Jupiter Is Coming Its Closest To Earth In Decades
The gas giant Jupiter is coming the closest it has come to Earth in 59 years this Monday and will be particularly visible because it coincides with another event called opposition.
When in opposition, a planet is on the opposite side of Earth from the sun, so you could draw a straight line from the sun to Earth to Jupiter, all in alignment. Jupiter's opposition happens every 13 months. Looking from the Earth, when the sun sets in the west, Jupiter will rise in the east, directly opposite. During opposition, planets appear at their biggest and brightest.
Separately, Jupiter is coming closer to Earth than it has since 1963. Because of Earth's and Jupiter's differing orbits around the sun, they don't pass each other at the same distance each time. When it's closest on Monday, Jupiter will be about 367 million miles from Earth, according to NASA. At its farthest, it's 600 million miles away.
The result of both is that the views may be somewhat better than normal.
"Jupiter is so bright and brilliant that a really nice thing about it is even in a city, in the middle of a bright city, you can see it," says Alphonse Sterling, a NASA astrophysicist at the Marshall Space Flight Center in Huntsville, Alabama. "So I would say that it's a good thing to take advantage of and to look at no matter where you're at."
He mentions that Jupiter is always easily visible in the night sky as long as it's not near the sun and that it might be hard for a casual observer to notice any difference in size.
Sterling says he was also able to see the largest moons of Jupiter a few days ago with just a pair of 7x50 binoculars (7 times magnification with a 50 mm objective lens).
Io, Europa, Ganymede and Callisto are the four moons referred to as Jupiter's Galilean satellites. The term comes from Galileo Galilei, who discovered them more than 400 years ago.
If you don't have a telescope, you'll need a way to hold binoculars very steady to get a good view. Sterling says he used a ledge.
"I could definitely see the moons, you know, off to the side of Jupiter looking like little stars," he says. "So that's a fun thing that can be done. And that's certainly easier now than it would be if Jupiter's at its furthest."
The Galilean satellites are among Jupiter's 53 named moons, though scientists have found 79 in total.
A month ago, NASA released new images of Jupiter and its moons taken by the James Webb Space Telescope. Additionally, NASA's Juno spacecraft has been providing excellent images since it began orbiting Jupiter six years ago.
The next time Jupiter will come this close will be in 2129.