ガス 巨星 の 成長 は,小石 の 漸進 的 な 蓄積 に よる
Harold F Levison1, Katherine A Kretke1, Martin J Duncan2
1Southwest Research Institute and NASA Solar System Exploration Research Virtual Institute, 1050 Walnut Street, Suite 300, Boulder, Colorado 80302, USA.
Nature
|August 21, 2015
まとめ
ガス巨大惑星の形成は小石の蓄積によって説明され,小石の形成がゆっくりと進むと,大きな小惑星が小さな小惑星を散らばって成長します. これは太陽系における 観測されたガス巨人の数に繋がります
科学分野:
- 惑星科学
- 天体物理学
- 計算による天体物理学
背景:
- 木星や土星のようなガスの巨大惑星は 固い核から形成されると考えられています 地球の質量の約10倍です
- 太陽の星雲が散らばる前にこれらのコアを形成することは,惑星形成モデルにとって重要な課題です.
研究 の 目的:
- 太陽の星雲の寿命内に 巨大ガス核の形成という課題に取り組むために
- 観測された太陽系の構造と,特にガスの巨星の数を調和させる.
主な方法:
- 惑星間の重力相互作用を含む小石の増殖のシミュレーション.
- 惑星小惑星の成長と散乱のダイナミクスに対する小石の形成率の影響をモデル化.
主要な成果:
- 小石がゆっくりと形成されると 惑星粒子は重力的に相互作用します
- 最大の惑星粒子は小さな惑星粒子を散らばって 過剰な成長を防ぎ 巨大な核の数を制限します
- モデルでは,太陽系観測結果と一致する5〜15AUの間の1〜4のガス巨星を成功裏に形成している.
結論:
- ゆっくりとした小石の形成は,ガス巨人の形成のための小石の蓄積モデルにおける重要な要因です.
- 惑星間の重力相互作用は 核の成長を制御し 太陽系の構造との不一致を解決する.
- この洗練された小石の蓄積モデルは 観測されたガスの巨星を形成するための 実行可能な経路を提供します
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