DETONATING FIREBALLS.

Press, Volume LXV, Issue 19772, 9 November 1929, Page 23

DETONATING FIREBALLS.

TO THE EDITOR OF THE PRESS Sir, —Preliminary investigations of observations received have shown that the detonating fireball which occurred on the evening of October 7th last was a vary interesting body. It first became luminous about 70 miles up somewhere above Lake Ellesmere. Sweeping down in a steeply-inclined path it took only a few seconds to reach the point where it finally disappeared, about 30 miles north-east of Christchurch in Pega.«us Bay, where it had a height of 11 miles, it left behind it a trail of smoke-like matter which persisted for a considerable time. The loud reports heard in many places were not the result of any actual explosion of the fireball, but were due to what is termed » ballistic wave, created by the rapid passage of the body through the atmosphere, and heard only near the lower end of the fireball's journey. The response of your readers to my previous request for observations was very gratifying, a total of 45 replies being received, and excellent data will result from a final examination of all the observations sent in. I desire to thank all those readers who, by their co-opera-tion, have so materially assisted in the examination of the fireball. Their response easily constitutes a record for fireball observations in New Zealand. — Yours, etc., K. A. MeIXTOSH, F.R.A.S. 1 Milford street, Ponsonby, November sth, 1929. [A special article bearing on this subject will be found on page 13. —E<L» The Press.]