Now that NASA’s Juno spacecraft is orbiting Jupiter and sending us spectacular pictures, especially of its polar regions, we can enjoy a happy coincidence: On this Saturday night, June 3, 2017, Jupiter will form a dramatic tight conjunction with the Moon.
This Jupiter-Moon conjunction isn’t one of those pre-dawn, insomniac affairs. The Moon and Jupiter are highest up and closest together at nightfall, and can be seen even in evening twilight. Simply venture out after sunset and find the Moon. Jupiter is that brilliant “star” just below it.
Turns out, both look great through any small telescope. This is the time of the lunar month when the lunar shadowing is perfect, showing off the Moon’s craters and the cool mountain range just above its center, the Lunar Apennines. As for Jupiter, what you see depends on the quality of the scope and the steadiness of the air that night. If the stars are twinkling crazily, forget the whole idea: Jupiter will be a blurry mess. But if the stars are steady, you’ll first see its two main dark belts, followed by all sorts of swirls, festoons, and other detail. And its four huge moons are doing strange things then, too.
Look for Jupiter’s Moons
At nightfall in the Eastern half of the U.S. and Canada, only two of Jupiter’s moons are visible, on the planet’s right side. (Telescopes usually flip the image upside down, so for you they might seem to be on the left side). But look more closely. The innermost moon, the famous volcano-covered Io, is actually parading in front of Jupiter, and is superimposed on its disk! And the satellite Europa—the one with the under-ice oceans that might have life—is behind Jupiter.
At around 9:40 EDT, Europa emerges from behind Jupiter, but may still be hidden because it is now immersed in Jupiter’s shadow! About an hour later, Io emerges from in front of Jupiter and can now be seen against a black sky. Finally, a few minutes before midnight, Europa comes out of Jupiter’s shadow and blazes gloriously, alone on Jupiter’s left side. (Or right side, if the image is upside down). Even high-power binoculars can show the action, especially the image-stabilized models.
Jupiter’s South Pole. The oval features are cyclones. CreditNASA/JPL-Caltech
News about Jupiter!
Have your heard that brand-new findings have been revealed about the Giant Planet? NASA’s Juno Mission reached Jupiter last July. Many of our assumptions about Jupiter were incorrect, so it’s a grand ever-evolving discovery. Here are some highlights:
- The famous belt of clouds and zones of color may only be on the top surface that we see from Earth.
- Beneath that cloud cover are wells of ammonia that form giant and violent weather systems in the deep atmosphere.
- Bright ovals at the poles revealed giant cyclones bigger than Earth!
- Jupiter’s magnetic field is twice as powerful as predicted and 10 times more powerful than Earth’s strongest magnetic field.
- Auroras seem to work in the opposite way than those seen from Earth, with an electron beam pushing energy out of the planet into space!
- The gas giant may not be completely gas after all. It seems to be not a rocky core nor hydrogen gas, but a “fuzzy core” that may be both.
The next Juno flyby will happen July 11 and go directly over the Great Red Spot. Stay tuned.
Until then, this Saturday is a “don’t miss” night. Even if all you have are your baby blues, the conjunction alone is worth a look.
See more This Week’s Amazing Sky blogs.