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The Sky This Week, 2016 January 27 - February 2

Lest we forget.
Dome of the Kaj Strand 1.55-meter (61-inch) Astrometric Telescope
Naval Observatory Flagstaff Station, Arizona.
Yes, we're snowed in at both of our sites!

The Moon wanes in the morning sky this week, passing through the rising stars of the springtime sky. Last Quarter occurs on the 31st at 10:38 pm Eastern Standard Time. Luna may be found near the bright planet Jupiter as they both rise late in the evening of the 27th. Luna will pass about four degrees north of the bright star Spica before dawn on the 30th. Pre-dawn skywatchers can see the Moon just two degrees north of ruddy Mars on the morning of February 1st.

For those of us still digging out from the big east coast snow storm of the past week, there is reason to hope. February 2nd marks the approximate mid-point of the astronomical season of winter, a calendar marker known as a "cross-quarter" day. Thanks to a cultural tradition imported to the United States by early German settlers in Pennsylvania, the date is now almost universally recognized as "Groundhog Day". The date has ties to the ancient Celtic observance of "Imbolc", the date that they considered the traditional beginning of spring. It is also the time of year when the increasing length of daylight is obvious, indicating the certain return of the Sun and warmer weather. With the Christianization of the pagan Celts, Imbolc became associated with the Feast of Saint Birgid and the observance of Candlemas, the date marking 40 days after Christmas. Its association with weather dates to both German and Celtic traditions, each of which has a variation on the saying "If Candlemas be fair and bright, Winter has another flight. If Candlemas brings clouds and rain,

Winter will not come again." For snow haters, rest assured that as far as the stars are concerned, the equinox falls just over six weeks after Groundhog Day, so take heart, the end is in sight!

On a more somber note, this final week of January marks the anniversaries of three tragedies in the quest for space exploration. 49 years ago on January 27 a fire during a ground test claimed the lives of the crew of Apollo 1 as they prepared for the first flight of the hardware that would eventually carry us to the Moon. 30 years ago on January 28 the crew of the Space Shuttle "Challenger" perished in an explosion caused by a faulty seal in a solid rocket motor segment. 13 years ago on February 1st the crew of Space Shuttle "Columbia" died when the shuttle orbiter disintegrated during re-entry. The cause of the breakup was traced to a piece of foam insulation that fell off of a fuel line and punctured the leading edge of one of the orbiter’s wings during launch. Those of us who look to the skies share the sense of wonder and exploration that our view of the cosmos affords us; the men and women who undertook these flights were all reaching to achieve the same goal of expanding human knowledge to the edges of the vast space around us. May they rest in peace. Their names live on in features on the Moon, Mars, and even the distant stars.

The giant planet Jupiter now beckons in the late evening sky as he rises just before 9:00 pm. On the evening of the 27th he rises in the company of the Moon, adding his light to that of the waning gibbous to light the snow-covered environs of Washington. If you stay up late you can get a decent look at Old Jove by midnight as the planet climbs higher in the sky. Jupiter’s ample disc will show considerable detail to small-to-moderate aperture telescopes.

Mars rises at around 1:00 am and also receives a visit from the waning Moon. If you’re up before dawn on the morning of the 1st, you’ll fine Mars just below Luna’s half-illuminated disc. The red planet presents a small pink-hued gibbous disc to the telescope owner, and you’ll need exceptionally steady air to eke out much detail on his dusty surface. However, we’ve had a plucky robotic explorer up there for quite some time. The "Opportunity" Mars Exploration Rover, designed to last 90 days on the planet’s surface, has just passed 12 years of operation!

Saturn can be found low in the southeastern sky at dawn, rising among the stars of the summer constellation of Scorpius. Look for a nice color contrast between Saturn’s golden hue and the ruddy complexion of Scorpius’ brightest star, Antares.

Venus and Mercury rise with the beginning of morning twilight. You’ll need a flat, open horizon to the southeast to get a good look at them as the sky brightens. By week’s end the duo are about five degrees apart with Venus being a bit higher. You’ll probably need binoculars to spot elusive Mercury, but Venus should catch your eye up until the moment of sunrise.

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