Jupiter will make its closest approach to Earth in 59 years on Monday, September 26, offering a surprise for sky watchers that evening.
Additionally, Jupiter will be in opposition, meaning it will rise in the eastern sky as the Sun sets in the west and make the largest planet in our Solar System particularly visible in the evening sky.
“Outside the moon, it should be one of (if not the) brightest objects in the night sky,” said Adam Kobelski, a research astrophysicist at NASA Marshall Space Flight Center.
Earth and Jupiter follow elliptical rather than circular orbits, and the distance at which they cross varies over time. On Monday, Jupiter will be within 367 million miles of Earth, compared to the 600 million miles that separate the two worlds when Jupiter is at the furthest point in its orbit from Earth.
Although Jupiter comes into opposition once every 13 months, the last time Jupiter was this close to Earth was in 1963, according to a NASA blog. Jupiter passing this close to Earth while in opposition is rare.
Those hoping to capture the bright and relatively close Jupiter can simply gaze at the eastern horizon around sunset in the days leading up to September 26, that same date, and the days thereafter, which should allow for naked eye viewing of the planet.
However, the close approach and opposition will allow for even more striking views of Jupiter for those with access to telescopes or other optical equipment. You don’t need a lot of zoom for Jupiter and some of her over 50 moons to put on a good show.
“With good binoculars, the bands (at least the central band) and three or four Galilean satellites (moons) should be visible,” continued Dr. Kobelski in his statement. “It is important to remember that Galileo observed these moons with 17th century optics.”
The Galilean moons are the largest natural satellites of Jupiter, Io, Europa, Ganeymede and Callisto. NASA’s Europa Clipper mission could be launched on its way to the frozen moon, which scientists say hosts a global underground ocean, as early as October 20204.
Those who want to take an even closer look should consider a telescope of at least 4 inches or larger, according to Dr. Kobelski, and possibly green and blue filters; these will improve the visibility of Jupiter’s Great Red Spot and the bandaging of the cloud layers of the great gas giant planet.
“The views should be great for a few days before and after September 26,” said Dr. Kobelski. “So, take advantage of the good weather on either side of this date to take in the view.”