My first Magazine Sky & Telescope - 03.2019

MARCH 2019 OBSERVING Sun, Moon & Planets by Fred Schaaf To fi nd out what’s visible in the sky from your location, go to skypub.com/ almanac. Three Worlds at Dawn During the night’s second half, three planets come into view. fter the ﬁ rst week of March, Mercury disappears into the Sun’s afterglow. That yet again leaves dim- ming Mars as the only bright planet visible in the evening sky — but at least it beautifully drifts up near the Pleiades by month’s end. A few hours after the late-evening setting of Mars, Jupiter rises. It’s followed about two hours later by Saturn. Still later, Venus rises, near dawn’s ﬁ rst light. By late March, Mercury, having passed into the morning sky, is creeping into view below Venus around the time Jupiter is highest in the south. A DUSK ONLY Mercury was at greatest eastern elonga- tion in the evening sky on February 27th. It starts March still setting about 1½ hours after the Sun and shining at magnitude +0.1 with its 8″-wide disk about 35% lit. But this innermost DUSK AND EVENING Mars is almost halfway up the south- west sky an hour after sunset this month and doesn’t set itself until near midnight daylight-saving time. Unfortunately, the Red Planet dims even further in March — from magni- tude 1.2 to 1.4 — with its disk decreas- ing from 5.3″ to 4.6″ wide. At least Mars passes through a lovely section of the zodiac in March, appearing some 3° below the Pleiades at month’s end. PRE-DAWN AND DAWN Jupiter rises around 2 a.m. standard time on March 1st but not too long after 1 a.m. daylight-saving time on March 31st. Its magnitude brightens from –2.0 to almost –2.3 this month, its equatorial diameter increasing from 36″ to almost 40″. Jupiter passes through western quadrature (90° west of the Sun) in March, improving views of some of the phenomena of its Galilean satellites (see page 51). The best time to get a sharp view of Jupiter’s many Dawn, March 1–3 Dusk, March 1 Dusk, March 11–13 45 minutes before sunrise 45 minutes after sunset PISCES planet is fading rapidly as its phase thins and by about March 6th is fainter than magnitude 2.0 and no longer read- ily detectable. Mercury reaches inferior conjunction with the Sun on March 15th — just two inferior conjunctions before the one in which it will tran- sit across the face of the Sun for the last time in 13 years (the transit this November 11th will be visible in the Americas, Europe, and Africa). Neptune is at conjunction with the Sun on March 7th and not viewable this month. Uranus can still be observed when the last of evening twilight fades, though it appears lower and lower at that time with each passing week in March (see the September 2018 issue, pages 48–49, for a ﬁ nder chart). 1 hour after sunset Moon Mar 13 PEGASUS Moon Mar 1 Great Square Saturn β Cap 10° Moon Mar 2 Venus Mercury Moon Mar 3 Aldebaran Moon Mar 12 Pleiades TA U R U S Moon Mar 11 Mars Looking West 46 M A RCH 2 019 • SK Y & TELESCOPE Looking Southeast Looking West-Southwest, halfway up

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