This historic image is the first ever taken from a spacecraft in orbit about <a href="/mercury/mercury.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.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=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">MESSENGER</a>, it shows numerous craters across the <a href="/mercury/Interior_Surface/Surface/surface_overview.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.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>Scientists at the University of Michigan have found that <a href="/earth/polar/cryosphere_permafrost1.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">permafrost</a> in the <a href="/earth/polar/polar_north.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Arctic</a> is extremely sensitive to sunlight. Exposure to sunlight releases carbon gases trapped in the permafrost, including <a href="/earth/climate/earth_greenhouse.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">climate-warming</a> <a href="/physical_science/chemistry/carbon_dioxide.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">carbon dioxide</a>, to the <a href="/earth/Atmosphere/overview.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">atmosphere</a> much faster than previously thought.<p><small><em>George Kling, The University of Michigan</em></small></p>Greenland's <a href="http://www.windows2universe.org/earth/polar/cryosphere_glacier1.html">ice sheet</a> saw a record <a href="http://www.windows2universe.org/headline_universe/olpa/greenland_10dec07.html">melt</a> in July 2012. Scientists studying this event have found that this melting event was triggered by an influx of unusually warm air and amplified by the presence of a blanket of thin low-level <a href="http://www.windows2universe.org/earth/Atmosphere/cloud.html">clouds</a> which pushed temperatures up above freezing. For more information see the <a href="http://www.news.wisc.edu/21638">press release</a> from the University of Wisconsin Madison.<p><small><em>Image courtesy of University of Wisconsin-Madison</em></small></p>The <a href="http://www.windows2universe.org/earth/Atmosphere/tornado/fujita.html">EF-5</a> <a href="http://www.windows2universe.org/earth/Atmosphere/tornado.html">tornado</a> that hit El Reno, Oklahoma on May 31st, 2013 was the widest ever recorded in the US, according to the National Weather Service in Norman Oklahoma. The tornado, which remained on the ground for 40 minutes and reached 2.6 miles across (4.2 km), took the lives of 18 people including storm chasers Tim Samaras, Paul Samaras and Carl Young.<p><small><em>Image courtesy of National Weather Service, Norman Oklahoma</em></small></p>Stars don't last forever. Occasionally, a star bigger than our Sun will end its life in a huge explosion, called a <a href="/the_universe/supernova.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">supernova</a>. The center of the star collapses in less than a second, blowing away the outer layers of the star. There are many beautiful images of supernova remnants, the expanding shell of gas made up of the outer layers of the original star. This image is the Vela Supernova Remnant.<p><small><em>Image courtesy of the Anglo-Australian Observatory/Royal Observatory Edinburgh</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/earth/Atmosphere/moons/ozone_tropo.html">solar system</a>. The space probe is about 19 billion km from the <a href="/sun/sun.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Sun</a>. <a href="/space_missions/voyager.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Voyager 1 and 2</a> were launched in 1977 on a <a href="/space_missions/voyager.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">mission</a> that flew them both by <a href="/jupiter/jupiter.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Jupiter</a> and <a href="/saturn/saturn.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Saturn</a>, with Voyager 2 continuing to <a href="/uranus/uranus.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Uranus</a> and <a href="/neptune/neptune.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.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=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Sun</a>.<p><small><em>Image courtesy of NASA</em></small></p>


Attention Educator Member Teachers! Go to our special offers page for information about attractive upcoming professional development events next year. Not an Educator Member? Join Today!
Check out resources from our Affiliates!

Global locations of visitors using this page right now

Welcome to Windows to the Universe - your portal to discovery! Explore the wealth of information available here to learn about the Earth and Space sciences and related topics in the humanities including mythology, art, poetry, and more.

Our mobile website version is available now on your phone's web browser and give us feedback.

NEW Subscription Opportunities for Educators and their Students! - Classroom, School, and District Subscription Options.

Windows to the Universe Professional Development - On-site, in your school - find out more about this opportunity here. Information about our upcoming workshops and events is available on our Teacher Resources/Workshops page.

Mysterious Clouds Produced by Aircraft

Without meaning to, airplanes can cause certain types of clouds to produce snow or rain and can leave behind odd-shaped holes or channels in the clouds ...Read more
Brought to you by NSF

Video: Beaufort Scale of Wind Speeds

Did you know that our system of wind speed measurement has roots in seafaring history? Understanding wind speed was critical for sailors. Check out this video from the Little Shop of Physics ...Read more
Brought to you by CMMAP

The Sun Today

Live and recent images of the Sun from telescopes around the world and satellites in space. Spanning the spectrum from X-rays to infrared images, these views reveal sunspots, solar flares, and ...Read more
Brought to you by CISM

Happenings During the Paleozoic Era

The Cambrian period, at the beginning of the Paleozoic, was the first time that multicellular life forms flourished on Earth. By the end of the Paleozoic, and beginning of the Mesozoic, all the continents ...Read more

Mythology of Planets and the Solar System

The planets in our Solar System bear names from ancient myths. Wandering lights in the night sky have carried the names of gods from many cultures ...Read more

Historical Events

Full Earth and Space Science    History Calendar (Members only)

Teacher Opportunities

Full Teacher Events Calendar (Educator Members only)

Buried Treasure!

Space Junk

There are several thousand trackable objects in near-Earth space. These objects are baseball size or...Read more


Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA