Rover View of Earth



Many people believe that astrology only concerns the sun. This is due to the Western world view of astrology, which has taken on the form of Zodiac horoscopes. However, in truth the study of astrology goes well beyond sun signs. Comets are really traveling relic icy planetesimals, the remnants of what was once a vast population of ancient objects that contributed to the construction of the quartet of giant, gaseous planets of the outer Solar System: Jupiter, Saturn, Uranus, and Neptune. Alternatively, the asteroids--that primarily inhabit the region between Mars and Jupiter termed the Main Asteroid Belt--are the leftover rocky and metallic planetesimals that bumped into one another and then merged together to form the four rocky and metallic inner planets: Mercury, Venus, Earth, and Mars. Planetesimals of both the rocky and icy kind blasted into one another in the cosmic "shooting gallery" that was our young Solar System. These colliding objects also merged together to create ever larger and larger bodies--from pebble size, to boulder size, to mountain size--and, finally, to planet size. The scientists also considered other possible sources of hydrogen from the little moon itself, such as a preexisting reservoir in the icy crustal shell or a global ocean. Subsequent analysis indicated that it was unlikely that the observed hydrogen was obtained during the formation of Enceladus or from other processes on the moon-world's surface or in the interior.