Galileo was an American robotic space program that studied the planet Jupiter and its moons, as well as several other Solar System bodies. Named after the Italian astronomer Galileo Galilei, the Galileo spacecraft consisted of an orbiter and an entry probe. It was delivered into Earth orbit on October 18, 1989 by Space ShuttleAtlantis on the STS-34 mission, and arrived at Jupiter on December 7, 1995, after gravitational assist flybys of Venus and Earth, and became the first spacecraft to orbit Jupiter. It launched the first probe into Jupiter, directly measuring its atmosphere. Despite suffering major antenna problems, Galileo achieved the first asteroid flyby, of 951 Gaspra, and discovered the first asteroid moon, Dactyl, around 243 Ida. In 1994, Galileo observed Comet Shoemaker–Levy 9's collision with Jupiter.
Pioneer 10 is a NASA space probe launched in 1972 that completed the first mission to the planet Jupiter. Pioneer 10 became the first of five planetary probes and 11 artificial objects to achieve the escape velocity needed to leave the Solar System. This space exploration project was conducted by the NASA Ames Research Center in California. The space probe was manufactured by TRW Inc.
Ganymede, or Jupiter III, is the largest and most massive natural satellite of Jupiter as well as the largest in the Solar System, being a planetary-mass moon. It is the largest Solar System object without a substantial atmosphere, despite being the only moon in the Solar System with a substantial magnetic field. Like Titan, Saturn's largest moon, it is larger than the planet Mercury, but has somewhat less surface gravity than Mercury, Io, or the Moon due to its lower density compared to the three.
Io, or Jupiter I, is the innermost and second-smallest of the four Galilean moons of the planet Jupiter. Slightly larger than Earth's moon, Io is the fourth-largest moon in the Solar System, has the highest density of any moon, the strongest surface gravity of any moon, and the lowest amount of water by atomic ratio of any known astronomical object in the Solar System. It was discovered in 1610 by Galileo Galilei and was named after the mythological character Io, a priestess of Hera who became one of Zeus's lovers.
Juno is a NASA space probe orbiting the planet Jupiter. It was built by Lockheed Martin and is operated by NASA's Jet Propulsion Laboratory. The spacecraft was launched from Cape Canaveral Air Force Station on August 5, 2011 UTC, as part of the New Frontiers program. Juno entered a polar orbit of Jupiter on July 5, 2016, UTC, to begin a scientific investigation of the planet. After completing its mission, Juno will be intentionally deorbited into Jupiter's atmosphere.
The magnetosphere of Jupiter is the cavity created in the solar wind by Jupiter's magnetic field. Extending up to seven million kilometers in the Sun's direction and almost to the orbit of Saturn in the opposite direction, Jupiter's magnetosphere is the largest and most powerful of any planetary magnetosphere in the Solar System, and by volume the largest known continuous structure in the Solar System after the heliosphere. Wider and flatter than the Earth's magnetosphere, Jupiter's is stronger by an order of magnitude, while its magnetic moment is roughly 18,000 times larger. The existence of Jupiter's magnetic field was first inferred from observations of radio emissions at the end of the 1950s and was directly observed by the Pioneer 10 spacecraft in 1973.
The exploration of Jupiter has been conducted via close observations by automated spacecraft. It began with the arrival of Pioneer 10 into the Jovian system in 1973, and, as of 2023, has continued with eight further spacecraft missions in the vicinity of Jupiter. All of these missions were undertaken by the National Aeronautics and Space Administration (NASA), and all but two were flybys taking detailed observations without landing or entering orbit. These probes make Jupiter the most visited of the Solar System's outer planets as all missions to the outer Solar System have used Jupiter flybys. On 5 July 2016, spacecraft Juno arrived and entered the planet's orbit—the second craft ever to do so. Sending a craft to Jupiter is difficult, mostly due to large fuel requirements and the effects of the planet's harsh radiation environment.
