The Planets Read Online Free Page A

a pool of soot hiding the bright solar sphere, and the sky deepens to a crepuscular blue, the Sun’s magnificent corona, normally invisible, flashes into view. Pearl and platinum-colored streamers of coronal gas surround the vanished Sun like a jagged halo. Long red ribbons of electrified hydrogen leap from behind the black Moon and dance in the shimmering corona. All these rare, incredible sights offer themselves to the naked eye, as totality provides the only safetime to gaze at the omnipotent Sun without fear of requital in blindness.
    Moments later, the shadow of the Moon passes and the natural world order is restored by the ordinary grace of the Sun’s familiar light. But visions of the eclipse persist among viewers, as though a miracle had been witnessed. Is it an accident that the Solar System’s lone inhabited planet possesses the only satellite precisely sized to create the spectacle of a total solar eclipse? Or is this startling manifestation of the Sun’s hidden splendor part of a divine design?
     
    * Discarded comet dust litters interplanetary space, and when the Earth trundles into a patch of it, the particles that fall through the atmosphere are incinerated, appearing as isolated “shooting stars” or whole showers of meteors.
    * Degrees K, for Kelvin, are the same size as degrees Celsius (or centigrade)—almost double the value of Fahrenheit degrees. However, the Kelvin scale starts lower, at –273º C, or “absolute zero,” the point at which all motion ceases, and has no upper limit, which makes it useful for describing the temperatures of stars.

MYTHOLOGY
    T he planets speak an ancient dialect of myth. Their names recall all that happened before history, before science, when Prometheus hung shackled to that cliff in the Caucasus for stealing fire from the sky, and Europe was not yet a continent but still a girl, beloved by a god, who beguiled her disguised as a bull.
    In those days Hermes—or Mercury, as the Romans renamed the Greek messenger god—flew fleet as thought on divine errands that earned him more mentions in the annals of mythology than any other Olympian: After the goddess of the harvest lost her only daughter to the god of theunderworld, Mercury was sent to negotiate the victim’s rescue, and drove her home in a golden cart pulled by black horses. When Cupid got his wish, making Psyche immortal and therefore fit to marry him, it was Mercury who led the bride into the palace of the gods.
    The planet Mercury appeared to the ancients, as it appears to the naked eye today, only on the horizon, where it coursed the twilight limbo between day and night. Swift Mercury either heralded the Sun at dawn, or chased after it through dusk. Other planets—Mars, Jupiter, Saturn—could be seen shining high in the sky all night for months on end. But Mercury always fled the darkness for the light, or vice versa, and hastened from view within an hour’s time. Likewise the god Mercury served as a go-between, traversing the realms of the living and the dead, conducting the souls of the deceased down to their final abode in Hades.
    Myth may have conferred the god’s name on the planet, because it mirrored his attributes, or perhaps the observed behavior of the planet gave rise to legends of the god. Either way, the union of planet Mercury with divine Mercury—and with Hermes, and the Babylonian deity Nabû the Wise before him—was sealed by the fifth century B.C.
    The persistent image of Mercury, lean and hell-bent as a marathon runner, personifies dispatch. Wings on his sandals urge him on, spurred faster by the wings on his cap, and the magic powers of his winged wand. Although speed tops the panoply of his powers, Mercury also gained fame as a giant-killer (after he slew thousand-eyed Argus) and as the god of music (because he invented the lyre, and his son, Pan, fashioned the shepherd’s pipe of reeds), god of commerce and protector of traders (for which he is remembered in words like