9P/テンペル1の塵粒は,ディープインパクトとの衝突前と後のものです
David E Harker1, Charles E Woodward, Diane H Wooden
1Center for Astrophysics and Space Sciences, University of California, San Diego, 9500 Gilman Drive, Department 0424, La Jolla, CA 92093-0424, USA. dharker@ucsd.edu
Science (New York, N.Y.)
|September 17, 2005
まとめ
Gemini-Nは,彗星9P/Tempel 1における大きな変化を観測した.
科学分野:
- 彗星科学は彗星科学である.
- アストロジオロジー アストロジオロジー
- 塵の物理 塵の物理
背景:
- 彗星9P/テンペル1は,ディープインパクトミッションの前と後に研究されました.
- 彗星の塵の性質を理解することは,惑星科学にとって極めて重要です.
研究 の 目的:
- 彗星9P/テンプル1から放出された塵のスペクトル特性と粒子の特性を分析する.
- 彗星の内部昏睡にディープインパクトミッションの影響を決定するために.
主な方法:
- 赤外線スペクトロスコーピー (7.8〜13マイクロメートル) を用いて,彗星の内部の昏睡状態を観察した.
- スペクトルエネルギー分布と派生した粒子の性質の分析.
- 噴出された塵の質量のモデリング.
主要な成果:
- アモルフなピロキセン,アモルフなオリビン,そして結晶のオリビンの兆候である顕著なシリケート放射特性は,衝突後1時間以内に発達した.
- 放出された塵の質量は10^4から10^6キログラムと推定された.
- シリケート特徴は26時間以内に減少し,スペクトルが衝突前の状態に戻った.
結論:
- ディープインパクトミッションは,彗星の塵の組成と性質に一時的な変化をもたらした.
- 衝突は,彗星9P/テンペル1の核に新しい,持続的な活性領域を作り出すようには見えなかった.
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