Watch JUICE next week during its flyby between Earth and the Moon

Well-placed observers will have a rare chance to spot an interplanetary spacecraft early next week.

If skies are clear, dedicated observers and imagers will have a chance early next week to see a spacecraft heading toward Jupiter.

The mission is JUICE, the European Space Agency's Jupiter Icy Moons Explorer. It was launched aboard an Ariane-5 rocket from the Kourou Space Centre in French Guiana on April 14.^HeJUICE is scheduled to reach Jupiter in 2023, but will first perform several planetary flybys to gain speed and head toward the outer solar system.

Firsts for ESA

JUICE marks several firsts for space exploration and ESA. JUICE is the first non-NASA solo mission to the outer Solar System, as well as ESA’s first mission to Jupiter. The mission also follows in the footsteps of NASA’s Juno mission, using massive solar arrays instead of a nuclear-powered MMRTG for power.

In another first, JUICE will perform the The first flyby of Earth and the Moon for this next push. It's a challenging, “threading the needle” maneuver, as the Moon flyby prepares the spacecraft for the Earth flyby. The maneuver is called “LEGA,” or Moon-Earth Gravity Assist. JUICE started its engines for 43 minutes last year to prepare for this month's flyby of Earth and Moon. A series of Four smaller course correction burns They were carried out recently, beginning with a 31-second maneuver on July 22.^{North Dakota}.

The big test for the spacecraft will come in 2031, when JUICE fires its main engines for orbit insertion around Jupiter. The trick during any firing of the spacecraft's engines is not to induce any unwanted oscillations in the massive, cross-shaped solar panels.

The double flyby is a fortuitous result of the 2023 launch window. The first flyby of the Moon gives engineers a chance to fine-tune the Earth pass shortly before closest approach if needed. The spacecraft's total delta-V maximum velocity is 2,700 meters per second, or 6,000 miles per hour.

JUICE was even briefly wrong for a potentially hazardous asteroid approaching earlier this month. The spacecraft poses no danger to the Earth-Moon system.

Flyby preview

The details of the meeting are as follows:

The Moon's closest approach will occur on Monday, August 19.^He at 21:16 Universal Time (UT), 700 kilometers from the lunar surface.

The closest approach to Earth will occur about 24 hours later, on Tuesday, August 20.^He at 21:57 UT. At its closest point, JUICE will pass within 6,807 kilometers (4,200 miles) of Earth's surface over northeast Asia and the Pacific. This encounter occurs during daylight. Australia and Southeast Asia have the best chance of seeing JUICE approaching just before the point of closest approach in the pre-dawn sky.

In Europe and North America, circumstances are less favorable. In these locations, the spacecraft will appear farther away when it is higher in the sky. For example, in Paris, the spacecraft will be seen at a distance of 220,000 miles/354,000 kilometers. In Boston, JUICE will be seen at a distance of 150,000 miles/241,000 kilometers around 6:20 UT in the predawn sky.

The JUICE mission of @that It is returning to Earth this month to receive a gravitational assist from both the Moon and Earth. It is headed to Jupiter, where it will study its moons and even orbit Ganymede before crashing into it. @ESA_JUICE image.twitter.com/5C3OUkkJ0J

— Tony Dunn (@tony873004) August 4, 2024

The southeastern US will get another chance around 1:00 UT on August 21.^street (9:00 p.m. Eastern Daylight Time, August 20)^HeThis opportunity to reach the horizon at close range occurs at dusk, when the spacecraft is about 30,000 miles away.

ESA’s ESOC (European Space Operations Centre) and the global Estrack network will track JUICE throughout the flyby. This will also give mission controllers a chance to test key instruments, which will be switched on during the flyby. Of particular interest is the RIME (Radar for the Exploration of Icy Moons) instrument. RIME appears to be receiving interference from other instruments on the spacecraft. Controllers will use it both in solo mode and in tandem with other onboard instruments during the lunar flyby, in an effort to troubleshoot RIME. RIME is crucial for probing the interior of Jupiter’s icy moons.

Detecting JUICE

The key to locating JUICE is knowing where and when to look. JUICE is 90 feet (27 meters) wide from the tip of one solar panel to the tip of another, and will pass by Earth within range of the ring of geostationary satellites. A good specular flare from the Sun on one of the large solar panels could temporarily boost JUICE's brightness to within range of the naked eye.

Obtaining an accurate position from JUICE is complicated, as most planetary programs do not include the deflection of the spacecraft due to the gravity of the Earth and Moon. Generating ephemerides with JPL Horizons is your best bet, as it will give you an accurate position in the sky in Right Ascension (RA) and Declination to aim and search. Simply observe at the indicated time and try to “ambush” JUICE as it glides by. Much like a satellite, JUICE will look like a moving “star” drifting across the background field of fixed stars.

JUICE is the ID-28 spacecraft in JPL's Horizon System.

Astronomer Gianluca Masi I saw JUICE During a Virtual Telescope session on August 9^He:

The heavens above They may post JUICE tracking maps. They have done so in the past… we'll post them here this weekend if they appear.

Next, JUICE will fly by Venus next August. It will then conduct two more flybys of Earth, one in 2026 and one in 2029.

Good luck and clear skies on your quest to catch JUICE on this historic flyby of the Earth to the Moon.