Astro Bob: Shy Mercury joins Venus and the moon at dawn
Up early? Elusive Mercury beckons at dawn, and tomorrow it's joined by Venus and a razor-thin crescent moon.
Even though we lost an hour of darkness at dawn when daylight saving time ended earlier this month, the sun stills rises on the late side. In the northern U.S. it crests the horizon after 7 a.m. which makes it easier to get up to see what's shaking in the pre-dawn sky.
This Wednesday I set the alarm for 5:40 a.m. for a look at the ever-elusive planet Mercury. There are only a few times a year it's easy to see, and this is one of them. Because it's close to the sun and relatively far from the Earth, the planet never strays far from the solar glare. "Easy" for Mercury means you'll still need a fairly unobstructed horizon to see it. The planet's located in Virgo a little more than one outstretched fist below brilliant Venus in the southeastern sky.
I have a spot not far from my house with a good view in that direction. When I arrived I was amazed at how bright and obvious Mercury appeared. Couldn't miss it. I took in the sight and then returned home to observe the thick crescent moon (also on the scene) and Venus in the telescope. Energized by my planetary encounter and the growing light I shoveled the driveway from the previous night's 6-inch snowfall. Venus slowly diminished to a spark of light as the rosy glow of twilight proceeded to sunrise. By then I was getting hungry, so I had breakfast and read the paper. So began the day.
Starting the day in nature is never a bad way to go. Try it yourself tomorrow morning when the very thin crescent moon, less than two days before new, floats between Venus and Mercury in the southeastern sky. If you need help finding the planet, Venus and the moon are at your service. Together these three luminaries will make your heart happy. The lunar crescent will shine just 5° above Mercury, making it possible to see both in the same binocular field of view. Binoculars will also enhance the beauty and three-dimensional appearance of the semi-dark part of the moon illuminated by sunlight reflected from the Earth.
Click here to find your local sunrise time and then subtract about 75 minutes from that for the ideal time to see the trio.
If you use a telescope you'll see that both Mercury and Venus look like tiny waxing gibbous moons. Venus stays with us through the end of the year, but Mercury, the innermost and fastest-moving planet, will only be around for another week or so before it heads back into the sun's waiting arms.
My forecast calls for clear skies Friday morning, and I'll definitely be returning for another look. Won't you join me?
"Astro" Bob King is a freelance writer for the Duluth News Tribune. Read more of his work at duluthnewstribune.com/astrobob .