彗星C/1999 S4 (LINEAR) の破壊時の放気行動と構成
D Bockelée-Morvan1, N Biver, R Moreno
1Observatoire de Paris-Meudon, F-92195, Meudon, France.
Science (New York, N.Y.)
|May 19, 2001
まとめ
彗星C/1999 S4 (LINEAR) は断片化され,小さな原子核が氷の破片を失っていることが明らかになりました. 解体中のガスの豊富さは,メタノールと一酸化炭素のレベルが低いことを除いて,ほとんど典型的でした.
科学分野:
- 彗星科学は彗星科学である.
- ラジオ天文学 ラジオ天文学
- 惑星科学は惑星科学である.
背景:
- 彗星C/1999 S4 (LINEAR) は,その終末期に観測されました.
- 彗星の核は複雑な氷の体であり,断片化を経験する可能性があります.
研究 の 目的:
- 彗星C/1999 S4 (LINEAR) の破壊中のガス活動を監視するために.
- 断片化イベントからの破片の組成と質量分布を決定する.
主な方法:
- ガス活動を監視するために,ラジオ波長観測を用いた.
- 水 (H2O) に関するガス濃度の分析.
主要な成果:
- 彗星の核は2000年7月18日ごろから分裂し始め,その分裂は7月23日まで続いた.
- 小さな氷の破片の質量は,光学的に観察されたより大きな断片と比べられるものでした.
- 分裂後の質量は,半径100〜300メートルの核が数週間前から破片を放っていたことを示唆しています.
- H2Oに対するHNC,H2CO,H2S,およびCSの豊富さは,他の彗星と一致していました.
- メタノール (CH3OH) と一酸化炭素 (CO) の有意な欠乏が観察されました.
結論:
- 彗星C/1999 S4 (LINEAR) は小さな核で,断片化が激しい.
- 観測されたガスの豊富さは,彗星の組成に関する洞察を提供し,特定の枯渇はユニークな進化の経路を示しています.
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