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">solar system</a>. The space probe is about 19 billion km from the <a href="/sun/sun.html&edu=elem">Sun</a>.  <a href="/space_missions/voyager.html&edu=elem">Voyager 1 and 2</a> were launched in 1977 on a <a href="/space_missions/voyager.html&edu=elem">mission</a> that flew them both by <a href="/jupiter/jupiter.html&edu=elem">Jupiter</a> and <a href="/saturn/saturn.html&edu=elem">Saturn</a>, with Voyager 2 continuing to <a href="/uranus/uranus.html&edu=elem">Uranus</a> and <a href="/neptune/neptune.html&edu=elem">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">Sun</a>.<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">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 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>A <a href="http://iopscience.iop.org/1748-9326/8/2/024035/article">study</a> of over 40,000 written entries in Irish Annals and ice core measurements shows a strong correlation between <a href="http://www.windows2universe.org/earth/interior/eruptions.html">volcanic eruptions</a> and extreme cold weather in Ireland over a 1200 year period, from 431 to 1649.  During this time up to 48 volcanic eruptions were identified in Greenland ice core records through deposition of volcanic sulfate in annual layers of ice. Find out more about <a href="http://www.windows2universe.org/earth/climate/geosphere_volcanoes_influence_on_climate.html">volcanoes and climate</a>.<p><small><em>Image Courtesy of Marco Fulle</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>On May 20, 2013, a massive EF5 <a href="http://www.windows2universe.org/earth/Atmosphere/tornado.html">tornado</a> hit Moore, Oklahoma, devastating communities and lives.  The tornado, on the ground for 40 minutes, took a path through a subdivision of homes, destroying block after block of homes, and hitting two elementary schools just as school was ending as well as a hospital. Hundreds of people were injured, and 24 were killed.<p><small><em>Image courtesy of Ks0stm, Creative Commons Attribution-Share Alike 3.0 Unported license</em></small></p>Scientists are concerned that melting Arctic sea ice will increase the amount of fresh water in the <a href="/earth/polar/arctic_currents.html&edu=elem">Beaufort Gyre</a>, which could spill out into the Atlantic and cause major climate shifts in North America and Western Europe. Watch the <a href="/earth/changing_planet/freshwater_arctic.html&edu=elem">Changing Planet: Fresh Water in the Arctic video</a>.<p><small><em> Courtesy of Jack Cook, WHOI (<a href="http://www.whoi.edu">Woods Hole Oceanographic Institute</a>)</em></small></p>

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