JUICE, launched in April 2023, is the first European mission to Jupiter, tasked with studying the planet and its largest moons: Ganymede, Callisto and Europa.

These moons are thought to have subsurface oceans beneath their icy crusts, making them key targets in the quest to understand more about possible extraterrestrial life.

When and how can you detect JUICE?

The close flyby of Earth will occur at 5:57 p.m. Eastern Time (21:57 GMT) on August 20.

This will help adjust the spacecraft’s trajectory through a gravity-assisted maneuver.

This flyby, along with a planned future flyby of Venus and two additional passes by Earth, is essential to putting JUICE on course to reach Jupiter in 2031.

The European Space Agency (ESA) has said that powerful binoculars or a telescope will offer the best chance of observing the spacecraft.

Why is flyby important?

The flyby will be a crucial test for JUICE’s instruments. In particular, the RIME (Radar for the Exploration of the Icy Moon) antenna, which had deployment and electronic noise problems, will be activated for a performance check.

Engineers will have an eight-minute window on August 19 to assess RIME’s functionality and potentially adjust its operations.

“These maneuvers are like navigating at high speed through a narrow corridor,” said Ignacio Tanco, the mission’s operations manager, who highlighted the precision required for a successful execution, given the narrow margin of error.

Ground stations around the world will be in constant communication with JUICE beginning August 17, monitoring the spacecraft’s progress and making adjustments as necessary.

JUICE will also fly beyond the moon:

Before reaching Earth, JUICE will fly by Earth’s moon on August 19. The spacecraft will then approach Earth, with its closest view being over Southeast Asia and the Pacific Ocean.

When the probe is behind the Moon, brief interruptions in communications are expected (such as a half-hour break on August 19), which are planned for in the mission planning.

JUICE’s trip to Jupiter, which would otherwise have required 132,000 pounds (60,000 kilograms) of fuel, benefits from the gravity assist provided by flybys of the Moon and Earth.

This efficient use of fuel allows the spacecraft to carry only 8,000 pounds (3,650 kilograms) of propellant, with a reserve of 800 pounds (363 kilograms) used for trajectory adjustments.

As JUICE approaches Earth, its onboard cameras will capture images of our planet and the moon, which will be shared on social media.

(With contributions from Space.com)