Skywatch: Moon and Venus to pair up

Much of North America will be favored with the best view of this moon-Venus pairing. Across the northern and central U.S. and southeast Canada, the minimum distance separating the two will be no more than one-degree (the apparent width of the moon is roughly one-half degree).  Keep in mind that this display will be an illusion of perspective: the moon will be only about 233,000 miles (375,000 kilometers) from Earth, while Venus is nearly 347 times farther away, at 80.9 million miles (130 million kilometers). 

And because the moon is so much closer to us than Venus, it will be possible to see it change its position relative to Venus over a span of just a few hours.  From New York City, for instance, at sunset, the moon will appear to be directly to the right of Venus.  But three hours later, the moon will have moved to a point above and to the right while the gap between the two will have been halved.

For most locations, the moment of closest approach between the moon and Venus will come after sunset.  The exceptions will be over the Pacific Northwest States and western Canada, where the closest approach occurs before sunset; for these regions, the moon and Venus will be slowly separating during the early evening hours.

In the table below, I have calculated the viewing circumstances for 18 selected U.S. and Canadian cities.  The time of local sunset is given, as well as the time when Venus and the moon will appear closest together (keep in mind the moon moves in an easterly direction against the star background at its own apparent width per hour).  Notice that for eastern locations nearly three hours will elapse between sunset and closest approach, while for some far-western locations these events will nearly coincide.  A "D" indicates that closest approach comes before sunset.  The minimum separation distance (Sep.) and the moon's altitude (Alt.) above the horizon are provided as well.   

While those using binoculars or a small telescope will enjoy the almost three-dimensional aspect of the moon, Venus will be rather disappointing, appearing as brilliant blob of light, for right now, Venus appears as a tiny, featureless gibbous disk.  That will change in the coming weeks, however, as Venus approaches Earth and the angle it makes between us and the sun allows it to evolve into a "half-moon" phase in early June . . . and a lovely crescent phase of its own during July.

City	Time Zone	sunset	Closest	Sep.    Alt.
Montreal	EDT	8:21 p.m.	10:56 p.m.	0.9°     9°
Boston	EDT	8:01 p.m.	10:56 p.m.	0.9°     6°
New York	EDT	8:09 p.m.	11:01 p.m.	0.9°     6°
Washington	EDT	8:16 p.m.	11:06 p.m.	0.9°     7°
Atlanta	EDT	8:33 p.m.	11:15 p.m.	1.0°     8°
Miami	EDT	8:01 p.m.	11:21 p.m.	1.1°   <1°
New Orleans	CDT	7:48 p.m.	10:26 p.m.	1.1°     9°
Kansas City	CDT	8:25 p.m.	10:15 p.m.	1.0°    17°
Chicago	CDT	8:06 p.m.	10:06 p.m.	1.0°    15°
Austin	CDT	8:19 p.m.	10:28 p.m.	1.1°    15°
Winnipeg	CDT	9:12 p.m.	9:55 p.m.	1.0°    26°
Denver	MDT	8:10 p.m.	9:15 p.m.	1.1°    26°
Helena	MDT	8:59 p.m.	9:00 p.m.	1.1°    34°
Edmonton	MDT	9:33 p.m.	8:41 p.m. D	1.0°    38°
Tucson	MST	7:16 p.m.	8:28 p.m.	1.2°    26°
San Francisco	PDT	8:15 p.m.	8:16 p.m.	1.2°    39°
Los Angeles	PDT	7:49 p.m.	8:25 p.m.	1.2°    33°
Seattle	PDT	8:44 p.m.	7:50 p.m. D	1.1°    43°

MORE FROM SPACE

Space Section Front

Looking for alien Earths? Here they come   Cosmic Log: Another 'UFO' from Russia Brightest gamma-ray flare in universe spotted Mars moons pictured together for first time ‘Gem’ of a meteor shower reaching climax Wheel trouble may doom stuck Mars rover Russia admits missile caused UFO lights Cosmic Log: Planets on the Web Hunt for new worlds goes into overdrive Top 11 planet-hunting telescopes   Space Section Front   Add Space headlines to your news reader: