German astronaut Alexander Gerst shaves the head of American astronaut Steve Swanson as they follow through on a World Cup bet aboard the International Space Station on June 26. Swanson and Flight Engineer Reid Wiseman of NASA made good on their bet with their German crewmate, shaving their heads to match Gerst's bald pate in the wake of the U.S. soccer team's loss to Germany 1-0 in the World Cup.
Brazil's Sao Simao Reservoir bursts with color in this image photographed on June 11 by an Expedition 16 crewmember on the International Space Station. This patchwork image marked a milestone of 300,000 images of Earth downlinked from the space station.
An officer of Malaysia's Islamic authority, center, uses a telescope to scan the horizon for the crescent moon that will determine the beginning of the holy fasting month of Ramadan in Jakarta, Indonesia, on June 27.
The Perseus Cluster is shown in this picture provided by NASA on June 24 and taken by the Chandra X-ray Observatory. The Perseus Cluster is one of the most massive objects in the universe, containing thousands of galaxies immersed in an enormous cloud of superheated gas.
European Space Agency astronaut Alexander Gerst enjoys the view of Earth from the windows in the cupola of the International Space Station in this image released on June 13.
Clouds cast long shadows over the South Pacific in this image photographed by an Expedition 40 crew member on the International Space Station on June 3.
A crescent moon appears over the Earth's horizon in this nighttime image photographed by an Expedition 40 crew member on the International Space Station on May 30.
Brazil, the site of the 2014 World Cup soccer matches, is seen from the International Space Station on June 12. Sao Paulo is the large cluster of night lights near the coast on the right side of the frame. Rio de Janeiro is the coastal city to the left of Sao Paulo. Belo Horizonte is the cluster of lights near frame center.
NASA's Mars Curiosity rover used the camera at the end of its arm in April and May to take dozens of component images combined into this self-portrait where the rover drilled into a sandstone target called "Windjana." The selfie was released on June 23, a day before the "Marsiversary" of the robot's landing on Mars. By Earth's reckoning, that landing happened almost two years ago — 687 days, which equals one Martian year.
A stream of plasma bursts out from the sun on May 27. Since it lacked enough force to break away, most of it fell back into the sun. This eruption was minor. NASA says such events occur almost every day on the sun and are indicative of the kind of dynamic activity being driven by powerful magnetic forces near the sun's surface. Image released on June 16.
A Hubble Space Telescope image released June 6 shows NGC 1566, a galaxy located 40 million light years away in the constellation of Dorado (The Dolphinfish). The small but extremely bright nucleus of NGC 1566 is clearly visible in this image, a telltale sign of its membership of the Seyfert class of galaxies. The centers of such galaxies are very active and luminous, emitting strong bursts of radiation and potentially harboring supermassive black holes that are many millions of times the mass of the sun.
The sun sets behind buildings on May 30 during Manhattanhenge, a semiannual occurrence in which the setting sun aligns with the street grid of New York City.
• See last month's space slideshow