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The Sky This Week, 2018 January 30 - February 6

Will he or won't he? Only the groundhog knows for sure!
Messier 42, the Great Orion Nebula, 2016 December 31
imaged from Mollusk, Virginia with a 10.2-cm (4-inch) f/6.5 Explore Scientific AR102 refractor
and a Canon EOS Rebel T2i DSLR

The Moon wanes from the early morning total eclipse that ends the month of January and moves into the morning sky this week.  During the week she moves through the rising stars of the springtime sky.  Last Quarter occurs on the 7th at 10:54 am Eastern Standard Time.  Look for Luna just east of the bright star Regulus when the two rise in the late evening of the 1st.  She will pass north of the bright star Spica in the gathering twilight on the morning of the 5th.  You’ll find her perched west of bright Jupiter before dawn on the 7th.

In addition to the “Super-Blue-Blood” Moon that we discussed last week, this week holds yet another interesting astronomical phenomenon.  Most of us associate February 2nd with the observance of “Groundhog Day”, waiting with bated breath to see if a large rodent indigenous to the eastern U.S. emerges from its burrow to forecast the remaining duration of winter.  Few of us know the origin of this quaint observance, though.  The tradition came to America with German immigrants who settled in Pennsylvania in the mid-1800s.  They associated the appearance of badgers with the feast of Candlemas, which marked the first 40 days after Christmas.  If the badger emerged from its den on a bright sunny day the cold of winter would last another four weeks.  The transplanted tradition stretched this to six weeks in the colder environs of Pennsylvania, and the badger of Europe was replaced by the groundhog.  The association of Candlemas with the duration of winter can be found in many European traditions, but not necessarily associated with observing animal behavior: “If Candlemas is fair and clear there’ll be two winters in the year”.  So where’s the astronomical connection here?  Candlemas was associated with a seasonal marker known as a “cross-quarter” day that marked the mid-point of an astronomical season.  There are three other such dates in calendars which are still observed in various traditions.  Of these, Halloween is probably the most widely observed in popular culture.  

The bright Moon washes out all but the bright stars of the Great Winter Circle early in the week, but by the weekend you’ll have a few hours to enjoy the flashy winter constellations in all of their glory.  My favorite star pattern is, of course, Orion, and it is well worth the effort to get out into the country to view The Hunter in all of his glory.  He cuts a magnificent figure in the sky, and when you see him associated with his fainter stars it’s no wonder that he held a prominent place in the skylore of civilizations throughout history.  If you have binoculars, pan over the constellation and marvel at the color of his stars.  Take some time to look at the small asterism that seems to hang from Orion’s “belt”; the center star shows pronounced “fuzziness” that betrays the Great Orion Nebula, one of the most interesting sights for the small telescope in the entire sky.  The nebula is the bright central part of a huge cloud of glowing gas and dust that pervades the entirety of the sky behind the constellation.  It is a vast stellar nursery, and astronomers are now able to watch new-born stars evolve with instruments like the Hubble Space Telescope.

The bright planets are still clustered in the pre-dawn sky.  You’ll find Jupiter the easiest spot, close to the meridian as twilight brightens the sky.  Mars follows Old Jove by a bit over 10 degrees and is now pressing eastward above the rising stars of Scorpius.  The red planet is gradually brightening and is now about the equal of the Scorpion’s brightest star Antares.  Compare the colors of these two objects and you’ll appreciate why Antares means “Rival of Mars”.   Saturn completes the planet parade, and may be found very low in the southeastern sky an hour before sunrise.

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