Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during February 2014.

Orion the Hunter is just to the west of south in the evening, the three stars of his Belt pointing up towards Taurus the Bull, which contains the Hyades and Pleiades Clusters. Gemini lies above, with the planet Jupiter resident there this month. Following Orion's Belt downwards leads to the brightest star in the night sky, Sirius, in Canis Major. If you scan down and left from Sirius, you come to the open cluster M41, which hosts a single red giant star among its blue population. Canis Minor and its bright star, Procyon, are towards the south, while Cancer, home to the Beehive Cluster, is in the south-east. Leo the Lion is rising in the east, with its bright star, Regulus. The Realm of the Galaxies, a rich area of the sky between Leo and Virgo, rises later in the night, looking towards the Virgo Galaxy Cluster. Ursa Major, the Great Bear, is in the north-east, while Auriga and its yellow star, Capella, are above Taurus. Cassiopeia and Perseus are in the north-west, with the Milky Way running between them and the Perseus Double Cluster visible in binoculars.

The Planets

• Jupiter is in the latter part of an excellent apparition. Shining at magnitude -2.6, it was at opposition (opposite the Sun in the sky) in early January. At the beginning of this month, it reaches 40 degrees' elevation by 19:00 UT (Universal Time) and over 60 degrees by 22:00. It gets to its highest nightly elevation at around 20:30 by month's end. Jupiter is moving retrograde (westward) in Gemini, approaching the star Mebsuta. A small telescope shows the four Galilean moons and, at the right times, the Great Red Spot on the planet's surface.
• Saturn is a pre-dawn object, rising around 02:00 UT at the beginning of the month and 00:30 at the end. It lies in Libra and has a magnitude of +0.4 and a disc 17" across. The rings are 38" across and 23 degrees from the line of sight, allowing features such as Cassini's Division to be seen with a small telescope. A larger telescope, perhaps 200mm in aperture, may allow the Enke Gap to be spotted in still atmospheric conditions. The only disadvantage is that Saturn's elevation is not very high for northern hemisphere observers.
• Mars is in Virgo, rising around 23:30 UT at the beginning of the month and around 22:30 by month's end. During February, it brightens from +0.2 to -0.5 in magnitude and grows from 9 to 11" in angular size, and its illumination of 91 percent allows surface features to be seen. The dark V-shape of Syrtis Major is a prominent one, while the white Northern Polar Cap may be slightly less obvious in the Martian summer. Mars progresses down through Virgo during the month, starting off 5 degrees to the upper left of the bright blue star Spica, and ending 6 degrees to its left as it begins moving retrograde (westward).
• Mercury reached eastern elongation (its greatest separation of 18 degrees from the Sun in the sky) on the 31st of January. It lies 8 degrees below a crescent Moon on the 1st of this month, with a brightness of magnitude -0.6 and an angular diameter of 7", and can be seen for up to 2 hours after sunset if you have a low western horizon. This reduces to 1.5 hours by the 7th, when the magnitude is +1, the angular size is 8" and 20 percent of the disc is illuminated. Mercury is quickly lost from view after this, reaching inferior conjunction (between the Sun and the Earth) on the 15th. It reappears in the pre-dawn sky at month's end, about 20 degrees to the west of the Sun, but its very low elevation makes it difficult to spot.
• Venus passed inferior conjunction on the 11th of last month, and commences this month low in the east before dawn. Shining at magnitude -4.6, it reaches 17 degrees' elevation in the south-east at sunrise by the middle of the month, showing a crescent of 25 percent illumination with an angular diameter of 46". Venus concludes February 36 percent illuminated and 33" across.

