JUPITER’S MOONS JANUARY

Using a small scope you’ll be able to spot Jupiter’s biggest moons. Their positions change dramatically during the month, as shown on the diagram. The line by each date on the left represents 00:00 UT.

Mercury

Best time to see: 1 January, 30 minutes before sunrise Altitude: 1.5º (very low) Location: Sagittarius Direction: Southeast Mercury starts January as a morning object but is so close to the Sun it’s difficult to see. On 1 January it’s at mag. –0.4, appearing about an hour before sunrise above the southeast horizon. Superior conjunction occurs on 30 January.

Mars

Best time to see: 1 January, 18:00 UT Altitude: 36º Location: Pisces Direction: South Mars is an evening object in Pisces. Through a telescope, the mag. +0.5 planet appears just 7 arcseconds across on 1 January, located southeast of the Circlet asterism. For the rest of the month Mars races east, remaining in Pisces as it goes. By the end of the month, Mars is within the narrowing wedge of stars representing the cord tying the fishes of Pisces together, slightly east of mag. +4.3 Epsilon (¡) Piscium. The planet will dim to mag. +0.9 by 31 January and telescopically will appear just 6 arcseconds across, its disc showing an 89%-lit phase.

Jupiter

Best time to see: 31 January, from 06:00 UT Altitude: 7.5º (low) Location: Ophiuchus Direction: Southeast Jupiter rises a couple of hours before the Sun at the start of January, shining at mag. –1.6 against the stars representing Ophiuchus’s legs. Mag. –4.4 Venus, Jupiter and mag. –0.4 Mercury appear in a line on New Year’s Day, with a 21%-lit waning crescent Moon 7° west of Venus. On 2 January, the 13%-lit waning crescent Moon sits between Venus and Jupiter. On 3 January a now 6%-lit Moon lies 2.3° north of Jupiter, an impressively close pairing. By the end of January, Venus appears to the eastnortheast of Jupiter with both planets rejoined by the waning crescent Moon. On 30 January the 25%-lit waning Moon sits west of Jupiter. However, this gets better the following morning with a 17%-lit waning crescent Moon located between Venus and Jupiter – quite a spectacle for early risers.

Saturn

Best time to see: 31 January, 1 hour before sunrise Altitude: 1.6º (very low) Location: Sagittarius Direction: Southeast Saturn’s too close to the Sun to be seen properly this month. It may be glimpsed with the naked eye low in the southeast towards the end of January, joining a line-up with mag. –4.1 Venus and mag –1.7 Jupiter.

Uranus

Best time to see: 1 January, 19:10 UT Altitude: 47º Location: Pisces Direction: South Uranus is a well-placed evening object at the start of January, visible around 18:00 UT on New Year’s Day, close to its highest point in the sky due south. By the end of January, it will have drifted west. In theory mag. +5.8 Uranus should just be visible to the naked eye from a dark-sky location. It’s currently located in Pisces.

Neptune

Best time to see: 1 January, 18:20 UT Altitude: 25.5º Location: Aquarius Direction: West of south Neptune is in the southwest as darkness falls at the start of the month, then creeps westward. It’s low in the west-southwest as the sky darkens at the end of January, shining at mag. +7.9 all month. You’ll need at least binoculars to see it against the eastern stars of Aquarius.