NASA has launched a high-resolution picture taken by the Juno deep house probe throughout its shut encounter with Jupiter’s moon Io on December 30, 2023. The picture of the volcanic satellite tv for pc not solely exhibits exceptional particulars, however an traditional sort of lighting.
When the robotic Juno orbiter zoomed previous Io in December, it was the closest flyby of the moon for the reason that Galileo mission over 20 years in the past. It additionally marked a generational bounce in photographic functionality due to its JunoCam, which might handle a decision of 15 km/pixel (9.3 miles/pixel) from 4,300 km (2,700 miles).
As Juno handed over the southern hemisphere of Io, JunoCam despatched again high-resolution photographs of most of the moon’s options, together with energetic volcanoes spewing clouds of sulfur into house.
Nonetheless, the newest processed picture showcases an odd phenomenon. We’re used to seeing objects in house starkly lit by the Solar on one facet and sitting in jet-black darkness on the opposite. The brand new picture exhibits one facet of Io brightly lit, however the night time facet is sort of as brilliant. It’s because the brighter facet is illuminated by the Solar, whereas the opposite is lit by “Juptershine” – that’s, daylight mirrored by Jupiter again at Io.
You possibly can see the same factor throughout a New Moon. Although the Moon ought to be in full darkness, it is truly very dimly lit by Earthlight. When there is a New Moon, the Moon sees a full Earth, so lots of daylight is being mirrored onto it – sufficient to be seen on Earth below the proper situations.
After all, since Jupiter has eleven instances the diameter of Earth, Io will get virtually as a lot gentle from it as from the Solar.