OBSERVING January 2018 1 MORNING: The New Year kicks off with Mercury at greatest western elongation. Look toward the southeast before sunrise and you might catch a glimpse of this tiny world. EVENING: The first full Moon of the year (for viewers in North America) coincides with its closest perigee of the year. 3-4 NIGHT: The short-lived Quadrantid meteors peak for North America, but the full Moon makes viewing any of this shower's meteors a challenge. 4-5 NIGHT: The Moon slides past Regulus in Leo and will occult the 1st-magnitude star for viewers in parts of northern Canada and Alaska. 6 DAWN: Find Libra, and you will see Mars and Jupiter shining less than 1/3° from each other. Alpha (α) Librae sparkles 2° to the upper right of the pair. 11 DAWN: Jupiter and Mars are joined by the waning crescent Moon. Look about 20° lower left of the trio to find Antares. 12 EVENING: Algol shines at minimum brightness for roughly two hours centered at 9:45 p.m. EST (6:45 p.m. PST); see page 50. 13 DAWN: Tiny yet shiny Mercury is joined by majestic Saturn as they rise less than ½° apart in the southeast just before sunrise. The Moon hangs some 6° upper right of Saturn. 15 DAWN: The thinnest sliver of a waning crescent Moon, having just been at its most distant apogee for the year during the night, joins Mercury and Saturn to form a delightful compact triangle. 27 MORNING: As the Moon returns to full, it occults Aldebaran in northwestern North America; see p. 50. 31 ALL NIGHT: The asteroid Ceres arrives at opposition and is expected to shine at magnitude 6.9. Bring binos to spot this dwarf planet. MORNING: The last day of January heralds the second full Moon of the month. Much of western North America will witness the first total lunar eclipse in over 2 years (see p. 48). p NASA's MESSENGER spacecraft arrived at Mercury in 2011 and proceeded to study the tiny planet using multiple scientific instruments. NASA / JOHNS HOPKINS UNIVERSITY APPLIED PHYSICS LABORATORY / CARNEGIE INSTITUTION OF WASHINGTON sk yandtelescope.com * JA N UA RY 2 018 41http://www.skyandtelescope.com/