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&dev=1">atmosphere</a> shows
a striped pattern of
<a href="/neptune/atmosphere/N_clouds_overview.html&edu=high&dev=1">clouds</a>.
This cloud pattern is very similar to that of
<a href="/jupiter/jupiter.html&edu=high&dev=1">Jupiter</a> and
<a href="/saturn/saturn.html&edu=high&dev=1">Saturn</a>.
Neptune even has a <a href="/neptune/atmosphere/N_clouds_GDS.html&edu=high&dev=1">Great Dark
Spot</a> similar
to Jupiter's <a href="/jupiter/atmosphere/J_clouds_GRS.html&edu=high&dev=1">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&dev=1">ozone layer on
Earth</a>,
in the <a href="/physical_science/chemistry/methane.html&edu=high&dev=1">methane</a> cloud
deck of Neptune.<p><small><em>Image courtesy of NASA</em></small></p><a href="/asteroids/asteroid_lutetia.html&edu=high&dev=1">Lutetia</a> is a medium-sized <a href="/our_solar_system/asteroids.html&edu=high&dev=1">asteroid</a>. It orbits the <a href="/sun/sun.html&edu=high&dev=1">Sun</a> in the main asteroid belt between the planets <a href="/mars/mars.html&edu=high&dev=1">Mars</a> and <a href="/jupiter/jupiter.html&edu=high&dev=1">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=high&dev=1">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>Have you ever seen the <a href="/earth/Magnetosphere/aurora.html&edu=high&dev=1">Southern or Northern Lights</a>? Earth isn't the only planet that puts on these beautiful light shows, which are also called the "<a href="/earth/Magnetosphere/aurora.html&edu=high&dev=1">aurora</a>". Aurora have been seen at both <a href="/saturn/saturn_polar_regions.html&edu=high&dev=1">poles of Saturn</a>, too, as well as at the poles of <a href="/jupiter/magnetosphere/jupiter_aurora.html&edu=high&dev=1">Jupiter</a>.  These "<a href="/earth/Magnetosphere/tour/tour_earth_magnetosphere_09.html&edu=high&dev=1">curtains of light</a>" sometimes rise 1,200 miles (2,000 km) above the <a href="/saturn/atmosphere/S_clouds_overview.html&edu=high&dev=1">cloud tops</a> near Saturn's poles. The <a href="/space_missions/HST.html&edu=high&dev=1">Hubble Space Telescope</a> took this picture in 2004.<p><small><em>Image courtesy of NASA, ESA, J. Clarke (Boston University), and Z. Levay (STScI)</em></small></p>This historic image is the first ever taken from a spacecraft in orbit about <a href="/mercury/mercury.html&edu=high&dev=1">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&dev=1">MESSENGER</a>, it shows numerous craters across the <a href="/mercury/Interior_Surface/Surface/surface_overview.html&edu=high&dev=1">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=high&dev=1">full phase</a>. Secondly, the <a href="/sun/sun.html&edu=high&dev=1">Sun</a>, <a href="/earth/earth.html&edu=high&dev=1">Earth</a> and <a href="/earth/moons_and_rings.html&edu=high&dev=1">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=high&dev=1">solar system</a>. The space probe is about 19 billion km from the <a href="/sun/sun.html&edu=high&dev=1">Sun</a>.  <a href="/space_missions/voyager.html&edu=high&dev=1">Voyager 1 and 2</a> were launched in 1977 on a <a href="/space_missions/voyager.html&edu=high&dev=1">mission</a> that flew them both by <a href="/jupiter/jupiter.html&edu=high&dev=1">Jupiter</a> and <a href="/saturn/saturn.html&edu=high&dev=1">Saturn</a>, with Voyager 2 continuing to <a href="/uranus/uranus.html&edu=high&dev=1">Uranus</a> and <a href="/neptune/neptune.html&edu=high&dev=1">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&dev=1">Sun</a>.<p><small><em>Image courtesy of NASA</em></small></p>

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