まとめ
1966年のSNAP-9A発電機の崩壊により,大気中にプルトニウム-238が放出されました. 分析によると,このプルトニウム238は,おそらく再入地中に燃え上がり,10ミリミクロン粒子に切り裂かれていた.
科学分野:
- 大気化学 大気化学
- 核工学は,原子力工学である.
- 環境科学 環境科学
背景:
- 1966年の事件は,衛星核補助発電機 (SNAP-9A) の解体でした.
- このイベントにより,地球上の平流圏にプルトニウム238が放出されました.
- 放出されるこの物質の運命を理解することは,環境と安全の評価に不可欠です.
研究 の 目的:
- SNAP-9A発電機から放出されたプルトニウム-238の大気の運命を決定するために.
- 再帰で除去されたプルトニウム238.8の粒子の大きさの分布を分析するために.
- 完全な燃焼と消去の仮説を確認するために.
主な方法:
- ストラトスフィアのプルトニウム-238の在庫の分析.
- 粒子サイズ分布の見積もりは,再入力の物理に基づいています.
- 推定粒子の大きさと理論的な燃焼モデルを比較する.
主要な成果:
- ストラトスフィアのプルトニウム-238の在庫は,SNAP-9A発電機からの総量と一致しています.
- 証拠は,再入力の際に,ピロフォリックプルトニウム-238の完全な燃焼と消去を示唆しています.
- 推定算術平均粒子の大きさは約10ミリミクロンでした.
結論:
- SNAP-9Aジェネレーターのプルトニウム238は,大気圏への再突入中に完全に燃え尽き,破壊された.
- その結果生成されるプルトニウム238の粒子は,平均サイズは10ミリミクロンで,非常に小さい.
- この発見は,宇宙で発生する発電機が故障した後の放射性物質の拡散の理解を支えている.
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