Highlights

• It is a great time to observe Jupiter in the evening this month. You can see many features through a small telescope: the North Equatorial Belt is broader than it was a few years ago, and the Great Red Spot more prominent in the South Equatorial Belt - as long as you know when to look.
• Mercury is close to a thin crescent Moon on the night of the 1st to 2nd, and the scene may be accompanied by earthshine.
• Jupiter is about 7 degrees from a waxing Moon on the evening of the 10th.
• Mars is 5.5 degrees above and left of the star Spica and 10 degrees from a waning Moon before dawn on the 19th.
• The second-largest asteroid in the Asteroid Belt, Pallas, can be found for a few days around the 22nd as it approaches the 2nd-magnitude star Alphard in Hydra. It reaches opposition (opposite the Sun in the sky) on the 22nd, putting it due south around midnight. At magnitude +7, it is easily visible in binoculars - find Alphard first, and the asteroid should be in the same field of view (4 degrees away on the 22nd). Pallas is some 550 kilometres across (although non-spherical), and on the 22nd it lies 2.1 times further from the Sun than does our own planet.
• Venus is just 0.5 degrees above a thin, waning crescent Moon before dawn on the 26th. The pair can be seen in the south-east.

Southern Hemisphere

John Field from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during February 2014.

The evening sky is dominated in the north by the planet Jupiter and the constellations of Orion, Canis Major and Taurus. Jupiter, looking like a bright, white star, is in front of the distant stars that form the constellation of Gemini, the Twins. Gemini is one of the constellations through which the Sun moves as seen from the Earth; the path of the Sun across the sky is called the ecliptic, and the constellations along it form the zodiac. To the left of Gemini is an upside down 'V' of stars that forms the head of another zodiacal constellation, Taurus the Bull. The brightest of these stars is the giant, orange-hued Aldebaran, while its younger, fainter companions belong to more a distant cluster called the Hyades. Another star cluster called the Pleiades marks the Bull's back, and can be found to the west of his head. Visible as a compact cluster to the naked eye, they make a fine sight in binoculars.

Gemini and Cancer are two of the other zodiacal constellations in the summer sky. The bright stars Castor and Pollux mark the heads of the Twins, and can found in the north after sunset. Gemini lies on the eastern edge of the Milky Way, and faint and distant stars can be seen around the two main stars. Five faint galaxies can be found within 1 degree of Castor using a large telescope. Pollux is the brighter of the two stars. Near to the star Eta Geminorum is M35, an open star cluster. Under good conditions it can be seen with the unaided eye as a hazy star, while binoculars or a wide-field telescope present an even better view. Cancer the Crab is a fainter constellation of five stars, at the centre of which is a cluster of stars called Praesepe, or the Beehive. Large and bright, it appears as a nebula to the unaided eye, and binoculars reveal individual stars within the cluster. Galileo viewed this cluster with his telescope in 1610, becoming the first human to see it as a group of stars.

Orion the Hunter, an upside-down summer constellation in the southern hemisphere, is due north after sunset. His brightest stars, Rigel, Betelgeuse and Bellatrix, along with the three stars of his Belt, form an easily recognisable pattern. The Orion Nebula can be found in the middle of Orion's Sword, appearing as a fuzzy star to the unaided eye. Binoculars or a small telescope show a bat-shaped cloud, while a telescope of 100 millimetres or more in aperture reveals a number of stars in and around the nebula, including a tight group of four stars called the Trapezium. Above the Belt is Rigel, the brightest star in Orion, which is actually a triple system. To the east are Orion's two hunting dogs, Canis Major and Canis Minor. The brightest star in the night sky, Sirius, marks the collar of Canis Major, and the Large Dog is upside-down with his feet in the air. Below Canis Major is Procyon, forming the tail of Canis Minor, while a fainter star to the left marks the Small Dog's front. With binoculars, two lovely sights are visible: just over a third of the way between Sirius and Procyon is a cluster of stars called M50, and halfway along the line from Procyon to Betelgeuse is a rectangular cluster of stars embedded in a faint nebula called the Rosette. Almost overhead in the early evening is the second-brightest star in the night sky, Canopus.

The Planets

• Mars rises in the east around midnight, and is in the constellation of Virgo.
• Saturn rises in the east some time after Mars, and lies in Libra. Like Mars, it will be better placed for viewing in the evening sky during autumn and winter.
• Venus reappears in the morning sky this month, climbing higher as the month progresses.
• Mercury also becomes visible in the pre-dawn sky towards the end of the month.