.
He then skipped his own team at the World Juniors in 2006, 2007, and 2008, finishing fifth, fourth, and seventh, respectively.
Then, in the 2009 World Junior Curling Championships, Stjerne and his team made the playoffs as the second-ranked team Stjerne skipped a team at the 2010 European Curling Championships, and led his team to the playoffs.
Stjerne defeated Germany"s Andy Kapp in the page 3 versus 4 game and then edged Switzerland"s Christof Schwaller to play Norway in the gold medal game.
He was defeated by his father, Tommy Stjerne, in a tournament that decided the Danish representatives at the 2011 Ford World Men"s Curling Championship, and went with his father"s team as their coach.
Stjerne returned the next year at the 2011 European Curling Championships and again made the playoffs, but lost in an extra end in the page 3 versus 4 game to the Czechoslovakian Republic"s Jiri Snítil, relegating him to the bronze medal game. However, Stjerne defeated Snítil in nine ends on his second try, earning the bronze medal.
Stjerne represented Denmark at the 2012 World Men"s Curling Championship in Basel, where Denmark finished outside of the playoffs.
Later that year, he led Denmark to a 4th place finish at the 2012 European Curling Championships. He followed this up by placing 4th at the 2013 Ford World Men"s Curling Championship, and again finishing 4th at the 2013 European Curling Championships.
Stjerne skipped Denmark at the 2014 Winter Olympics, leading the team to a 6th place finish with a 4-5 record.