Noted astrobiologist Imre Friedmann died yesterday morning.
Friedmann's main interest was the microbial ecology of absolute extreme environments - how life adapts to some of the harshest locations on Earth - and what this says for the possibility that life can exist in similar locations on other worlds. This research required many field trips to some of the harshest locations on our planet.
Also, of note, Friedmann guided the developing careers of many of today's leading astrobiologists.
These photos, taken by astrobiologist Dale Andersen in 1996, show Friedmann in his element - at Battleship Promontory in Alatna Valley, Antarctica.
Here is a trip report by Kevin Hand - also to Battleship Promontory - written a decade later.