The solar system is the gravitationally bound system of the sun and the objects that orbit it. Of the bodies that orbit the sun directly, the largest are the four gas and ice giants and the four terrestrial planets, followed by an unknown number of dwarf planets and innumerable small solar system bodies. Of the bodies that orbit the Sun indirectly—the natural satellites—two are larger than Mercury and one is nearly as large.
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The continent-sized cyclones at Jupiter’s poles generate strong winds and ammonia-laden storms. The spacecraft has also collected data on Jupiter’s unique magnetic field, which resembles a blend of Earth’s and Uranus/Neptune's.
Scientists from the University of Zurich and NCCR PlanetS proposed the mechanism after using computer modeling to replicate Jupiter’s formation to match its observed concentration of heavy elements. The work may help understand how Jupiter-like exoplanets exist near host stars.
Since solar winds remove gases from protoplanetary disks within millions of years of a star’s birth, models needed to provide a mechanism to jump-start Jupiter’s formation and growth. The solution involved incorporating pebbles of matter into the disk.
One theory of Jupiter’s formation involves the planet spiraling inwards from the asteroid belt, gathering material and disrupting the initial formation of terrestrial planets. Saturn’s gravitational pull would then reverse its course.
Using the JunoCam, scientists have observed several of Jupiter's features, including cyclones, the Great Red Spot, and cloud bands and zones. The mission's effectiveness has resulted in its extension from July 2021 to September 2025.
Despite decreasing in size, the anticyclone remains larger than Earth, rotating with winds up to 933 km/h. Its longevity may be because it is trapped between two opposite-flowing jet streams, which act like two conveyor belts.
Its original size was deduced from the orbits of its moons, Amalthea and Thebe. The planet's magnetic field was also 50 times stronger than today, or 400 times stronger than Earth's.
The model suggests Jupiter migrated inward early in its formation and cleared debris from the inner orbits of terrestrial planets. Saturn's gravitational pull saved what was left of the inner solar system to form Mercury, Venus, Earth, and Mars.
Jupiter's moons were first discovered on Jan. 7, 1610. They include Ganymede, the largest moon in the solar system and larger than Mercury, Io, the most volcanically active moon, and Europa, which has a saltwater ocean.
A new study suggests that Venus' co-orbital asteroids—space rocks that lag ahead or behind the planet—could potentially destroy cities if they strike Earth. While no observed co-orbitals currently pose a threat, observational bias prevents observation of those of greater risk.
From roughly 60 miles above the Earth's surface to farther than light has traveled during the entire age of the universe, space has captured human imagination for millennia. Explore the final frontier with the best resources curated from across the internet.