Carnegie Skywatch
The January and February Night Skies
The Winter Milky Way
You may notice that each Star Map in Carnegie Magazine
contains a band labeled "Milky Way." This name refers not only to
our home galaxy, but also to the faint band of white light that surrounds
the Earth. The band is the result of the combined glow of billions of stars
near us in the disk of the galaxy seen edge-on. During winter, the Milky
Way is high in the sky in the evening. We are looking toward the edge of
our galaxy. Since we are located on the inner part of a spiral arm, we
are also looking into it. Spiral arms contain bright stars. Thus the winter
evening sky contains the greatest concentration of bright stars seen during
the evening than during any other season of the year. We are looking into
the Orion arm, which contains the bright stars of that constellation, such
as Rigel and Betelgeuse. Sirius, the brightest star in the night sky, is
also found in this arm.
A Total Solar Eclipse
On February 26, the moon will pass in front of the sun and produce a total
solar eclipse visible within a narrow path crossing the Galapagos Islands
and several Caribbean islands. A partial eclipse will be visible from Pittsburgh,
with the northern portion of the moon covering about 15% of the sun's diameter
at maximum eclipse (1:09 pm EST). Do not look directly at the eclipse.
It can cause vision damage. To view the partial eclipse safely, use indirect
methods. One method is to use two index cards. Poke a small hole in the
center of one card. While facing away from the sun, hold this card toward
the sun and project the sun's image onto the face of the other card. Another
method is to cover a small mirror with paper, leaving a small portion of
the mirror exposed. Then carefully reflect the sun's image off this exposed
area onto the surface of a wall. A third indirect method is to project
the sun's image through the eyepiece of a telescope onto a large white
card held in front of the eyepiece.
The Planets
At dusk during early January, Venus can be seen shining brightly low in
the WSW, with faint Mars and bright Jupiter to its upper left. Appearing
lower each evening, Venus eventually disappears into the solar glare, ending
its current evening apparition. Venus passes between the Earth and the
sun on January 16 and will emerge from the solar glare into the dawn sky
during late January. Venus starts out its new morning apparition low in
the ESE. The planet appears higher in the sky each morning throughout February.
The waning crescent moon passes Venus on January 26 and February 23. Venus
will be visible in the morning into mid-September this year.
As Venus disappears into the evening twilight, Mars approaches
Jupiter. Mars will pass 0.2 degrees south of Jupiter during the evening
of January 20th. (As a comparison, the moon's diameter is about 0.5 degrees.).
On this date, the two planets lie nearly along the same line of sight as
seen from Earth, with Jupiter well beyond Mars. This alignment makes for
the closest planetary conjunction of the year. Thereafter, the two planets
appear to pull away from each other in the sky. Mars remains an evening
planet through mid-March. The waxing crescent moon passes close to Mars
on January 29 and February 27.
Jupiter appears lower in the sky each evening, disappearing into the
solar glare during early February. The waxing crescent moon appears close
to Jupiter on January 1 and above the planet on January 29, with Mars close
to the upper left of the moon that evening. Jupiter passes on the far side
of the sun on February 23 and will reappear in the morning sky along with
Venus toward the end of March.
Saturn begins the year high in the south at dusk. The moon appears close
to Saturn January 4 and 5, February 1 and 28, and March 1. On the evening
of February 1, Saturn and the moon can be seen far to the upper left of
Mars and Jupiter. Thereafter, watch the gap close between Saturn and Mars.
By the end of February, the two planets will be 21 degrees apart, with
the crescent moon between them.
Mercury can be seen low in the SE at dawn through late January. At 45
minutes before sunrise, Venus appears 12 degrees to the left of Mercury
on January 22.
Earth is at perihelion, its closest distance to the sun for the year,
on January 4. The Earth will be 91.3 million miles from the sun on that
day.
Moon Phases
First Quarter:
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Jan. 5, 9:19am; Feb. 3, 5:54pm
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Full:
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Jan. 12, 12:25pm; Feb. 11, 5:24am
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Last Quarter:
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Jan. 20, 2:41 pm; Feb. 19, 10:28am
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New:
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Jan. 28, 1:02am; Feb. 26, 12:27pm
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For current information on astronomical events, call the Skywatch Hotline
at 237-3400, then press 1-3-4 within the menuing system.
Planetarium Shows
Be sure to visit the Henry Buhl, Jr. Planetarium at Carnegie Science Center
this winter. Our main feature is Flashback to the Future: 40 Years of Space
Exploration . . . and Counting! Every Friday at 4:00 p.m., the planetarium
presents Stars Over Pittsburgh as your weekly guide to the current night
sky.
Jenny Pon is astronomer and Digistar system manager for the Henry
Buhl, Jr. Planetarium & Observatory at Carnegie Science Center.
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