Mercury is notoriously difficult to spot with the naked eye, thanks to its proximity to the sun. Most of the time, you get only a few minutes to see it before the sun comes up over the horizon, obscuring your view with daylight. But if you want the best view of the smallest planet in our solar system, the first two weeks of September are your chance.
Through Sept. 14, Mercury is far enough away from the sun to be seen while it's still dark outside. Your best bet is to catch it between now and Sept. 10.
What's the best time to see Mercury?
On Sept. 5, Mercury rose over the horizon at around 5:50 local time in the eastern skies. By 6, it was plainly visible and remained that way for around 45 minutes. After that, the sunrise impeded the view. Each day after Sept. 5, Mercury will rise a little bit later in the morning, until it starts to appear only after dawn has begun.
By the morning of Sept. 14, Mercury will rise around 6:15 local time around most of the US and will have just barely cleared the horizon before the sky starts to brighten. So, if you haven't checked it out by then, you'll have to wait for the next time Mercury makes its way that far away from the sun. Fortunately, you don't have to wait long, since Mercury's orbit is only 88 days.
Will I need a telescope or binoculars to see Mercury?
No, and that's why this event is special. Mercury is usually so close to the sun that it's difficult to see with the bright sunlight. During this window, however, Mercury is far enough away to be visible in the night sky, with no light from the sun to hinder you.
But it's the smallest planet in our solar system, so binoculars won't hurt.
How do I find Mercury?
Mercury will rise in the eastern sky no matter where you are in the continental US. Time and Date as well as Stellarium have free night-sky web tools that let you search for the planet to see where in the sky it'll be. For mobile help, Star Walk 2 on iOS and Android works quite well to help you find various celestial bodies.
While you're looking for Mercury, keep on the lookout for T Coronae Borealis as well. The white dwarf star is set to nova any time now and it'll add a new — albeit temporary — star in the sky.
The last days of August featured the moon and Mercury cozying up together in the night sky. Mercury is also part of the ongoing planet parade where you can see six planets in the night sky.