Mimas is the seventh of Saturn's known satellites:
orbit: 185,520 km from Saturn
diameter: 392 km
mass: 3.80e19 kg
Mimas was one of the Titans slain by Hercules.
Discovered in 1789 by Herschel.
Mimas' low density (1.17) indicates that it is composed mostly of water ice with only a small amount of rock.
The surface of Mimas is dominated by an impact crater 130 km across, known as Herschel; it's almost 1/3 of the diameter of the entire moon. Herschel's walls are approximately 5 km high, parts of its floor measure 10 km deep, and its central peak rises 6 km above the crater floor. The impact that made this crater must have nearly disrupted Mimas. Fractures can be seen on the opposite side of Mimas that may be due to the same impact.
The surface is saturated with impact craters. But no others are nearly as large as Herschel. This suggests that early in its history, Mimas was probably impacted by even larger bodies than the one that created Herschel which completely disrupted the new moon (wiping out the evidence of earlier large impacts) but that the impact debris then coalesced again to form present-day Mimas.
Mimas 是土星已知衛(wèi)星中距土星第七近的一顆：
公轉(zhuǎn)軌道：距土星 185,520 千米
衛(wèi)星直徑：392 千米
質(zhì)量：3.80e19 千克
Mimas是被赫拉克勒斯殘殺的巨人之一。
它于1789年由赫歇耳發(fā)現(xiàn)。
土衛(wèi)一的低密度(1.17)表明它主要由一部分巖石混合著冰水組成的。
土衛(wèi)一的表面主要是一個(gè)直徑130千米的環(huán)形山，取名為赫歇耳(Herschel)，它幾乎是整個(gè)衛(wèi)星直徑的三分之一。赫歇耳的內(nèi)壁大約有5千米高，部分底部深10千米，中央山峰在環(huán)形山中隆起6千米。造成形成這個(gè)環(huán)形山的撞擊一定差點(diǎn)將土衛(wèi)一撞碎。撞擊的反面可看到裂縫，可能就是因?yàn)檫@次撞擊。
表面的環(huán)形山處于飽和狀，但沒(méi)有一個(gè)同赫歇耳一樣大。這表明在土衛(wèi)一的早期歷史中，可能被一個(gè)比創(chuàng)造出這個(gè)環(huán)形山的星體更大的物體撞擊，使新衛(wèi)星完全破裂（抹去當(dāng)時(shí)所有表面撞擊痕跡），但后來(lái)碎片又合并在一起組成了今天的土衛(wèi)一。
orbit: 185,520 km from Saturn
diameter: 392 km
mass: 3.80e19 kg
Mimas was one of the Titans slain by Hercules.
Discovered in 1789 by Herschel.
Mimas' low density (1.17) indicates that it is composed mostly of water ice with only a small amount of rock.
The surface of Mimas is dominated by an impact crater 130 km across, known as Herschel; it's almost 1/3 of the diameter of the entire moon. Herschel's walls are approximately 5 km high, parts of its floor measure 10 km deep, and its central peak rises 6 km above the crater floor. The impact that made this crater must have nearly disrupted Mimas. Fractures can be seen on the opposite side of Mimas that may be due to the same impact.
The surface is saturated with impact craters. But no others are nearly as large as Herschel. This suggests that early in its history, Mimas was probably impacted by even larger bodies than the one that created Herschel which completely disrupted the new moon (wiping out the evidence of earlier large impacts) but that the impact debris then coalesced again to form present-day Mimas.
Mimas 是土星已知衛(wèi)星中距土星第七近的一顆：
公轉(zhuǎn)軌道：距土星 185,520 千米
衛(wèi)星直徑：392 千米
質(zhì)量：3.80e19 千克
Mimas是被赫拉克勒斯殘殺的巨人之一。
它于1789年由赫歇耳發(fā)現(xiàn)。
土衛(wèi)一的低密度(1.17)表明它主要由一部分巖石混合著冰水組成的。
土衛(wèi)一的表面主要是一個(gè)直徑130千米的環(huán)形山，取名為赫歇耳(Herschel)，它幾乎是整個(gè)衛(wèi)星直徑的三分之一。赫歇耳的內(nèi)壁大約有5千米高，部分底部深10千米，中央山峰在環(huán)形山中隆起6千米。造成形成這個(gè)環(huán)形山的撞擊一定差點(diǎn)將土衛(wèi)一撞碎。撞擊的反面可看到裂縫，可能就是因?yàn)檫@次撞擊。
表面的環(huán)形山處于飽和狀，但沒(méi)有一個(gè)同赫歇耳一樣大。這表明在土衛(wèi)一的早期歷史中，可能被一個(gè)比創(chuàng)造出這個(gè)環(huán)形山的星體更大的物體撞擊，使新衛(wèi)星完全破裂（抹去當(dāng)時(shí)所有表面撞擊痕跡），但后來(lái)碎片又合并在一起組成了今天的土衛(wèi)一。