SKY REPORTER: January 2013 main content.

SKY REPORTER: January 2013

by Steve Beyer on


Sky Data

On New Year’s Day, sunrise is at 7:20 a.m. Eastern Standard Time. That evening the Sun, located in the constellation Ophiuchus, sets at 4:39 p.m.

Tuesday January 15th, sunrise is at 7:18 a.m. and sunset occurs at 4:53 p.m.

On the last day of the month, Thursday the 31st, the Sun is in Capricorn, rising at 7:06 a.m. and setting at 5:12 p.m. The altitude of the sun at solar noon, its maximum daily elevation, increases during January from 27 degrees of arc on the first to 33 degrees on the 31st. This change results in an increase in duration of daylight during January from nine hours 19 minutes on New Year’s Day to 10 hours and six minutes on the last day of January.

During January average overnight temperatures recorded in Central Park drop from 28 degrees Fahrenheit on the first to 27 degrees on this month’s last day.

Principal Phases of the Moon are:

Last Quarter January 4 at 10:58 p.m. ET
New Moon January 11 at 2:44 p.m.
First Quarter January 18 at 6:45 p.m.
Full Moon January 26 at 11:38 p.m.

Sky Cast

Mercury is low in the predawn eastern sky at the start of January. It rises at 6:45 a.m. in Sagittarius on the first of the month, just 35 minutes before sunrise. It is at superior conjunction with the Sun Friday January 18, after which Mercury moves east of the Sun into the evening sky. On the last day of January Mercury is within boundaries of the constellation Capricorn and sets at 5:56 p.m., 44 minutes after the Sun.

Venus is bright, although rather low, in the southeast during early mornings of January. It rises at 5:49 a.m. in the constellation Ophiuchus on the morning of New Year’s Day. On the last day of January Venus rises at 6:27 a.m. in Sagittarius.

Mars continues to be seen low in the southwestern evening sky. On the first of the month it’s in Capricorn and sets at 6:31 p.m. At month’s end Mars has moved into Aquarius setting at 6:35 p.m.

Jupiter remains in Taurus near first magnitude star Aldebaran and the “V” shaped Hyades open star cluster. The big planet is a vivid highlight to beautiful star fields of winter nights. On January first Jupiter sets at 4:55 a.m. and at month’s end it leaves our sky at 2:51 a.m.

During January Saturn is in Libra. On the first of the month the sixth planet from the Sun rises above the east-southeastern horizon at 2:24 a.m. and on the morning of the 31st it rises at 12:34 a.m.

Sixth magnitude Uranus is in Pisces. On the first night of 2013 it sets at 11:34 p.m. and by month’s end it will set at 9:40 p.m.

Neptune remains in Aquarius setting at 8:44 p.m. on January 1st, and at 6:51 p.m. on January 31st.

The Earth is at perihelion, its annual closest point to Sun, late on the night of January first. At that time our distance to the Sun is about 91,407,000 miles.

The Quadrantid Meteor Shower peaks during the night of January 3rd and early morning of the 4th. This shower’s radiant is near the star Alkaid at the end of the Big Dipper’s handle. However moonlight will be present after midnight this year and will interfere with viewing these meteors. This and all meteor showers are best seen when viewed from a site far from urban lights.

On the evening of Saturday January 5th at about 7 p.m. telescopes magnifying at least 20 times can show the four largest moons of Jupiter all arrayed to the west of the planet. At that time their apparent sequence from Jupiter’s limb is Europa, Io, Ganymede, and Callisto. Both Io and Europa are approximately the size of Earth’s moon while Callisto and Ganymede the solar system’s biggest satellite, are about 50% larger than our Moon. If you recently obtained a telescope you can hardly find a more appealing first sight than watching Jupiter and its retinue of moons. This evening provides a very pleasing view of the tableau, surely one of the finest sights seen with a small telescope.

If you look toward the southeast after 3 a.m. Sunday January 6th the Moon may be seen in the constellation Virgo between the first magnitude star Spica and Saturn. Saturn currently has a visual magnitude of 0.62 compared to 0.98 for the slightly less bright Spica, brightest star in Virgo at a distance from Earth of 262 light years.

Visible if the early morning sky about seven a.m. Thursday January 10th is clear, the Moon is located about 12 degrees of arc from Venus in brightening twilight. Venus then has a visual magnitude of -3.93.

From twilight until about 6 p.m. during the early evening of Saturday January 12th the thin waxing crescent Moon is about eight degrees to the right of Mars. At similar times the following evening the Moon will have moved to about eight degrees above the Red Planet in the west-southwestern sky.

