seconds, Eventually it reaches a radius of almost 1lan., and by that time it has enitted, as therma.I radiation, mo"e energy than a 1'OOO MW powet plant produces in trc ,weeks. scoTched an area in excess of 250 1an2 and blinded (permanently or ternporariiy) people out to perhaps 5O lfl. from the explosion (rnuch farther at ' nignt). The mushroom cloud that is subsequently formed reaches a height of about ?O ItrI. and approxiraately the sare diameter" 173, A recent study 1l+/ by the Office of Technical Assessnent (0TA) of the United States Cong?ess desciibed the effects of a 1-Mt. explosion over the centre of a city with about ).} million inhabitants (netroit or Leningrad) ' Sone of the conclusions were: (a) That an air burst (neieht 1,800 m.) at night wou-l-d inmedis.tely kil-] about half a mi1lion people and injure an add.itional- 600,000 in Detroitl (l) That the cor esponding figures for Leningrad are about double those for Detroit" the reason being the (estimated) denographic differences between the two cities; (") That the area in which houses would be conpletely demolished, blovn out or or otherwise rendered uninhabitable vould exceed 300 haz; (a) That the incidence of burn injuries (many of them eventually fataf) among survivors of the blast could vary fron some thousands up to several- hund?eds of thousands, d.epend.ing on the number of people exposed to the line of sight fron the firebafl and on atmospheric visibility. 1?l+. With this large yield, the initial nuclear radiation vill cause very fev' additional fatalities or injuries. on the other hand, radioactive faflout with a &-/ "fn. Effects of Nuclear War", office of Technology Assessment of the Coneress of the United. States, 'l{ashington ' D.C-, 1979"Al35/392 [nE_Lasn Annex radiation intensity sufficient to be acutely harnful- voultl contaminate an area
**Analysis**
The text appears to be a scientific report discussing the effects of a nuclear explosion, including the destruction caused by the blast, thermal radiation, and radioactive fallout. The focus is on the immediate and long-term consequences on human populations, infrastructure, and the environment. The report provides specific statistics and estimates of the impact, suggesting that the topic is related to the consequences of a catastrophic event.

**Category**
Health, Science and technology