Comet
McNaught, discovered last August, has become one of the greatest
comets of the last century. The comet was an extravagant object.
Down under, McNaught was bright, clearly visible, and occupied
a huge portion of the evening sky through the middle portion
of January 2007.
Comet
McNaught was visible from the northern hemisphere during the
first half of January 2007, but observers at higher latitudes
over Alaska, Canada, and the northern states were favored to
see it. In the days leading up to the comet’s closest
approach to the sun on January 15th, it brightened dramatically.
For several days around January 10, the comet should have been
bright enough to be observed immediately above the west Texas
horizon at sunrise and sunset. In fact, it brightened so much
that it was visible in broad daylight over North America from
roughly the 13th to the 15th of this month. Increasing clouds
and even an ice storm, however, restricted its visibility over
the South Plains. Comet McNaught then slipped into the southern
hemisphere sky on the 16th, and all hope for observing the comet
from west Texas was lost…or was it?
During
the evening of the 16th, an amateur astronomer in Colorado observed
an unexpected and amazing sight. The comet’s tale had
become so enormous, that it actually curved northward along
McNaught’s recent path, and remained visible in the evening
sky over the northern hemisphere. During mid-January, astronomers
and enthusiasts located in the northern hemisphere worldwide
observed the northern end of McNaught’s tail, as it appeared
from our earthly perspective, to curve around the globe. Sky
and Telescope Magazine reported that such a phenomenon has not
been documented by astronomers since the year 1744.
As
the clouds cleared in the wake of the winter storm on Saturday,
20 January 2007, National Weather Service meteorologist Todd
Lindley photographed Comet McNaught’s tail from Frankford
Avenue, just south of FM1585. The tail was visible to the un-aided
eye around 730 PM CST as a diffuse colorless glow that arced
from the southwestern horizon up toward the north, some 30 degrees
above the horizon. Faint streamers were visible within the tail.