The original notebooks of Sir Douglas Mawson containing observations of the aurora australis by members of the British Antarctic Expedition at the time of the Tunguska explosion over Siberia on 1908 June 30 have been inspected, and it is found that, contrary to some suggestions which note that geomagnetic transients were witnessed elsewhere, and that the BAE was in winter quarters close to the south magnetic pole at the time, no exceptional auroral activity was seen which might have provided useful information on a planet-wide disturbance at the time of the event. However, an exceptional aurora was seen about seven hours prior to the explosion, and it is suggested that this may have been due to an anti-solar comet-like ion tail producing that auroral display whilst the impactor was still far from Earth.
Australian Journal of Astronomy
- Pub Date:
- March 1993