Io Volcano Observer (IVO) is a proposed low-cost mission to explore Jupiter's moon Io to understand tidal heating as a fundamental planetary process. The main science goals are to understand (A) how and where tidal heat is generated inside Io, (B) how tidal heat is transported to the surface, and (C) how Io is evolving. These results are expected to have direct implications for the thermal history of Europa and Ganymede as well as provide insights into other tidally heated worlds such as Titan and Enceladus. The IVO data may also improve our understanding of magma oceans and thus the early evolution of the Earth and Moon.
The exploration of Io, Jupiter's innermost Galilean and third-largest moon, began with its discovery in 1610 and continues today with Earth-based observations and visits by spacecraft to the Jupiter system. Italian astronomer Galileo Galilei was the first to record an observation of Io on January 8, 1610, though Simon Marius may have also observed Io at around the same time. During the 17th century, observations of Io and the other Galilean satellites helped with the measurement of longitude by map makers and surveyors, with validation of Kepler's Third Law of planetary motion, and with measurement of the speed of light. Based on ephemerides produced by astronomer Giovanni Cassini and others, Pierre-Simon Laplace created a mathematical theory to explain the resonant orbits of three of Jupiter's moons, Io, Europa, and Ganymede. This resonance was later found to have a profound effect on the geologies of these moons. Improved telescope technology in the late 19th and 20th centuries allowed astronomers to resolve large-scale surface features on Io as well as to estimate its diameter and mass.
Laplace-P was a proposed orbiter and lander by the Russian Federal Space Agency designed to study the Jovian moon system and explore Ganymede with a lander.
The Jupiter Icy Moons Explorer is an interplanetary spacecraft that was launched on 14 April 2023 from Guiana Space Centre in the French Guiana by the European Space Agency (ESA) with Airbus Defence and Space as the main contractor. The mission is planned to study Ganymede, Callisto, and Europa, three of Jupiter's Galilean moons. They are thought to have significant bodies of liquid water beneath their icy surfaces which would make them potentially habitable environments.
Jovian Infrared Auroral Mapper (JIRAM) is an instrument on the Juno spacecraft in orbit of the planet Jupiter. It is an image spectrometer and was contributed by Italy. Similar instruments are on ESA Rosetta, Venus Express, and Cassini-Huygens missions. The primary goal of JIRAM is to probe the upper layers of Jupiter's atmosphere down to pressures of 5–7 bars at infrared wavelengths in the 2–5 μm interval using an imager and a spectrometer. The Jupiter's atmosphere and auroral regions are targeted for study. In particular it has been designed to study the dynamics and chemistry in the atmosphere, perhaps determining the how Jovian hot spots form.
JEDI (Jupiter Energetic-particle Detector Instrument) is an instrument on the Juno spacecraft orbiting planet Jupiter. JEDI coordinates with the several other space physics instruments on the Juno spacecraft to characterize and understand the space environment of Jupiter's polar regions, and specifically to understand the generation of Jupiter's powerful aurora. It is part of a suite of instruments to study the magnetosphere of Jupiter. JEDI consists of three identical detectors that use microchannel plates and foil layers to detect the energy, angle, and types of ion within a certain range. It can detect electrons between 40 and 500 keV (Kilo electron-volts), and hydrogen and oxygen from a few tens of keV to less than 1000 keV (1 MeV). JEDI uses radiation hardened Application Specific Integrated Circuits (ASIC)s. JEDI was turned on in January 2016 while still en route to Jupiter to also study interplanetary space. JEDI uses solid state detectors (SSD's) to measure the total energy (E) of both the ions and the electrons. The MCP anodes and the SSD arrays are configured to determine the directions of arrivals of the incoming charged particles. The instruments also use fast triple coincidence and optimum shielding to suppress penetrating background radiation and incoming UV foreground.
Europa Clipper is an interplanetary mission in development by NASA comprising an orbiter. Planned for launch in October 2024, the spacecraft is being developed to study the Galilean moon Europa through a series of flybys while in orbit around Jupiter.
The timeline of the Galileo spacecraft spans its launch in 1989 to the conclusion of its mission when it dove into and destroyed itself in the atmosphere of Jupiter in 2003.
