A Chameleon Sky
The sands of time are running out for the central star of this the Hourglass Nebula. With its nuclear fuel exhausted, this brief, spectacular, closing phase of a sun-like star’s life occurs as its outer layers are ejected and its core becomes a cooling, fading white dwarf. In 1995, astronomers used the Hubble Space Telescope to make a series of images of planetary nebulae, including the one above. Here, delicate rings of colorful glowing gas (nitrogen-red, hydrogen-green, and oxygen-blue) outline the tenuous walls of the ‘hourglass.’ The unprecedented sharpness of Hubble’s images revealed surprising details of the nebula ejection process and may resolve the outstanding mystery of the variety of complex shapes and symmetries of planetary nebulae. Image Credit: NASA, WFPC2, HST, R. Sahai and J. Trauger (JPL)
Orbital Sunrise
The Expedition 24 crew on the International Space Station photographed this image of polar mesospheric clouds illuminated by an orbital sunrise. Polar mesospheric, or noctilucent (“night shining”), clouds usually are seen at twilight, following the setting of the sun below the horizon and darkening of Earth’s surface. Occasionally the station’s orbital track becomes nearly parallel to Earth’s day/night terminator for a time, allowing the clouds to be visible to the crew at times other than the usual twilight because of the station’s altitude. This photograph shows polar mesospheric clouds illuminated by the rising, rather than setting, sun at center right. Low clouds on the horizon appear yellow and orange, while higher clouds and aerosols are illuminated a brilliant white. Polar mesospheric clouds appear as light blue ribbons extending across the top of the image. The station was located over the Greek island of Kos in the Aegean Sea (near the southwestern coastline of Turkey) when the image was taken at approximately midnight local time. The orbital complex was tracking northeastward, nearly parallel to the terminator, making it possible to observe an apparent “sunrise” located almost due north. A similar unusual alignment of the ISS orbit track, terminator position and seasonal position of Earth’s orbit around the sun allowed for this striking imagery of over the Southern Hemisphere. Image Credit: NASA
The Red Hills
Backdropped by red hills, the Development Motor-2, or DM-2, ignites during an Aug. 31, 2010, static test that was conducted by ATK Aerospace Systems in Promontory, Utah. DM-2, the largest and most powerful solid rocket motor designed for flight, is managed by the Ares Projects Office at NASA’s Marshall Space Flight Center in Huntsville, Ala. Image Credit: NASA
Three Storms
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. Image Credit: NASA/NOAA GOES Project 
ESA PR 2010-20 ESA astronaut Paolo Nespoli will travel to the International Space Station in December on a six-month mission, serving as flight engineer for Expeditions 26 and 27. This will be the third long-duration mission by a European astronaut on the Station.
ESA’s SMOS water mission has taken another step forward by demonstrating that it will lead to a better understanding of ocean circulation. Using preliminary data, scientists can clearly see how surface currents affect the ‘Amazon plume’ in the open sea.
ESA is inviting students to propose experiments to fly on sounding rockets and stratospheric balloons. The winning teams will have the opportunity to design and build an experiment for the BEXUS balloons or the REXUS rockets.