Scientists are concerned that melting Arctic sea ice will increase the amount of fresh water in the <a href="/earth/polar/arctic_currents.html&dev=1">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&dev=1">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>There are over 900 <a href="/the_universe/uts/megalith.html&dev=1">rings of stone</a> located in the British Isles. The most famous of these stone rings is of course, <a href="/the_universe/uts/stonehenge.html&dev=1">Stonehenge</a>.    The stones of Stonehenge were put in place between 3,000 B.C and 2,000 B.C. by neolithic people.Some speculate that the site was built as a temple of worship of the ancient Earth deities. Some say it was used as an <a href="/the_universe/uts/stonehenge_astro.html&dev=1">astronomical observatory</a> of sorts. Still others say it was a burial ground.<p><small><em>  Image courtesy of Corel Photography.</em></small></p>The massive 9.0 magnitude <a href="/earth/geology/quake_1.html&dev=1">earthquake</a> off of Honshu, Japan on <a href="/headline_universe/march112011earthquaketsunami.html&dev=1">11 March 2011</a> generated a <a href="/earth/tsunami1.html&dev=1">tsunami</a> that exceeded 10 meters on the coast near the epicenter.  This image shows model projections for the tsunami wave height in cm which are in good agreement with the observed waves. Our thoughts and prayers are with those who were lost, and their families, as we remember this event.<p><small><em><a href="http://blogs.agu.org/wildwildscience/files/2011/03/680_20110311-TsunamiWaveHeight.jpg">NOAA Tsunami Wave Height Projections image</a></em></small></p>March 2012 marks the first anniversary of the 9.0 magnitude <a href="/earth/geology/quake_1.html&dev=1">earthquake</a>, <a href="/earth/tsunami1.html&dev=1">tsunami</a>, and resulting nuclear accident in Japan on <a href="/headline_universe/march112011earthquaketsunami.html&dev=1">11 March 2011</a>.  The tsunami did massive damage, wiping out entire villages and killing ~16,000 people, and leading to one of the most serious nuclear accidents in history.  This image shows before and after photos of the area north of Sendai, where 10,000 people were lost.<p><small><em>Photos by <a href="http://www.nytimes.com/interactive/2011/03/13/world/asia/satellite-photos-japan-before-and-after-tsunami.html?hp">GeoEye/EyeQ</a>.</em></small></p>Anti-crepuscular rays are beams of sunlight that appear to converge on a point opposite the sun. They are similar to crepuscular rays, but are seen opposite the sun in the sky. Anti-crepuscular rays are most frequently visible near sunrise or sunset. This photo of anti-crepuscular rays was taken at sunset in Boulder, Colorado. Crepuscular rays are usually much brighter than anti-crepuscular rays.<p><small><em> Image Courtesy of Carlye Calvin</em></small></p>This historic image is the first ever taken from a spacecraft in orbit about <a href="/mercury/mercury.html&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&dev=1">MESSENGER</a>, it shows numerous craters across the <a href="/mercury/Interior_Surface/Surface/surface_overview.html&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>

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