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Updated: Jul 9, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
地球近傍小惑星の分布を理解する
1Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853-6801, USA. Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. Observatoire de la Cote d'Azur, Boite Postale 4229, 06034 Nice C.
Science (New York, N.Y.)
|June 24, 2000
まとめ
研究者は,約900キロメートルの大きさの近地小惑星 (NEAs) を予測しており,その40%が発見されています. 残された多くのNEAは,軌道が大きくて検出が困難です.
科学分野:
- 天文学と天体物理学について
- 惑星科学は惑星科学である.
- 軌道ダイナミクス 軌道ダイナミクス
背景:
- 近地小惑星 (NEAs) は,潜在的な衝突リスクを持ち,太陽系の進化を理解する鍵となる.
- NEAの現在のカタログは,特に小さいまたは動的に異なる集団については不完全です.
研究 の 目的:
- NEAの軌道と大きさの分布を決定する.
- キロメートルサイズのNEAの総人口を推定し,現在の調査の完全性を評価する.
主な方法:
- 源領域から観測された軌道までのNEAの数値統合.
- 様々な軌道にある小惑星の観測バイアスとサイズ分布の推定.
- 既知のNEAデータに適合するモデル集団の開発.
主要な成果:
- 絶対大きさは<18 (キロメートルの大きさ) の推定900のNEAが存在する.
- そのうち約29%はアモールの軌道,65%はアポロの軌道,6%はアトンの軌道に存在する.
- 約40%のキロメートルの大きさのNEAが発見されており,残りは検出が難しい軌道にあると推定されています.
結論:
- 現在のNEAの人口は,特に離心軌道や傾斜軌道にある物体の場合は,著しく過小評価されています.
- アクセスが困難な軌道領域に存在するNEAについては,検出戦略の改善が必要である.
- この研究は,潜在的に危険な小惑星のより正確な調査を提供します.
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