Comet heads back out
By Vernon Whetstone
Astronomers around the world held their collective breath last week on Thanksgiving Day as Comet ISON took its turn around the Sun to head back out into the icy depths of the solar system, to the Oort Cloud, where it came from more than a million years ago.
Although the comet had never quite lived up to some of the predictive hype of becoming the “Comet of the Century,” it was becoming a bright object for pre-sunrise viewing during the past week and there were high hopes that now having turned that it would become brighter.
When the comet failed to appear at the predicted time hopes began to fall in fear that the comet’s body had indeed succumbed to the gravitational power and extreme temperatures of the Sun and been destroyed.
Several hours later Sun-watching satellites began to show a much smaller object that was traveling away from the Sun in the predicted orbital path ISON should have been taking. It would seem that ISON had survived in some perhaps reduced form sort of like the Phoenix rising from its own ashes to assume once again the guise of its predecessor.
I thought that now the comet, while not living up to the expectations of a “Comet of the Century,” should be renamed as “The Little Comet That Could,” after the little engine that overcame adversity and achieved success in its efforts.
Now, where was I?
Oh yes, what else is up there? Tonight, Wednesday, Dec. 4, a very slender two-day old crescent moon will be snuggled right up next to the planet Pluto. Well, I say “snuggled up,” but that is not really the case.
While the moon is some 250,000 miles away from Earth, Pluto, out in the outer reaches of the solar system, is more like 4.67 million miles from Earth on average. They only look close because they are along the same line of sight.
But I need to qualify that again because you really can’t see Pluto without using a really ginormous telescope, and even then you would need to take photographs over several nights to see what moved.
While you are out looking at the moon, be sure to look for some Earthshine, or sunlight reflected off of Earth back onto the non-lit portion of the moon. The effect is enhanced in binoculars.
Since we are all outside about an hour after local sunset, also take a look high in the western sky for the Summer Triangle of Vega, Altair, and Deneb still hanging in the sky.
Speaking of the moon, let’s follow it for the next several evenings as it passes some other interesting astronomical objects.
On Thursday, Dec. 5, a slightly thicker moon will be near the very bright planet Venus in the southwestern sky, and on Saturday, Dec. 14, an almost full moon will be near the Pleiades star cluster.
SKY WATCH: New moon, Dec. 2, first quarter Dec. 9. Jupiter is rising earlier in the evening and will be view-able around 8:30 p.m. local time in the eastern sky.
NEXT WEEK: Gift ideas for the more experienced astronomer.