Our Solar System

Our solar system is filled with a wide assortment of celestial bodies - the Sun itself, our eight planets, dwarf planets, and asteroids - and on Earth, life itself! The inner solar system is occasionally visited by comets that loop in from the outer reaches of the solar system on highly elliptical orbits. In the outer reaches of the solar system, we find the Kuiper Belt and the Oort cloud. Still farther out, we eventually reach the limits of the heliosphere, where the outer reaches of the solar system interact with interstellar space. Solar system formation began billions of years ago, when gases and dust began to come together to form the Sun, planets, and other bodies of the solar system.

Neptune's <a href="/neptune/lower_atmosphere.html&edu=elem">atmosphere</a> shows a striped pattern of <a href="/neptune/atmosphere/N_clouds_overview.html&edu=elem">clouds</a>. This cloud pattern is very similar to that of <a href="/jupiter/jupiter.html&edu=elem">Jupiter</a> and <a href="/saturn/saturn.html&edu=elem">Saturn</a>. Neptune even has a <a href="/neptune/atmosphere/N_clouds_GDS.html&edu=elem">Great Dark Spot</a> similar to Jupiter's <a href="/jupiter/atmosphere/J_clouds_GRS.html&edu=elem">Great Red Spot</a>. The Great Dark Spot of Neptune is thought to be a hole, similar to the hole in the <a href="/earth/Atmosphere/ozone_layer.html&edu=elem">ozone layer on Earth</a>, in the <a href="/physical_science/chemistry/methane.html&edu=elem">methane</a> cloud deck of Neptune.<p><small><em>Image courtesy of NASA</em></small></p>Lunar eclipses are special events that only occur when certain conditions are met. First of all, the Moon must be in <a href="/the_universe/uts/moon3.html&edu=elem">full phase</a>. Secondly, the <a href="/sun/sun.html&edu=elem">Sun</a>, <a href="/earth/earth.html&edu=elem">Earth</a> and <a href="/earth/moons_and_rings.html&edu=elem">Moon</a> must be in a perfectly straight line. If both of these are met, then the Earth's shadow can block the Sun's light from hitting the Moon. The reddish glow of the Moon is caused by light from the Earth's limb scattering toward the Moon, which is reflected back to us from the Moon's surface.<p><small><em>Image credit - Doug Murray, Palm Beach Gardens, Florida</em></small></p><a href="/asteroids/asteroid_lutetia.html&edu=elem">Lutetia</a> is a medium-sized <a href="/our_solar_system/asteroids.html&edu=elem">asteroid</a>. It orbits the <a href="/sun/sun.html&edu=elem">Sun</a> in the main asteroid belt between the planets <a href="/mars/mars.html&edu=elem">Mars</a> and <a href="/jupiter/jupiter.html&edu=elem">Jupiter</a>. This lumpy object is about 96 km (60 miles) in diameter. It isn't a perfect sphere, though. Lutetia is 132 km (82 miles) across one way, but only about 76 km (47 miles) long in another direction. The European space probe <a href="/space_missions/robotic/rosetta_flyby_asteroid_lutetia_july_2010.html&edu=elem">Rosetta flew past Lutetia</a> in July 2010, and gave us our first good look at the asteroid.<p><small><em>Image courtesy of ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA.</em></small></p>This historic image is the first ever taken from a spacecraft in orbit about <a href="/mercury/mercury.html&edu=elem">Mercury</a>, the innermost planet of the solar system. Taken on 3/29/2011 by <a href="/space_missions/robotic/messenger/messenger.html&edu=elem">MESSENGER</a>, it shows numerous craters across the <a href="/mercury/Interior_Surface/Surface/surface_overview.html&edu=elem">surface</a> of the planet. Temperatures there can reach over 800°F because Mercury is so close to the Sun and rotates so slowly. MESSENGER entered orbit around Mercury earlier in March 2011.<p><small><em>NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington</em></small></p>This dramatic view of Jupiter's <a href="/jupiter/atmosphere/J_clouds_GRS.html&edu=elem">Great Red Spot</a> and its surroundings was obtained by <a href="/space_missions/voyager.html&edu=elem">Voyager 1</a> on Feb. 25, 1979, when the spacecraft was 5.7 million miles (9.2 million kilometers) from Jupiter. Cloud details as small as 100 miles (160 kilometers) across can be seen here. The colorful, wavy cloud pattern to the left of the Red Spot is a region of extraordinarily complex end variable wave motion.<p><small><em>Image courtesy of NASA</em></small></p>Comets are <a href="/comets/comet_nucleus.html&edu=elem">lumps</a> of ice and dust that periodically come into the center of the solar system from its <a href="/comets/Oort_cloud.html&edu=elem">outer reaches</a>. Some comets make <a href="/comets/perihelion_pass.html&edu=elem">repeated trips</a> to the inner solar system. When comets get close enough to the Sun, heat makes them start to <a href="/comets/sublimation.html&edu=elem">evaporate</a>. Jets of gas and dust form long <a href="/comets/tail.html&edu=elem">tails</a> that we can see from Earth. This photograph shows <a href="/comets/comets_table.html&edu=elem">Comet Kohoutek</a>, which visited the inner solar system in 1973. It has an <a href="/physical_science/physics/mechanics/orbit/orbit_shape_interactive.html&edu=elem">orbit</a> of about 75,000 years!<p><small><em>Image courtesy of NASA</em></small></p>

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Explore Our Solar System

Solar System Formation

Solar system formation began billions of years ago, when gases and dust began to come together ...Read more

Sun

The Sun is the closest star to Earth and is the center of our solar system. A giant, spinning ...Read more

Planets

By the current count of astronomers, our solar system includes 8 planets and 5 dwarf planets. ...Read more

Dwarf Planets

In 2006 the International Astronomical Union (IAU) approved a new classification scheme for ...Read more

Asteroids

Asteroids are small bodies that are believed to be left over from the beginning of the solar ...Read more

Meteors, Meteoroids, and Meteorites

Meteors are streaks of light, usually lasting just a few seconds, which people occasionally ...Read more

Comets

Not too long ago, many people thought that comets were a sign that something terrible was ...Read more

Poles in Space

The areas around the North and South Poles of planets, moons, and even the Sun are often interesting ...Read more

Culture, Myth, and Arts

Make important cultural connections about the Sun, planets, and the Moon. ...Read more

Solar System Discoveries

Who discovered the planets? For many of the planets in the solar system, we'll never know! ...Read more

More about Our Solar System

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Do you know the difference between meteors, meteoroids, and meteorites?

Do you know what Pluto, Ceres, Haumea, Makemake, and Eris have in common?

 

Earth and Space Science Concept of the Day

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Magnetic polarity reversal
xMagnetic polarity reversal : A magnetic polarity reversal is a change of the earth's magnetic field to the opposite polarity. This has occurred at irregular intervals during geologic time.

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Research Highlights

Geologists Uncover Major Ancient Human Ancestor in South Africa

Scientists in South Africa have discovered two fossil skeletons that are about two million years old. These skeletons are of a young male and adult female of a species that had never been found before....Read more

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