Download PISGAH Text by Dr. Bob Hayward ASTRONOMICAL Astronomer

PISGAH
ASTRONOMICAL
RESEARCH
INSTITUTE
Text by Dr. Bob Hayward
Astronomer/Educator
Starmap by TheSky
Software Bisque
Mountain Skies
January 4, 2016
ORION IS RISING IN THE EAST
The stars: Winter is truly here now, marked for the astronomer, not by the errant snow shower,
but by the inevitable appearance of Orion the hunter in the evening skies. Orion dominates the skies in
the winter as does no other constellation in any other season. With his seven bright stars, especially
the three in a row that mark his famous belt, he is easily spotted as he rises in the east in the early
evening. The three bright stars of his belt form a conspicuous line. From east to west they are Alnitak,
Alnilam and Mintaka.
To the north of his belt lie his shoulders in the bright red supergiant star
Betelgeuse to the east and fainter Bellatrix as his western shoulder. To the south are his knees marked
by Saiph on the east and the blue-white Rigel on the west.
Look closely at the three fainter
stars hanging below his belt. This is the
sword of Orion. Gaze in particular at the
middle star and you will notice it is a bit
fuzzy; it is called the “smoking star” in
some Native American traditions. A pair
of binoculars or a telescope reveals this
to be the beautiful “Great Nebula of
Orion,” an immense cloud of gas in
which stars are currently forming. To the
astronomer this nebula is known as
Messier 42 or M42 since it was object
no. 42 in a catalog of faint, fuzzy objects
compiled a little over 200 years ago by
the French comet hunter Charles Messier. His catalog, ironically, was a list of objects not to look at if
you were looking for comets. Generally, when comets are first discovered optically, they appear as
faint, fuzzy objects that move against the pattern of background stars. The objects in Messier’s catalog
looked very much like comets but didn’t move! Now the Messier objects are famous as nebulae,
galaxies and star clusters.
The planets: Four of the five classical or naked-eye planets are in the predawn skies as they
have been since early December. But Mercury is now in the evening skies just for this week. Look for
it low in the southwest as the sun sets. On January 14 this elusive planet passes through inferior
conjunction on a path a little bit above the sun to reappear in the morning skies later this month.
Mercury, being the closest planet to the sun, moves very quickly. By April it will have passed through
its predawn phases, passed behind the sun in superior conjunction and will again be in our evening
skies after sunset. Then, on May 9 it once again reaches inferior conjunction; but this time it will be
exactly in line with the sun and observers in the Carolinas, with proper eye protection, will be able to
observe the planet transit or pass in front of the sun that morning. More details closer to the event.
The other four planets are in the evening skies now and when Mercury joins them in midJanuary, we will have all five of the classical planets in view before dawn. Jupiter is now rising about
an hour before midnight so, by dawn it is well up in the south. Since it is brighter than any nighttime
star, it is easily spotted under the tail of Leo the lion. Rising about 1 a.m. EST the red planet Mars is in
Virgo close to the bright star Spica. By dawn, Mars is also well up in the south but more to the east
than Jupiter. The moon tonight lies right smack in the middle of Libra the scales and to its east, in the
head of the scorpion, are Venus and Saturn. Of course the moon moves around the earth in a month
and for the next two nights forms a nice grouping with these two planets. Soon the moon will disappear
from the morning skies as it heads to new moon on Saturday night. That same night the two planets in
the scorpion put on a show of their own. Venus which is much closer to the sun that Saturn the old
man of the planets is moving rapidly downward with each successive morning. On Friday night it will
pass by the slower moving Saturn; thus, by the time these two planets rise, they will be very close
together just to the left of Antares the fierce red heart of the scorpion.
Celestial Calendar:
January 9, predawn – Venus less than the diameter of the moon north of Saturn
January 9, 8:31 p.m. EST – New Moon
January 16, 6:26 p.m. EST – First Quarter Moon
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PARI is a public not-for-profit public foundation established in 1998. Located in the Pisgah National
Forest southwest of Asheville, NC, PARI offers educational programs at all levels, from K-12 through postgraduate research. For more information about PARI and its programs, visit www.pari.edu. Follow PARI on
Twitter at http://twitter.com/Astronomy_PARI. “Like” PARI on Facebook at
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For further information or questions about this Mountain Skies column, contact Dr. Bob Hayward at
[email protected]. Graphics produced with TheSky Astronomical Software, Software Bisque.