Like resurrected gods, Mercury and Venus passed closest to the fiery glare of the sun earlier this month and disappeared from view for a time. Now they’ve returned but on opposite sides of the sun – Mercury in the evening and Venus in the morning.
Venus lingered for months in the dusky dusk until Jan. 11 when it passed between the sun and Earth and disappeared in the solar glare. Now she’s west of the sun, rising at dawn and visible with the naked eye about 40 minutes before sunrise.
Mercury has also stayed “close” to the sun and hidden from northern hemisphere sky watchers’s eyes during the first half of January. Now it’s crawling up the southwestern evening sky and will gradually become easier to see in the next week. While a feeble replacement for brilliant Venus, the solar system’s elusive, innermost planet is a rarer sight by far.
I’ve prepared simple maps for you to find both of these wanderers. You’ll need a clear horizon to the southeast to spy Venus and the same to the southwest for Mercury. You’ll find Venus much easier to spot because it’s so much brighter than Mercury and somewhat higher too.
If you’ve been following the planet over the last month, you’ll notice that the crescent is reversed from its evening appearance, with horns pointing up to the right instead of left. Tomorrow morning the crescent measures 59 arc seconds across or nearly one arc minute (60 arc seconds), equal to 1/30 the diameter of the full moon. 7-10x binoculars will easily show the delicate Venusian crescent.
Don’t expect to see Mercury’s humpbacked gibbous phase in the old opera glass. The munchkin planet spans only 3,032 miles across (2.5 times smaller than Venus) and is currently on the far side of its orbit 4.6 times farther from Earth than Venus. With a disk just 5.5 arc seconds across, Mercury’s phase will require a telescope magnifying around 100x to see clearly.
Now all you’ve got to do is resurrect yourself from the couch and go out for a look.