This Month’s Sky – February 2015


What’s Up in the Sky
AAA Observers’ February Guide
By Tony Faddoul

February’s Evening Planets: Mars and Venus will be moving from Aquarius the Water bearer to Pisces the Fish. Mars will be up until 8:00 PM while Venus will be down around 7:00 PM. Uranus will be in Pisces the Fish until 10:00 PM, setting earlier every night until 8:00 PM by the end of the month. Bright Jupiter is found between Cancer the Crab and Leo the Lion all night. Neptune will be in Aquarius the Water bearer for about an hour after sunset in the first half of February.

February’s Evening Stars: The Winter Triangle will be up in February until after midnight: Sirius, the brightest star viewed from Earth is in Canis Major the Great Dog, Betelgeuse is in Orion the Hunter, and Procyon is in Canis Minor the Small Dog. Spot Rigel in Orion, Capella in Auriga the Charioteer, Aldeberan in Taurus the Bull, and bright Castor and Pollux in Gemini the Twins. Also find the stars of constellations Cassiopeia, Perseus, Cepheus, Draco, Leo, Cancer, and the two Dippers during the month.

February’s Morning Planets: Jupiter will linger between Cancer the Crab and Leo the Lion until an hour before sunrise. Mercury is in Capricornus the Seagoat during the last half of February for about an hour before sunrise. Saturn is visible in Scorpius the Scorpion after 2:00 AM and until sunrise.

February’s Morning Stars: Couple hours before sun-rise, spot the Summer Triangle of Vega in Lyra the Harp, Deneb in Cygnus the Swan, and Altair in Aquila the Eagle. Look for Capella in Auriga the Charioteer, redish Antares in Scorpius the Scorpion, Castor and Pollux in Gemini the Twins, Arcturus in Bootes the Herdsman, and Spica in Virgo the Virgin, along with the stars of constellations Leo, Hercules, Libra, Cancer, Corona Borealis, Cassiopeia, Cepheus, Draco, and the two Dippers.
February Skylights
Feb 3 Full Moon at 6:08 PM
Feb 4 Jupiter is 5° north of the moon (morning)
Feb 6 Moon at apogee (252,375 miles from Earth)
Feb 6 Jupiter is at opposition, brightest viewed from Earth in 2015
Feb 11 Mercury is stationary
Feb 11 Last Quarter Moon at 10:50 PM
Feb 18 New Moon at 6:50 PM
Feb 21 Uranus is ½ ° south of the moon (at sunset)
Feb 19 Moon at perigee (221, 210 miles from Earth)
Feb 21 Conjunction of Venus and Mars in Pisces the Fish (after sunset)
Feb 25 First Quarter Moon at 12:15 PM

Times given in EDT.


Jupiter at its Brightest in February

The third brightest object in the night sky after the Moon and Venus, Jupiter will be at its brightest this month in opposition (Earth is directly between the Sun and Jupiter). Although opposition occurs roughly every 400 days, on Feb 6 Jupiter and Earth will be their closest until 2019. Venus will be brighter for an hour after sunset, but leaves the rest of the night to -2.6 magnitude Jupiter, found by constellation Cancer the Crab, moving east to west all night.

The Jovian Moons
67 confirmed moons orbit Jupiter. The four largest, Io, Europa, Callisto, and Ganymede, are known as the Galilean moons. They were discovered by Galileo Galilei in 1610 – the first bodies observed to orbit neither Earth nor the Sun. Through a telescope, you can see their shadows as they cross Jupiter. On Jan 23, a rare triple-moon transit occurred. The next one observable from the U.S. won’t happen until Dec 30, 2032.

Ancient Mythology
Jupiter, adapted by Roman mythology from the Greek god, Zeus, was king of the gods. So who are Io, Europa, Callisto, and Ganymede? Well, Zeus had many lovers, much to the chagrin of his wife, Juno (Hera to the Greeks).

Io was a nymph loved by Zeus. To hide her from jealous Hera, Zeus transformed Io into a white heifer. Hera set the hundred-eyed giant Argos to imprison Io, but Zeus sent Hermes to slay him. Left to wander across the land, Io eventually reached Egypt, where Zeus restored her to her original form.

Europa was the beautiful daughter of the Phoenician king of Tyre. Overwhelmed by love, Zeus transformed himself into a magnificent white bull and seduced her. With Europa on his back, he swam to the island of Crete, where she became queen – the continent Europe is named for her. Zeus recreated the bull’s shape in the stars of the constellation Taurus.

Callisto was a nymph that Zeus loved and tried to hide from his wife Hera by changing her into a bear. Her son, Actas, was hunting one day and came across Callisto in the form of bear. Actas accidently killed the bear only to find it was his mother. Zeus placed them together into the sky as the constellations Ursa Major the Great Bear and Ursa Minor Little Bear, commonly known as the Big and Little Dipper.

Ganymede was a handsome Trojan prince desired by Zeus. In the form of an Eagle, Zeus stole him away to Mount Olympus to become cup-bearer to the gods. Zeus consoled the boy’s father with promises his son would be immortal. Hera’s jealousy forced Zeus to send Ganymede to the sky as the constellation Aquarius, the Water Bearer.