During the night of Wednesday the16th the wide crescent Moon is four degrees northwest from Uranus, with the planet having visual magnitude 5.87.

The night of Sunday January 20th the Moon is near the Pleiades open star cluster, a wonderful sight in binoculars.

Crab Nebula Composite (X-ray and Optical)
A composite image of inner parts of the Crab Nebula showing X-ray (blue), and optical (red) images superimposed. The visual wavelength image was obtained with the Hubble Space Telescope and the X-ray image is from the Chandra Space Telescope.
Credit: NASA/HST/ASU/J. Hester et al. X-Ray: NASA/CXC/ASU/J. Hester et al.

On the evening of the 21st, the waxing gibbous Moon is near the Hyades open star cluster in Taurus and around 9 p.m. the Moon will be less than one degree of arc from Jupiter. This eye-catching conjunction is well worth noting on your calendar. For observers in South America and the southern Pacific the Moon will occult Jupiter, blocking views of the planet.

With a telescope Jupiter’s four Galilean moons may be seen arrayed on both sides of the planet at around 7 p.m. on the evening of Tuesday January 22. At that time Ganymede and Io are to the east of Jupiter and Europa and Callisto are on the west of the planet’s disk. Ganymede and Callisto are the larger and brighter members of each pair.

January 23 the bright Moon is between the sky locations of the supernova remnant Messier 1, known also as M1 and the Crab Nebula, in Taurus and the open star cluster M35 in Gemini.

Wednesday evening January 23 at seven p.m. the Moon is about six degrees of arc from the eighth magnitude Crab Nebula, which is located near the third magnitude star ZetaTauri representing one of the Bull’s horn tips. At that same time the Moon is five degrees from M35 in the constellation Gemini. Unlike M1 which requires a moonless night far from urban lights to glimpse with a telescope, M35 is visible with binoculars on any clear night. At seven p.m. the evening of Wednesday the 23rd, the Moon is also just two degrees directly south of the point on the ecliptic known as the summer solstice, the sky position of the Sun on the first day of our summer season.

Friday January 25th, the Moon is between Procyon, brightest star in the constellation Canis Minor and the twin stars of Gemini. Procyon is one of the brightest stars in the sky with a visual magnitude of 0.40. At a distance of 11.41 light years from the solar system, it is also one of the closest stars to us. Pollux, the more southerly of Gemini’s twin stars, has magnitude 1.15 and is 34 light years from us. Just four and a half degrees to the northwest is Castor, Pollux’s mythological twin. Castor is certainly not a physical twin since at a distance of 51.6 light years from Earth, Castor is nearly five times further from us than Pollux. Nevertheless, with a visual magnitude of 1.58 Castor is just slightly fainter than Pollux—and this apparent similarity combined with their proximity in the sky inspired the ancient notion of them being twins.

The evening of Saturday January 26 the Full “Wolf” Moon is just south of the beautiful open star cluster known as Messier 44 in the constellation of the Crab. M44 covers approximately four times the sky area of the full moon and may be seen with unaided eyes from locales that provide dark skies.

On January’s last evening at six p.m., all four of the Jovian moons discovered by Galileo will be visible to the east of Jupiter. Their order in apparent distance from Jupiter then will be Io, nearly at the edge of the planet’s disk, followed by Ganymede, Europa, and finally Callisto, which will be about four minutes of arc from the limb of the planet.

Sky Lore

This winter Jupiter graces the constellation Taurus, believed to be one of the first recognized star patterns in western sky mythology. The Bull, representing the vigor of emerging spring, marked the location of the Sun at the time of the Vernal Equinox during a period from approximately 4000 to 1700 B.C. Since then, the precessional wobble of Earth’s rotational axis has brought the Spring Equinox into the constellation Aries and then to its current location in Pisces. In classic Hellenic myths, stars of Taurus represented a handsome bull into whose form Zeus had transformed himself in order to entice affections of lovely Europa. In addition to the famous and easily seen open star clusters of the Pleiades and Hyades, Taurus provides us with two fine examples of objects representing opposite stages in stellar evolution. The variable proto-star designated T Tauri, located near the Hyades, is puffing out vast quantities of dust and gas as it settles down to eventually begin producing light and heat through the process of nuclear fusion. At the other end of the evolutionary spectrum, a fast spinning neutron star, produced by a long-ago supernova explosion of a massive star, illuminates the Crab Nebula located between horn tips of Taurus.