Facing south, looking almost straight up, November
15th at 9:30 p.m.
Save our starry night skies
Be a considerate neighbor: Reduce nighttime glare.
Shield all your outside lights downward (or turn them off completely)
and enjoy the beautiful, starry night sky.
The cool, crisp fall nights are great for observing the night sky,
so dress warmly and venture outside to enjoy the view.
At about 9:30 p.m. this month, you will find Pegasus flying high
overhead. The body of the horse consists of four stars in a square
pattern just south of straight up: Algenib, Markab, Scheat, and
Alpheratz. Actually, Alpheratz is shared with the constellation
Andromeda and is considered the brightest star in Andromeda. The
front legs are formed by two crooked lines of stars, leading from
Scheat to the west and north. Another meandering line of stars from
Markab to Enif forms the neck and head and snout. Parts of Andromeda
leading from Alpheratz to the northeast depict the hind legs.
In 1995, the first extrasolar planet circling a sun-like star was
found around 51 Pegasus. Observations showed that the planet orbits
very close to the star, suffers estimated temperatures around twelve
hundred degrees Celsius, and has a minimum mass about half that
IK Pegasus, or HR 8210, is a binary star about one hundred-fifty
light years from the Sun. It is just barely bright enough to be
seen with the unaided eye. The smaller star in this binary is a
massive white dwarf. It is the closest known candidate that could
produce a supernova. When the larger star evolves into a red giant,
its radius is expected to balloon out to a radius where the white
dwarf can siphon matter from the expanded gaseous envelope. When
the white dwarf approaches the Chandrasekhar limit of 1.44 solar
masses, it may explode as a Type Ia supernova. However, in the time
it will take for the system to go supernova, it will have moved
a considerable distance from Earth and will pose no threat. A supernova
would need to be within about twenty-six light years of the Earth
to significantly impact our biosphere.
In Greek mythology, Pegasus was a winged horse. He was the son
of Poseidon and Gorgon Medusa. Athena caught and tamed Pegasus,
and presented him to the Muses at Mount Parnassus. After he became
the horse of the Muses, he was at the service of the poets. Later,
Pegasus aided the hero Bellerophon (also known as Perseus) in his
fight against both the Chimera and the Amazons.
Another story tells that the Bellerophon was told by Polyeidos
to sleep in the temple of Athena, where the goddess visited him
in the night and presented him with a golden bridle. The next morning,
still clutching the bridle, he found Pegasus drinking at the Pierian
spring. When the steed saw the bridle, he approached Bellerophon
and allowed him to ride. Bellerophon slew the Chimera on Pegasus’
back, and then tried to ride the winged horse to the top of Mount
Olympus to see the gods. However, Zeus sent down a gadfly to sting
Pegasus, causing Bellerophon to fall back to Earth, where he lived
out his life in misery as a blinded cripple as punishment for trying
to act as a god. Afterward, Pegasus found sanctuary on the sacred
mountain, where he carried Zeus’ thunderbolts and was ridden
by Eos, the goddess of dawn.
THE PLANETS AND MOON
• Mercury will make an appearance this month east-southeast.
Look for the thin crescent Moon near the horizon. On the 8th, about
forty-five minutes before sunrise, Mercury will be above and to
the left, while the star Spica will be above and right. Bright Venus
will hover about thirty degrees above the horizon. Arcturus can
also be to the left of Venus.
• Venus will shine brightly in the early morning sky. You
can’t miss it in the southeast. On the 5th, look for Venus
near the Moon before sunrise. Then, two hours after sunrise, use
binoculars to find the Moon again and see the planet Venus in daylight.
• Mars can be found in the northeast after sunset. On the
26th, about two and a half hours after sunset, watch the Moon slowly
slide past Mars over the course of the evening. Castor and Pollux
are to the left of the Moon while Capella is about thirty degrees
above the Moon.
• Jupiter is low in the southwest at sunset. You can briefly
spot a crescent Moon below Jupiter about forty-five minutes after
sunset on the 12th.
• Saturn is in the southeast before sunrise. On the 4th,
look for a spectacular lineup one hour before sunrise. The star
Spica and Mercury will be very low in the east-southeast. Then,
on an arching line, Venus will be higher in the southeast followed
by the Moon, Saturn, and finally the star Regulus in the south-southeast.
• The Moon is new at 5:33 am MST on the 9th and full at 7:70
a.m. MST on the 24th.
If you have a question or comment for Charlie,
you may email him at: firstname.lastname@example.org.