UVS, known as the Ultraviolet Spectrograph or Ultraviolet Imaging Spectrometer is the name of an instrument on the Juno orbiter for Jupiter. The instrument is an imaging spectrometer that observes the ultraviolet range of light wavelengths, which is shorter wavelengths than visible light but longer than X-rays. Specifically, it is focused on making remote observations of the aurora, detecting the emissions of gases such as hydrogen in the far-ultraviolet. UVS will observes light from as short a wavelength as 70 nm up to 200 nm, which is in the extreme and far ultraviolet range of light. The source of aurora emissions of Jupiter is one of the goals of the instrument. UVS is one of many instruments on Juno, but it is in particular designed to operate in conjunction with JADE, which observes high-energy particles. With both instruments operating together, both the UV emissions and high-energy particles at the same place and time can be synthesized. This supports the Goal of determining the source of the Jovian magnetic field. There has been a problem understanding the Jovian aurora, ever since Chandra determined X-rays were coming not from, as it was thought Io's orbit but from the polar regions. Every 45 minutes an X-ray hot-spot pulsates, corroborated by a similar previous detection in radio emissions by Galileo and Cassini spacecraft. One theory is that its related to the solar wind. The mystery is not that there are X-rays coming Jupiter, which has been known for decades, as detected by previous X-ray observatories, but rather why with the Chandra observation, that pulse was coming from the north polar region.
Waves is an experiment on the Juno spacecraft to study radio and plasma waves. It is part of collection of various types of instruments and experiments on the spacecraft; Waves is oriented towards understanding fields and particles in Jupiter's magnetosphere. Waves is on board the uncrewed Juno spacecraft, which was launched in 2011 and arrived at Jupiter in the summer of 2016. The major focus of study for Waves is Jupiter's magnetosphere, which if could be seen from Earth would be about twice the size of a full moon. It has a tear drop shape, and that tail extends away from the Sun by at least 5 AU. The Waves instrument is designed to help understand the interaction between Jupiter's atmosphere, its magnetic field, its magnetosphere, and to understand Jupiter's auroras. It is designed to detect radio frequencies from 50 Hz up to 40,000,000 Hz (40 MHz), and magnetic fields from 50 Hz to 20,000 Hz (20 kHz). It has two main sensors a dipole antenna and a magnetic search coil. The dipole antenna has two whip antenna's that extend 2.8 meters and they are attached to the main body of the spacecraft. This sensor has been compared to a rabbit ears set-top TV antenna. The search coil is overall a mu metal rod 15 cm (6 in) length with a fine copper wire wound 10,000 times around it. There are also two frequency receivers that each cover certain bands. Data handling is done by two radiation hardened systems on a chip. The data handling units are located inside the Juno Radiation Vault. Waves was allocated 410 Mbits of data per science orbit.
Juno Radiation Vault is a compartment inside the Juno spacecraft that houses much of the probe's electronics and computers, and is intended to offer increased protection of radiation to the contents as the spacecraft endures the radiation environment at planet Jupiter. The Juno Radiation Vault is roughly a cube, with walls made of 1 cm thick titanium metal, and each side having an area of about a square meter. The vault weighs about 200 kg (500 lbs). Inside the vault are the main command and data handling and power control boxes, along with 20 other electronic boxes. The vault should reduce the radiation exposure by about 800 times, as the spacecraft is exposed to an anticipated 20 million rads of radiation It does not stop all radiation, but significantly reduces it in order to limit damage to the spacecraft's electronics.
Ralph is a science instrument aboard the robotic New Horizons spacecraft, which was launched in 2006. Ralph is a visible and infrared imager and spectrometer to provide maps of relevant astronomical targets based on data from that hardware. Ralph has two major subinstruments, LEISA and MVIC. MVIC stands for Multispectral Visible Imaging Camera and is a color imaging device, while LEISA originally stood for Linear Etalon Imaging Spectral Array and is an infrared imaging spectrometer for spaceflight. LEISA observes 250 discrete wavelengths of infrared light from 1.25 to 2.5 micrometers. MVIC is a pushbroom scanner type of design with seven channels, including red, blue, near-infrared (NIR), and methane.
Tianwen-4, formerly known as Gan De, is a planned interplanetary mission by China to study the Jovian system and its environs, sharing a launch with a spacecraft which will make a flyby of Uranus.
