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.

A near-Earth <a href="/our_solar_system/asteroids.html&edu=elem&dev=1/windows.html">asteroid</a> - named 2012 DA14 by astronomers - passed within 17,200 miles from Earth on February 15, 2013. On closest approach at about 1:25 p.m. CST on February 15, although it was within the orbit of the <a href="/earth/moons_and_rings.html&edu=elem&dev=1/windows.html">Moon</a> and even geosynchronous <a href="/space_missions/satellites.html&edu=elem&dev=1/windows.html">satellites</a>, it didn't strike Earth! Find out more from <a href="http://www.nasa.gov/mission_pages/asteroids/news/asteroid20130201315144.html">NASA</a>! Fragments of a meteorite hit Chelyabinsk, Russia on 2/15/2013 <a href="http://www.reuters.com/article/2013/02/15/us-russia-meteorite-idUSBRE91E05Z20130215">injuring over 500</a>. Learn about <a href="http://www.windows2universe.org/our_solar_system/meteors/meteors.html">meteors and meteorites</a>.<p><small><em>NASA/JPL-CalTech</em></small></p>Neptune's <a href="/neptune/lower_atmosphere.html&edu=elem&dev=1/windows.html">atmosphere</a> shows a striped pattern of <a href="/neptune/atmosphere/N_clouds_overview.html&edu=elem&dev=1/windows.html">clouds</a>. This cloud pattern is very similar to that of <a href="/jupiter/jupiter.html&edu=elem&dev=1/windows.html">Jupiter</a> and <a href="/saturn/saturn.html&edu=elem&dev=1/windows.html">Saturn</a>. Neptune even has a <a href="/neptune/atmosphere/N_clouds_GDS.html&edu=elem&dev=1/windows.html">Great Dark Spot</a> similar to Jupiter's <a href="/jupiter/atmosphere/J_clouds_GRS.html&edu=elem&dev=1/windows.html">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&dev=1/windows.html">ozone layer on Earth</a>, in the <a href="/physical_science/chemistry/methane.html&edu=elem&dev=1/windows.html">methane</a> cloud deck of Neptune.<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=elem&dev=1/windows.html">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&dev=1/windows.html">MESSENGER</a>, it shows numerous craters across the <a href="/mercury/Interior_Surface/Surface/surface_overview.html&edu=elem&dev=1/windows.html">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>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&dev=1/windows.html">full phase</a>. Secondly, the <a href="/sun/sun.html&edu=elem&dev=1/windows.html">Sun</a>, <a href="/earth/earth.html&edu=elem&dev=1/windows.html">Earth</a> and <a href="/earth/moons_and_rings.html&edu=elem&dev=1/windows.html">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>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=elem&dev=1/windows.html">solar system</a>. The space probe is about 19 billion km from the <a href="/sun/sun.html&edu=elem&dev=1/windows.html">Sun</a>. <a href="/space_missions/voyager.html&edu=elem&dev=1/windows.html">Voyager 1 and 2</a> were launched in 1977 on a <a href="/space_missions/voyager.html&edu=elem&dev=1/windows.html">mission</a> that flew them both by <a href="/jupiter/jupiter.html&edu=elem&dev=1/windows.html">Jupiter</a> and <a href="/saturn/saturn.html&edu=elem&dev=1/windows.html">Saturn</a>, with Voyager 2 continuing to <a href="/uranus/uranus.html&edu=elem&dev=1/windows.html">Uranus</a> and <a href="/neptune/neptune.html&edu=elem&dev=1/windows.html">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=elem&dev=1/windows.html">Sun</a>.<p><small><em>Image courtesy of NASA</em></small></p>The spinning vortex of <a href="https://www.windows2universe.org/saturn/saturn.html">Saturn</a>'s north polar storm resembles a giant deep red rose surrounded by green foliage in this false-color <a href="http://www.nasa.gov/mission_pages/cassini/multimedia/pia14944.html">image</a> from NASA's <a href="https://www.windows2universe.org/missions/cassini.html">Cassini spacecraft</a>. The eye is 2,000 kilometers across with cloud speeds as fast as 150 meters per second. It is not known how long this newly discovered north-polar <a href="https://www.windows2universe.org/earth/Atmosphere/hurricane/hurricane.html">hurricane</a> has been active. The view was acquired at a distance of approximately 419,000 kilometers from Saturn.<p><small><em>NASA/JPL-Caltech/SSI</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 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

Historical Events

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Did you know?

Did you know that comets have two tails, not one?

Do you know Kepler’s three laws of planetary motion?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Lithosphere
xLithosphere : The lithosphere is the outer solid part of the earth, including the crust and uppermost mantle.

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Research Highlights

Scientists Study "Glaciovolcanoes," Mountains of Fire and Ice

In the spring of 2010, the eruption of a volcano called Eyjafjallajökull in Iceland cancelled many flights in Europe. Eyjafjallajökull is a glaciovolcano, which means it's a volcano that is covered by...Read more


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