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=high">atmosphere</a> shows a striped pattern of <a href="/neptune/atmosphere/N_clouds_overview.html&edu=high">clouds</a>. This cloud pattern is very similar to that of <a href="/jupiter/jupiter.html&edu=high">Jupiter</a> and <a href="/saturn/saturn.html&edu=high">Saturn</a>. Neptune even has a <a href="/neptune/atmosphere/N_clouds_GDS.html&edu=high">Great Dark Spot</a> similar to Jupiter's <a href="/jupiter/atmosphere/J_clouds_GRS.html&edu=high">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=high">ozone layer on Earth</a>, in the <a href="/physical_science/chemistry/methane.html&edu=high">methane</a> cloud deck of Neptune.<p><small><em>Image courtesy of NASA</em></small></p>This dramatic view of Jupiter's <a href="/jupiter/atmosphere/J_clouds_GRS.html&edu=high">Great Red Spot</a> and its surroundings was obtained by <a href="/space_missions/voyager.html&edu=high">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>This historic image is the first ever taken from a spacecraft in orbit about <a href="/mercury/mercury.html&edu=high">Mercury</a>, the innermost planet of the solar system. Taken on 3/29/2011 by <a href="/space_missions/robotic/messenger/messenger.html&edu=high">MESSENGER</a>, it shows numerous craters across the <a href="/mercury/Interior_Surface/Surface/surface_overview.html&edu=high">surface</a> of the planet. Temperatures there can reach over 800F 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>New observations by the MESSENGER spacecraft provide support for the hypothesis that Mercury harbors abundant water ice and other frozen volatile materials in its permanently shadowed (shown in red) polar craters. Areas where polar deposits of ice imaged by Earth-based radar are shown in yellow.<p><small><em>Image courtesy of NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/National Astronomy and Ionosphere Center, Arecibo Observatory</em></small></p>Comets are <a href="/comets/comet_nucleus.html&edu=high">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=high">outer reaches</a>. Some comets make <a href="/comets/perihelion_pass.html&edu=high">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=high">evaporate</a>. Jets of gas and dust form long <a href="/comets/tail.html&edu=high">tails</a> that we can see from Earth. This photograph shows <a href="/comets/comets_table.html&edu=high">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=high">orbit</a> of about 75,000 years!<p><small><em>Image courtesy of NASA</em></small></p>According to <a href="http://www.jpl.nasa.gov/news/news.php?release=2013-277">NASA scientists</a>, the Voyager 1 spacecraft entered interstellar space in August 2012, becoming the first spacecraft to leave the <a href="/our_solar_system/solar_system.html&edu=high">solar system</a>. The space probe is about 19 billion km from the <a href="/sun/sun.html&edu=high">Sun</a>. <a href="/space_missions/voyager.html&edu=high">Voyager 1 and 2</a> were launched in 1977 on a <a href="/space_missions/voyager.html&edu=high">mission</a> that flew them both by <a href="/jupiter/jupiter.html&edu=high">Jupiter</a> and <a href="/saturn/saturn.html&edu=high">Saturn</a>, with Voyager 2 continuing to <a href="/uranus/uranus.html&edu=high">Uranus</a> and <a href="/neptune/neptune.html&edu=high">Neptune</a>. Voyager 2 is the longest continuously operated spacecraft. It is about 15 billion km away from the <a href="/sun/sun.html&edu=high">Sun</a>.<p><small><em>Image courtesy of NASA</em></small></p>

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 long ago, many people thought that comets were a portent that something bad was about ...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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Did you know?

Did you know that a moon has been found to orbit the asteroid Eugenia?

Did you know that bodies in the solar system orbit the Sun in elliptical orbits?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Umbra
xUmbra : The shadow cast by a celestial body

Click on the word to find out!

Research Highlights

Soil Microbes Produce Less Atmospheric Carbon Dioxide Than Expected With Global Warming

In dark, rich soils on every continent, microbes dealing with the effects of climate change aren't accelerating global warming the way scientists had predicted, a study by researchers at the University...Read more


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