Bad Astronomy

Venus and Mercury kissing in the west

Over the next few days, get yourself outside at sunset and look west. As the sky darkens, Venus will be obvious and easy to spot above the horizon, a brilliant beacon hovering in the sky. But for a few days, the elusive Mercury will also be popping in for a visit!

Mercury orbits much closer to the Sun than Earth does, and so from our vantage point never seems to stray far from our nearest star. It’s always lurking in the twilight, and most people can go their whole lives without seeing it. It’s rumored (though by no means established fact) that Copernicus himself never saw Mercury. But this week will provide you with an excellent chance to spot it. It will stay near Venus for several days, and with no other bright stars nearby it will be fairly easy to pick out.

Both Mercury and Venus move faster in their orbits than Earth does, so if you go out every night you’ll see them change positions slightly in the sky. From our perspective, Venus is on the far side of the Sun, and Mercury to the side. After about April 10, Mercury will start to fade rapidly, so get out there and take a look! More info and diagrams to help you spot the planetary duo can be found at the Sky and Telescope website.

And I’ll add that if you have a digital camera, try to get some photos! The planets are bright enough to show up in images easily, and if you get an interesting foreground object (a tree, a bridge, etc.) you can get some very nice shots.