One of the more spectacular scenes of the aurora australis was photographed by one of the Expedition 40 crew members aboard the International Space Station from an altitude of approximately 223 nautical miles
July 11, 2014
This view, captured by the NASA/ESA Hubble Space Telescope, shows a nearby spiral galaxy known as NGC 1433. At about 32 million light-years from Earth, it is a type of very active galaxy known as a Seyfert galaxy — a classification that accounts for 10% of all galaxies. They have very bright, luminous centers that are comparable in brightness to that of our entire galaxy, the Milky Way.
Galaxy cores are of great interest to astronomers. The centers of most, if not all, galaxies are thought to contain a supermassive black hole, surrounded by a disk of in-falling material.
NGC 1433 is being studied as part of a survey of 50 nearby galaxies known as the Legacy ExtraGalactic UV Survey (LEGUS). Ultraviolet radiation is observed from galaxies, mainly tracing the most recently formed stars. In Seyfert galaxies, ultraviolet light is also thought to emanate from the accretion discs around their central black holes. Studying these galaxies in the ultraviolet part of the spectrum is incredibly useful to study how the gas is behaving near the black hole. This image was obtained using a mix of ultraviolet, visible, and infrared light.
LEGUS will study a full range of properties from a sample of galaxies, including their internal structure. This Hubble survey will provide a unique foundation for future observations with the James Webb Space Telescope (JWST) and the Atacama Large Millimeter/submillimeter Array (ALMA). ALMA has already caught unexpected results relating to the center of NGC 1433, finding a surprising spiral structure in the molecular gas close to the center of NGC 1433. The astronomers also found a jet of material flowing away from the black hole, extending for only 150 light-years — the smallest such molecular outflow ever observed in a galaxy beyond our own.
Image Credit: ESA/Hubble & NASA, Acknowledgements: D. Calzetti (UMass) and the LEGUS Team
Explanation from: http://www.nasa.gov/content/goddard/hubble-sees-a-galaxy-with-a-glowing-heart/
June 20, 2014
This storm cell photo was taken from NASA's high-altitude ER-2 aircraft on May 23, 2014, during a study aimed at gaining a better understanding of precipitation over mountainous terrain. The Integrated Precipitation and Hydrology Experiment, or IPHEx, field campaign is part of the ground validation effort for the Global Precipitation Measurement (GPM) mission, an international satellite mission led by NASA and the Japan Aerospace Exploration Agency. GPM's Core Observatory launched Feb. 27, 2014, to provide next-generation observations of rain and snow worldwide every three hours. But to get accurate measurements from space, scientists have to understand what is happening on the ground.
For the six-week IPHEx field campaign over the southern Appalachian mountains, the NASA team and their partners at Duke University and NOAA's Hydrometeorological Test Bed set up ground stations with rain gauges and ground radar throughout western North Carolina. In addition to the ground sites, they also collected data sets from satellites and two aircraft.
The NASA ER-2 aircraft that deployed to Robins Air Force Base in Warner Robins, Georgia, was able to fly when rain was in the air. The ER-2's cruising altitude of 65,000 feet kept it well above the storm systems it was observing, allowing it to act as a proxy-satellite. The aircraft carried a suite of instruments, including three that took measurements similar to those taken by GPM's Core Observatory.
Image Credit: NASA / Stu Broce
Explanation from: http://www.nasa.gov/content/storm-cell-over-the-southern-appalachian-mountains/