 It has a maximum elevation of at Mawson Peak, the historically active volcanic summit of Big Ben.A July 2000 satellite image from the University of Hawaii's Institute of Geophysics and Planetology (HIGP) Thermal Alert Team showed an active and 50- to 90-metre-wide (164–295 ft) lava flow trending south-west from the summit of Big Ben.The much smaller and rocky McDonald Islands are located to the west of Heard Island.