This is a Space Shuttle mission STS-61 onboard view showing astronauts Story Musgrave and Jeffrey Hoffman preforming repairs to the Hubble Space Telescope during their Extra Vehicular Activity. Astronauts' work was made easier by the HST's many crew aids. Astronaut Musgrave makes use of one of the spacecraft's handholds. Launched on December 1, 1993, the Space Shuttle Orbiter Endeavor STS-061 mission was the 59th Shuttle flight. NASA
In a splendid portrait created by light and gravity, Saturn's lonely moon Mimas is seen against the cool, blue-streaked backdrop of Saturn's northern hemisphere. Delicate shadows cast by the rings arc gracefully across the planet, fading into darkness on Saturn's night side. The part of the atmosphere seen here appears darker and more bluish than the warm brown and gold hues seen in Cassini images of the southern hemisphere, due to preferential scattering of blue wavelengths by the cloud-free upper atmosphere. NASA/JPL/Space Science Institute
Ultraviolet image of the planetary nebula NGC 7293 also known as the Helix Nebula. It is the nearest example of what happens to a star, like our own Sun, as it approaches the end of its life when it runs out of fuel, expels gas outward and evolves into a much hotter, smaller and denser white dwarf star. NASA/JPL-Caltech/SSC
A close-up view of a star racing through space faster than a speeding bullet can be seen in this image from NASA's Galaxy Evolution Explorer. The star, called Mira, is traveling at 291,000 miles per hour. As it hurls along, it sheds material that will be recycled into new stars, planets and possibly even life. In this image, Mira is moving from left to right. NASA/JPL-Caltech
This artist's concept illustrates how planetary systems arise out of massive collisions between rocky bodies. New findings from NASA's Spitzer Space Telescope show that these catastrophes continue to occur around stars even after they have developed full-sized planets, when they are as old as one hundred million years. For reference, our own Sun, at 4.5 billion years old, is far past this late stage of planet formation. NASA/JPL-Caltech
Astronaut Edwin E. Aldrin, Jr., Lunar Module LM pilot, unpacks the Early Apollo Scientific Experiments Package EASEP from the Modularized Equipment Storage Assembly MESA of the LM. Image taken at Tranquility Base during the Apollo 11 Mission. NASA
The current Geostationary Operational Environmental Satellite GOES-13 captured this image of Hurricane Danielle heading for the north Atlantic (top center), Hurricane Earl with a visible eye hitting the Leeward Islands (left bottom) and a developing tropical depression 8 (lower right) at 1:45 p.m. EDT on Aug. 30. NASA GOES Project
This is a color map of the composition of a portion of Saturn's moon Hyperion's surface. In this map, blue shows the maximum exposure of frozen water, red denotes carbon dioxide ice ("dry ice"), magenta indicates regions of water plus carbon dioxide, yellow is a mix of carbon dioxide and an unidentified material. This map was made with data from the Visual and Infrared Mapping Spectrometer aboard the Cassini spacecraft during its flyby of Hyperion in September 2005. NASA/JPL/University of Arizona/Ames/Space Science Institute
Image of the spiral galaxy NGC 1512 revealing all wavelengths from ultraviolet to infrared. NGC 1512 lies in the southern constellation of Horologium, located 30 million light years from Earth. The galaxy spans 70,000 light years, nearly as much as the Milky Way Galaxy. NASA/Hubble
Spiral galaxy NGC 4921 presently is estimated to be 320 million light years distant. This image, taken by the Hubble Space Telescope, is being used to identify key stellar distance markers known as Cepheid variable stars. The magnificent spiral NGC 4921 has been informally dubbed anemic because of its low rate of star formation and low surface brightness. NASA, ESA, K. Cook (LLNL)
Near the outskirts of the Small Magellanic Cloud, a satellite galaxy some 200 thousand light-years distant, lies 5 million year young star cluster NGC 602. Surrounded by natal gas and dust, NGC 602 is featured in this stunning Hubble image of the region. Fantastic ridges and swept back shapes strongly suggest that energetic radiation and shock waves from NGC 602's massive young stars have eroded the dusty material and triggered a progression of star formation moving away from the cluster's center. NASA
Estimates of the number of disappeared people in Mexico during a decade of drug and gang violence rival numbers from Argentina's Dirty War and Colombia's armed conflict. New laws protecting victim's rights require the government to establish a national registry of those who have disappeared.
ByEmily Pickrell, Contributor
One of the startling unknowns in the story of Mexico’s recent wave of violence is just how many people can be counted among its disappeared.