Here is my own little (incomplete) Top-10 list of favourite pasttime achievements:

  1. Experiencing the birth and development of my amazingly cute and clever boy Oliver.
  2. Being expedition scientist on the Tycho Brahe Expedition 1998 to Greenland where we searched for the famous Greenland meteorite. Read one of the diaries or Wayt Gibbs nice article in Scientific American. See also a few pictures here.
  3. Running the Copenhagen Marathon.
  4. Experiencing the total solar eclipse on 2 July 2019 at La Silla. See the pics and webcast and article here and here.
  5. Serving a visiting astronomer on Soneva Fushi and Soneva Jani in the Baa Atoll the Maldives. Unbelievable places, close to sky, sea and nature.
  6. Jumping out of an aeroplane (and surviving)
  7. Participating in the Kap York Meteorite Expedition 1994. The research for this expedition inspired (in part) Peter Høeg when he wrote his famous novel Miss Smilla's Feeling for Snow
  8. Doing the Overland Track in Tasmania in 3.5 days (in the winter)
  9. Climbing the highest mountain in Germany, Mt. Zugspitze four times
  10. Winning the prize for the school's best exam in 1989
  11. Doing the 102 mile (164 km) El Tour de Tucson road bike race.
  12. Freediving to 9.7 metres in first session.
  13. Static breathhold time (pool, first session): 2:32

...room for more fun :-)