A nuclear reactor disaster at Chernobyl No. 4 in the former USSR (now the Ukraine) on April 26, 1986 at 1.23am local time resulted in an official Soviet death toll of 31 people. No systematic records were kept of subsequent deaths, but over 1.7 million people were exposed to radiation. It is not known how many of the estimated 200,000 people involved in the clean-up operation died in the 5-year period following the disaster, as no systematic records were kept.  

The highest altitude art exhibition (aircraft) was 10,150 metres (33,300 feet) above sea level and was achieved by Antonov Company (Ukraine) and Producer Centre Boyko, Gallery Globus (Ukraine) in the AN-225 MRIYA aircraft at Gostomel Airport, Hostomel, Ukraine, on 27 September 2012. The exhibition took place during the international airshow ‘Aerosvit’ and was open from 27 September to 1 October 2012.