Venus shines at its brightest before dawn
The “morning star” dazzles as it climbs high and shines brightly during morning twilight in February and March.
If you head outside any clear February morning, your eyes will be drawn to a blazing light hanging in the southeastern sky. At first you might think it’s a plane coming in for a landing. But this is no object flying low in our atmosphere — it’s the brightest planet in the solar system. Venus appears especially prominent in February because it shines brightest and appears highest in the morning sky.
Venus shines at magnitude –4.9 — the brightest it ever gets — from February 8 to 16. (It officially reaches the point of “greatest brilliancy” on the morning of the 15th, but the difference is imperceptible.) This makes it nearly 10 times brighter than the sky’s second-brightest point of light, the planet Jupiter, which dominates the sky from dusk until about the time Venus rises. Venus fades slowly thereafter, dipping only to magnitude –4.8 by the end of February and a few tenths more during March.
Venus also appears highest in the morning sky from mid-northern latitudes during the second half of February. It rises about 2½ hours before the Sun throughout this period and climbs approximately 15° above the southeastern horizon an hour before sunrise. “Venus now appears higher and brighter in the morning sky than at any time since 2012,” says Astronomy magazine Senior Editor Michael E. Bakich. “You don’t want to miss this opportunity because it won’t be as high again until it returns to the evening sky in early 2015.”
The inner planet moves farther from the Sun in March, but it actually drops lower in the sky. You can blame solar system geometry for this apparent contradiction. The ecliptic — the Sun’s apparent path across the sky that the planets follow closely — makes a steeper angle to the eastern horizon before dawn in February than it does in March. So, even though Venus’ elongation from our star grows during March’s first three weeks, that increase translates more into distance along the horizon and less into altitude. At greatest elongation March 22, Venus lies 47° west of the Sun but rises only two hours before our star and appears 10° high an hour before sunrise. It is still a beautiful sight, just not quite as good as in the latter half of February.
Although Venus looks impressive by itself, a nearby crescent Moon can turn the morning vista stunning. The best conjunctions in February occur on the 24th (when the Moon lies to the planet’s upper right) and the 25th (with our satellite to Venus’ lower left). In March, the best view comes on the 27th, when the waning crescent Moon appears to Venus’ upper left.
The morning twilight sky in mid-March holds another planet worth viewing: innermost Mercury. This Sun-hugger reaches greatest elongation from the Sun on the 14th, just eight days before Venus does, when it lies 28° west of our star. It then appears 5° high in the east-northeast 30 minutes before sunrise. Mercury then shines at magnitude 0.1, some 60 times fainter than Venus but still bright enough to see through binoculars against the twilight glow.
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