Biggest planets
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The Largest Planets in Our Solar System and Beyond
Gas Giants in Our Solar System: Jupiter and Saturn
Jupiter: The Largest Planet
Jupiter is the largest and most massive planet in our solar system. It is primarily composed of hydrogen and helium, similar to a star, but it did not grow massive enough to ignite nuclear fusion. NASA's Juno spacecraft has provided detailed observations of Jupiter, revealing its complex weather systems, magnetic fields, and deep atmospheric structures4 6 7. With a diameter of about 143,000 kilometers, Jupiter dwarfs all other planets in the solar system2 3.
Saturn: The Second Largest Planet
Saturn, the second largest planet, is also a gas giant primarily composed of hydrogen and helium. It has a diameter of approximately 120,000 kilometers and is known for its extensive and visually stunning ring system. Saturn's mass is about 95 times that of Earth, but it has a very low density, even less than water5. Like Jupiter, Saturn has a rich system of moons and rings, contributing to its unique characteristics2 3.
Other Giant Planets: Uranus and Neptune
Uranus and Neptune: The Ice Giants
Uranus and Neptune, often referred to as ice giants, are also among the largest planets in our solar system. Unlike Jupiter and Saturn, they contain a higher proportion of "ices" such as water, ammonia, and methane. These substances exist in a high-pressure state within their interiors. Both planets have diameters around 50,000 kilometers and are located much farther from the Sun, between 19 and 30 astronomical units (AU)2 3.
Exoplanets: The Largest Planets Beyond Our Solar System
Kepler-1647b: The Largest Circumbinary Planet
Kepler-1647b is the largest known circumbinary planet, meaning it orbits two stars. This planet has a radius of 1.06 times that of Jupiter and an orbital period of approximately 1100 days. It is notable for being in the habitable zone of its binary star system, despite its long orbital period1.
HATS-74Ab, HATS-75b, HATS-76b, and HATS-77b: Giant Planets Around Low-Mass Stars
Recent discoveries include four gas giant planets—HATS-74Ab, HATS-75b, HATS-76b, and HATS-77b—orbiting low-mass stars. These planets have masses ranging from 0.491 to 2.629 times that of Jupiter and radii close to that of Jupiter. They orbit their host stars very closely, with periods ranging from 1.73 to 3.09 days8.
Conclusion
The largest planets in our solar system, Jupiter and Saturn, are gas giants with extensive systems of moons and rings. Uranus and Neptune, the ice giants, also rank among the largest planets but have different compositions. Beyond our solar system, exoplanets like Kepler-1647b and the HATS series of planets demonstrate the diversity and scale of giant planets in the universe. These discoveries continue to expand our understanding of planetary formation and the characteristics of giant planets both near and far.
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KEPLER-1647B: THE LARGEST AND LONGEST-PERIOD KEPLER TRANSITING CIRCUMBINARY PLANET
Kepler-1647b is the largest and longest-period transiting circumbinary planet, orbiting an 11-day period eclipsing binary with a mass of 1.52 0.65 MJup, and is in the habitable zone of the binary star throughout its orbit.
Highly CitedJupiter’s interior and deep atmosphere: The initial pole-to-pole passes with the Juno spacecraft
Juno's first close pass over Jupiter revealed chaotic weather, a rich harmonic magnetic field, and a more precise gravity field, impacting the distribution of heavy elements and the existence of Jupiter's core.
Highly CitedJupiter’s magnetosphere and aurorae observed by the Juno spacecraft during its first polar orbits
The Juno spacecraft has made first-ever observations of Jupiter's magnetosphere and aurorae, providing insights into the processes driving these phenomena.
Highly CitedHATS-74Ab, HATS-75b, HATS-76b, and HATS-77b: Four Transiting Giant Planets Around K and M Dwarfs
Four gas giant planets have been discovered orbiting low-mass K and M dwarfs, challenging the core-accretion theory and potentially confirming the theory's predictions.
Two Earth-sized planets orbiting Kepler-20
Two Earth-sized and smaller planets have been discovered orbiting Kepler-20, with the likelihood of their being rocky and possibly with thick water vapour atmospheres.
Highly CitedThe L 98-59 System: Three Transiting, Terrestrial-size Planets Orbiting a Nearby M Dwarf
Three terrestrial-size planets have been discovered orbiting a nearby M dwarf, offering a unique opportunity to study planetary system dynamics and evolution.
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