by William J. Bechaver
EARTH — This is the week when the moon passes amongst the planets, encountering each as is passes through our night sky. But, oddly, none of the lunar and planetary encounters this month will be particularly close ones. Instead, the moon will end up bookending the planets on successive nights.
The first pretty pairing is tonight, Thursday the 23 of March. Though not close enough to be considered a conjunction, it will be a beautiful sight to behold.
Go out anytime after sunset and look to the west. Brilliant Venus will attract your attention immediately. It shines so brightly in the evening twilight, it can’t be missed on a clear night, nor mistaken for anything other than what it is, the nearest and brightest planet in the sky. Below it, about five degrees lower, you will find the beautiful crescent moon.
Venus has climbed so high now, it remains in the sky nearly three hours after sunset, so there is plenty of opportunity to view it on any given night. On Thursday, the moon will set only twenty minutes before Venus.
The following evening, Friday March 24, Venus will hold a little higher position above the horizon. But now the moon will have catapulted its way much higher, resting about six degrees above the brilliant planet. Neither apparition is particularly close together, but the brilliance of the two objects involved make it a stunning sight to witness, just by stepping out and looking west. Little effort, and a major reward.
The lunar Mars encounter will be similar next week. On Monday March 27, the moon will be about four degrees west of Mars. Not a near encounter, and really not much to look at. Mars is growing so faint right now, the distance and the faintness of the planet, the pairing won’t be noticable at all, if you aren’t looking for it. Then, on Tuesday evening, the moon will be about eight degrees east of Mars. The only advantage of viewing the moon on these two nights will be the opportunity to spot faint Mars, amongst the stars of Taurus.
The more spectacular viewing for Monday the 27 will come much earlier in the evening. But it will be a challenge to see. You will need a pretty low western horizon, and extremely clear skies that evening if you want to see Jupiter as it is joined by Mercury.
Jupiter is just exiting our evening sky, sinking lower every night, on its way around the far side of the sun. Mercury is just emerging in our evening sky following its passage around the far side of its orbit. But viewed from Earth, the two will come together on Monday evening, and be viewable just after sunset.
Jupiter is the largest planet in the solar system. But as it makes its way around the far side of the sun, it is being viewed from Earth at a great distance. Mercury is the smallest of the planets. Also passing on the far side of the sun, but much nearer Earth than is Jupiter. On Monday evening, the two will appear side by side in the twilight glow, seen only briefly before the pair set together before the sky even has a chance to grow dark.
About a half an hour after the sun has set, go out and look in the evening glow in the west. It might help to use a pair of binoculars, and scan low along the horizon. If you find fading Jupiter, to the right you should be able to discern faint Mercury. They are only a couple degrees apart. But finding the pair will take luck and diligence. Greater effort, for greater reward, if you are able to find the pair before they set, only an hour after sunset.
So, as the moon passes amongst the planets, there are no extremely close encounters to be viewed this week. And the closest encounter of all, with Jupiter and Mercury, will take some skill to view in the short time before the pairing is gone.
With our dark skies here, they only need to be clear, so keep your eyes on the skies from sunset to sunrise.
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Astronomical times and distances of naked-eye objects for this weekend:
Sun Set = 7:15 p.m.
7 minutes later than last week
92.706 million miles from Earth
182,250 miles further than last week
1,303,361 miles further than its nearest in January
Mercury Set = 7:56 p.m.
43 minutes later than last week
41 minutes after the Sun
117.649 million miles from Earth
7,242,902 miles nearer than last week
9.559 million miles nearer than its furthest in March
Jupiter Set = 8:14 p.m.
19 minutes earlier than last week
59 minutes after the Sun
550.357 million miles from Earth
2,877,104 miles further than last week
182.942 million miles further than its nearest in September
Venus Set = 10:12 p.m.
15 minutes later than last week
2 hours 57 minutes after the Sun
114.263 million miles from Earth
3,940,758 miles nearer than last week
45.343 million miles nearer than its furthest in October
Moon Set = 12:02 a.m.
67 minutes later than last night
240,910 miles from Earth
3,555 miles further than last night
15,469 miles further than last week
Nearest is 221,557 miles
Furthest is 252,566 miles
Mars Set = 2:16 a.m.
13 minutes earlier than last week
129 662 million miles from Earth
6,499,373 miles further than last week
78.937 million miles further than its nearest in December
Saturn Rise = 5:37 a.m.
25 minutes earlier than last week
76 minutes before the Sun
988.179 million miles from Earth
5,138,891 miles nearer than last week
16.699 million miles nearer than its furthest in February
Sun Rise = 6:53 a.m.
11 minutes earlier than last week
92.718 million miles from Earth
12,568 miles further than last night
168,715 miles further than last week
1.315 million miles further than its nearest in January
First Quarter Moon occurs on Tuesday, March 28, at 8:32 p.m. We’ve gained 17 minutes of daylight since last week, or 68 minutes since last month, and a full two hours 49 minutes since the December Solstice. Our nearest planetary neighbor currently is Venus. No planet in the dark sky for three hours 21 minutes. This is the duration between Mars Set and Saturn Rise in the morning. No planets are visible during this period.
Note: Times are local Mountain Time. Actual “sundown” is about a dozen minutes earlier than calculated “sunset”. Along the front range, differing times vary depending on your distance from the mountains.
William J. Bechaver is the director of SPACE • Spanish Peaks Amateur Cosmos Enthusiasts, the premier Astronomical Society for Southern Colorado and Northern New Mexico.
