The sky is gearing up for a very cool event: On June 30 and July 1, Venus and Jupiter will pass extremely close together in the sky, less than a third of a degree apart!
That’s close. The full Moon is a half degree across, so this will be very pretty. And it plays out over several days, so you’ll have plenty of chances to see it.
The planets orbit the Sun more or less in the same plane. We’re in that plane, too, so we see the solar system from the inside, and edge-on. That means that as the planets move around the Sun we see them moving along the same line in the sky, which we call the ecliptic.
In reality the planets’ orbits are all tilted slightly with respect to one another, so they don’t follow the exact same line. This means that, from Earth, we see them pass by each other in the sky, sometimes closer than other times. Usually they miss each other by a few degrees—and remember, this is just a perspective effect. In reality the planets are hundreds of millions of kilometers apart.
Venus orbits the Sun closer than Earth does, and Jupiter well outside. Right now, Venus is “rounding the corner” of its orbit, on the near side of the Sun and starting to overtake us. Jupiter is headed for superior conjunction, when it’s on the other side of the Sun from us. All these motions combined means Venus and Jupiter are approaching each other in the sky, getting closer every night.
If you go outside just after sunset (even before the sky is totally dark) and look to the west, you won’t miss them; Venus and Jupiter are the third and fourth brightest natural objects in the sky. It’s been pretty rainy where I am, but the other night we had clear skies and I saw them about 10° apart. They’re already making a striking pair.
They get closest together around 03:00 UTC on July 1 (which is in the evening in the U.S. on June 30). At that point they’ll be about 17 arcminutes apart (there are 60 arcminutes to a degree, so the Moon is 30 arcminutes in size). Through a telescope they’ll be amazing. They should both fit easily under low power. Jupiter’s disk will show stripes, the moons will be visible, and Venus will shine in a waning crescent phase.
This is the closest the pair have been for a while … but just wait until next year. They’ll get an incredible 4 arcminutes apart on Aug. 27! That’s during the day here in the U.S., but should be visible with binoculars or a telescope. So think of this month as a warmup.
In the meantime, get out and watch! It’s fun to go out every night and see them get closer. If the weather holds up, you can bet I’ll be outside, and looking through my own ‘scope, too.
For more info, and more events like this, check out the article on Universe Today.