Titlebook: Astronomy in Depth; Gerald North Book 2003 Springer-Verlag London 2003 astronomy.black hole.cosmology.earth.moon.planet.quasar.solar syste

勤勞

Violent Stars,G. up at the starlit sky on most evenings, we feel that the heavens are unchanging and serenely peaceful. However, just once in a while we may see something to remind us that this impression is far from true.

少量

Obscure

Expertise

diskitis

The Planet Saturn,km and a mass 95 times that of the Earth. The average density of Saturn is a mere 700 kg/m.less dense than water. Saturn moves through the Solar System at a mean distance of 1400 million km from the Sun, taking 292 Earth-years to complete one orbit.

否認(rèn)

The Twilight Zone of the Solar System,ar System consisted of just these five planets plus the Earth, the Sun and the Moon. Then, in 1781, the academic world received a rude shock when an amateur astronomer discovered another planet with his home-made reflecting telescope!

vanquish

The Comets,mets used to be regarded as the portents of doom and tragedy and many a bright comet has caused widespread panic. For instance, a bright comet caused alarm in the England of 1665, in the early weeks of the Great Plague. Another appeared in 1666 just before the Great Fire that was to purge the plague-swept London.

小隔間

endocardium

獨(dú)輪車