Astro Bob: Venus returns in a wonderful dawn conjunctions with the Sliver Moon
"Astro" Bob King is a freelance writer for the News Tribune. Read more of his work at astrobob.areavoices.com.
On Friday morning, June 19 a slender lunar crescent will pair up with Venus low in the northeastern sky at dawn. Venus has been lost in the solar glare in recent weeks after its June 3rd conjunction with the Sun. It returns this week in a big and beautiful way with the moon. But you’ll have to be an early bird as the pair won’t clear the northeastern horizon until about 45 minutes to an hour before sunrise.
But what a sight they’ll make! Skywatchers across much of the U.S. will see them rise together separated by only about 1° while those on the East Coast will get a tighter view yet, with just one moon diameter between them. There’s an even more amazing aspect to the conjunction. If you own binoculars you can see two crescents. The lunar crescent will be wafer-thin and only 3.5 percent illuminated while Venus will appear slightly thicker at 8 percent. Even a pair of 7x35s or 10x50s will show this amazing side-by-side slivery sight.
The moon stands about 4° high and Venus 5° in a bright, twilight sky when they’re best visible. To make sure both aren’t hidden by trees or buildings seek a site with a view as far down to the northeastern horizon as possible. Then set your alarm for around for an hour or so before sunrise and arrive at your location with binoculars and camera. Use this sunrise calculator to find the local time of sunrise and this moonrise calculator to know when the moon comes up. At my house sunup occurs at 5:14 a.m. so I plan to be ready to go around 4:15 a.m. Whoa, that’s early!
In the far northeastern U.S. and eastern Canada the moon will occult (cover up) Venus before moonrise. Skywatchers there will be able to see the planet reappear at the moon’s dark edge after occultation, a dramatic sight! Make sure you’ve got a clear horizon since the moon will only be 1-2° high. As the moon rises higher Venus will slowly separate to the west.
Farther east — including Nova Scotia, Newfoundland, Greenland, northwestern Europe and northern Asia — skywatchers will see the moon occult the planet either shortly before sunrise (Canada) or in the daytime sky (Europe and Asia). The moon’s bright crescent edge will cover Venus first and the planet will reappear along the dark edge. Click here for a list of selected cities and times when Venus disappears and then reappears from behind the moon during the event. Times shown are UT or Universal Time. Subtract 3 hours to convert to Atlantic Time; 4 hours for Eastern and 5 for Central.
No matter where you see this pairing of two crescents I guarantee the sight will inspire your day.