My first Magazine Sky & Telescope - 01.2019 | Page 49

Venus appears to plummet past Jupiter, from Libra down through Scorpius. Around January 12th, Venus passes by Scorpius’s head and forms the peak of a tall triangle with Jupiter and Antares as the base corners of the triangle. Then, around January 19th, Venus is 3¾° above Jupiter, with Antares at just about the same altitude as Jupiter, forming a squat right triangle.  Venus and Jupiter are a minimum of 2½° apart on January 22nd. Tele- scopes then show Venus’s dazzlingly bright form as 21″ across and about 60% lit. Jupiter’s much duller but fully lit disk is 33″ wide.  On January 26th viewers at mid- northern latitudes can see Venus, Jupiter, and Antares form a horizontal line, with a little more than 4° separat- ing the two planets and twice again that distance between Jupiter and the star. By January 31st, the gap between Venus and Jupiter has widened to 9½°, with Jupiter to the upper right of Venus, ris- ing almost half an hour before Venus. DAWN Mercury glimmers around 5½° high in the southeast a mere 30 minutes before December solstice Uranus Venus March equinox Jupiter Neptune Saturn sunrise on the opening days of 2019. It then shines as the bottom-left planet in a long diagonal line equally spaced with Venus and Jupiter. Mercury brightens, from magnitude –0.4 to –0.7, in the first half of January but is simply too low in strong twilight glow to be seen after the 3rd or 4th. Mercury reaches superior conjunction with the Sun on the night of January 29–30. Saturn is in conjunction with the Sun on January 2nd so isn’t visible Moon Jan 29 Moon Jan 30 Jupiter Antares Venus SCORPIUS Moon Feb 1 Saturn Looking Southeast Mercury The curved arrows show each planet’s movement during January. The outer planets don’t change position enough in a month to notice at this scale. 45 minutes before sunrise Moon Feb 2 Sun ORBITS OF THE PLANETS Dawn, Jan 29 – Feb 2 S A G I T TA R I U S Sept. equinox June solstice q These scenes are drawn for near the middle of North America (latitude 40° north, longitude 90° west); European observers should move each Moon symbol a quarter of the way toward the one for the previous date. In the Far East, move the Moon halfway. The blue 10° scale bar is about the width of your i st at arm’s length. For clarity, the Moon is shown three times its actual apparent size. Moon Jan 31 Mars Earth C a t ’s Eyes Looking South-Southeast when it passes less than 2° from Mer- cury on January 13th. The ringed planet emerges into visibility in morning twilight around the third week of the month. The +0.6-magnitude world has increased its lead on the Sun to more than 1½ hours by month’s end. EARTH, SUN, AND MOON Earth comes to perihelion, a minimum of 0.98 a.u. (specifically, 147,099,761 km) from the Sun, at 5 h UT on January 3rd. The Sun is partially eclipsed for observers in parts of eastern Asia, Micronesia, and the Aleutian Islands on January 5–6 (see page 50 for details). The Moon is totally eclipsed on the night of January 20–21; for full infor- mation, see page 18. The waning lunar crescent is 5° upper right of Venus on January 1st and slightly farther, around 7°, lower left the next morning. The slim lunar sliver is 3° to 4° left of Jupi- ter on January 3rd and around 3° above a low Mercury a mere half-hour before sunrise on January 4th. The thick wax- ing crescent Moon is some 5° lower left of Mars on January 12th. The waning Moon crescent is 6° to 7° upper right of Jupiter on January 30th and the next morning between Jupiter and Venus, around 2° to the right of Venus. ¢ Contributing Editor FRED SCHAAF was six years old when he saw his irst lunar eclipse (one that at the time was oficially listed as total) in August 1961. sk yandtele scope.com • JA N UA RY 2 019 47