NEAR-shoemaker宇宙船がエロスと打ち合わせした際のラジオ科学の結果
1Navigation and Mission Design Section, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. Department of Terrestrial and Planetary Geodesy, Centre National d'Etudes Spatiales, Toulouse, France. Applied.
まとめ
研究者は宇宙船のデータを用いて,小惑星433エロス (Eros) の質量と回転を正確に測定した. この小惑星"433エロス"は,安定した回転と均一な密度を持ち,レゴリットで覆われた表面を示唆しています.
科学分野:
- 惑星科学は惑星科学である.
- 小惑星のダイナミクス
- 宇宙船のミッション分析
背景:
- 小惑星433エロス (Eros) は,地球に近い小惑星で,小さな天体の形成と進化を理解するための重要な科学的関心のある目標です.
- 以前の研究では,Erosの物理的性質の正確な測定が欠け,詳細な動的および組成分析が困難でした.
研究 の 目的:
- 小惑星433 Eros.の正確な質量,重力ハーモニック,および回転状態を決定する.
- エロスの質量密度と内部構造を推測する.
- エロスの表面動態と物質輸送の可能性を分析する.
主な方法:
- 地上のドップラーと近地小惑星レンデブーズ (NEAR) -シューメイカー宇宙船からの距離追跡データを利用しました.
- 小惑星433 エロスの表面のランドマークの画像を分析し,その形状と回転を制限しました.
主要な成果:
- エロスの質量は (6.687 ± 0.003) x 10^18グラムで,散発密度は2.67 ± 0.03 g/cm^3.3 であることが判定されました.
- エロスの安定した回転状態を確立し,回転極の測定可能な自由プレセーションはありません.
- 計算された表面脱出速度は3.1m/sから17.2m/sまでで,レゴリットで覆われた表面を示している.
結論:
- 小惑星433エロス (Eros) は均一な密度分布を示しています.
- ダイナミックな環境は,重要なレゴリット覆面と重力潜在井戸に向かって物質輸送の可能性を示唆しています.
- 安定した回転と決定された物理的パラメータは,将来の小惑星探査とモデリングのための重要なデータを提供します.
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