Something cool is happening this weekend: Venus and Jupiter will look really close in the sky, almost appearing to touch each other, even though they’re millions of miles apart. They’ll appear their very closest on Saturday, April 30, around 3 p.m. ET. This is known as a “conjunction,” and while the experts at EarthSky have been advocating for people to watch the planets appear since the phenomenon started last week, you’ll have your best shot Saturday. Here’s what you need to know.
What is a planetary conjunction?
A planetary conjunction is a very simple kind of illusion: That’s the name we use when two things in space (like asteroids, moons, stars, or planets) look like they’re close together when seen from Earth. They’re not close together up there, but it’s cool to see them look like they are.
There are systems in place to help astronomers pinpoint where objects appear in the sky. The celestial coordinate system of right ascension and declination, for instance, is aligned with the Earth’s tilt and fixed to standard points in the sky. Then there’s the ecliptic coordinate system, which is fixed to the solar system’s orientation within the galaxy. That one is measured in ecliptic latitude and longitude.
To be in conjunction with each other, two objects in space have to have the same right ascension or the same ecliptic longitude. But to see the conjunction, you don’t actually have to know what those are.
What’s going on with Venus and Jupiter?
We all know our solar system’s planets orbit the sun. Orbits are elliptical and inclined a bit in respect to other orbits. Every once in a while, two planets’ orbits will align so that they appear close to each other from Earth.
That’s what is happening right now with Venus and Jupiter. They’re both on their elliptical paths, heading toward each other more than usual—at least from the vantage point we have here on Earth, which sits between the two. Venus is closer to us, Mars is on the other side of us, and Jupiter comes after that.
Per EarthSky, the two planets will look closest in our sky on the mornings of April 30 and May 1. At conjunction, Venus will be just .2 egress south of Jupiter, which is less than the full diameter of the moon. Again, you don’t really need to know what all this means to enjoy the big moment; it’s just kind of cool.
How can you see the Venus-Jupiter conjunction?
Venus and Jupiter have been appearing to creep closer to one another for a few days and on May 1, they’ll look like they’re starting to separate, so feel free to keep an eye on them all the while to see them pass like two ships in the night.
You won’t need a telescope to see the planets on April 30 and May 1. If you’re in the Northern Hemisphere, look along the southeastern horizon at dawn, according to CNN. Just be sure it’s still dark enough that you see some stars. In the Southern Hemisphere, the conjunction will be visible above the eastern horizon.
They’re on a path to be more visible than some previous conjunctions because they won’t be as close to the sun as they have in the past. You’ll be looking for little pinpricks of light. Mars and Saturn are also joining the party and will align roughly north of Venus and Jupiter, but while four planets will technically be visible, the big draw is Venus and Jupiter’s conjunction, so if you’re having trouble, just focus on looking for the two very close pinpricks of light.