Scientist-astronaut Edward G. Gibson has just exited the Skylab extravehicular activity hatchway. Astronaut Gerald P. Carr, Skylab 4 commander, took this picture during the final Skylab spacewalk that took place on Feb. 3, 1974. Carr was above on the Apollo Telescope Mount when he shot this frame of Gibson. NASA
An undated artist impression shows combining observations done with ESO's Very Large Telescope and NASA's Chandra X-ray telescope of a black hole dissecting a star. Astronomy Observatory Southern European were able to make visible the flow of matter concentrate, known as jet, reported the agency in Garching, Germany, on July 7. ESO/HO/Newscom
This bootprint marks one of the first steps human beings took on the Moon in July 1969. It was made by American astronaut Buzz Aldrin during the Apollo 11 mission. NASA
Saturn's moon Rhea is partly hidden behind Saturn's rings. In April, the robotic Cassini spacecraft now orbiting Saturn took this narrow-angle view looking across the Solar System's most famous rings. NASA
This Skylab-4 onboard photograph depicts Astronaut Gerald Carr testing Astronaut Maneuvering Equipment by flying it around under weightless conditions in the Orbital Workshop. NASA
A false-color satellite image of deforestation in Rondonia State, Brazil is seen in 2000. Pink and brown areas are cleared land, tropical rainforest shows as bright red. NASA/South America Science/Newscom
This transit of the moon across the sun could not be seen from Earth. This sight was visible only from the STEREO-B spacecraft in its orbit about the sun, trailing behind the Earth in July. Newscom
Data showing the amount of outgoing heat and reflected sunlight leaving Earth on June 22, 2002 is seen. The United States is in the center. NASA/Newscom
When two galaxies collide, the stars that compose them usually do not. That's because galaxies are mostly empty space and, however bright, stars only take up only a small amount of that space. During the slow, hundred million year collision, one galaxy can still rip the other apart gravitationally, and dust and gas common to both galaxies does collide. NASA
Explanation: Frederic Church, a American landscape painter of the Hudson River School, painted what he saw in nature, and on July 20th, 1860, he saw a spectacular string of fireball meteors cross the Catskill evening sky, an extremely rare Earth-grazing meteor procession. From New York City, poet Walt Whitman also wrote of the "... strange huge meteor procession, dazzling and clear, shooting over our heads" in his poem Year of Meteors (1859-60). Frederic Church, 1860
Egypt's 'Champions of Jerusalem' group claimed responsibility for an assault on an army post last month which killed 31. The group also pledged allegiance to the leader of the Islamic State and vowed, 'this is just the beginning.'
Egypt's main terror group on Friday claimed responsibility under the name of the Islamic State for an assault against the army last month which killed 31 in the northern Sinai Peninsula.