Astronomy Pictures

Making the stuff of science fiction into reality, NASA engineers are testing solar sails--a unique propulsion technology that one day could enable deep space missions. Much like the wind pushing a sailboat through water, solar sails rely on sunlight to propel vehicles through space. The sail captures constantly streaming solar particles, called photons, with giant sails built from a lightweight material. Over time, the buildup of these particles provides enough thrust for a small spacecraft to travel in space. This image is of a four-quadrant solar sail system, measuring 66 feet on each side that is being tested in the world's largest vacuum chamber at NASA's Glenn Research Center at Plum Brook Station in Sandusky, Ohio. Image Credit: NASA

Researchers do not yet know what is lighting up IRAS 05437+2502, a small, faint nebula that spans only 1/18th of a full moon toward the constellation of the Taurus. Particularly enigmatic is the bright upside-down V that defines the upper edge of this floating mountain of interstellar dust. This ghost-like nebula involves a small star-forming region filled with dark dust that was first noted in images taken by the IRAS satellite in infrared light in 1983. This recently released image from the Hubble Space Telescope shows many new details, but has not uncovered a clear cause of the bright sharp arc. Image Credit: NASA, ESA, Hubble, R. Sahai (JPL)

What could cause such rays of dark?

This infrared image taken by NASA's Wide-field Infrared Survey Explorer, or WISE, shows a star-forming cloud teeming with gas, dust and massive newborn stars. WISE, which is surveying the whole sky in infrared light, is particularly sensitive to the warm dust that permeates star-forming clouds like this one. In this way, WISE complements visible-light observations. The mission also complements Hubble and other telescopes by showing the 'big picture," providing context for more detailed observations. The cluster contains some of the most massive stars known. Winds and radiation from the stars are evaporating and dispersing the cloud material from which they formed, warming the cold dust and gas surrounding the central nebula. This greenish "halo" of warm cloud material is seen best by WISE due to its large field of view and improved sensitivity over past all-sky infrared surveys. Image Credit: NASA/JPL-Caltech/UCLA

Why do some sand dunes on Titan appear backwards?

Reflecting on his experience as he emerged from the craft into the daylight on the Expedition 24 mission's second spacewalk, astronaut Doug Wheelock said "the colors of the Earth just explode at you as you exit toward the planet. Notice what looks like scorch marks on the hatch thermal cover, the effect of vacuum and atomic oxygen on the threads and thread sealant used on the thermal cover. The 'smell' of space follows suit, I’ve heard it described like burnt cake or cookies, or like the smell of an extinguished match." Wheelock and fellow astronaut Tracy Caldwell Dyson completed the second of three spacewalks to remove a failed ammonia coolant pump module on the station's S1 truss on Wednesday, Aug. 11. Image Credit: NASA

What's lighting up nebula IRAS 05437+2502?

Two hours before closest approach to

Testing advanced designs for high-speed aircraft in 1948, an engineer makes final calibrations to a model mounted in the 6 x 6 Foot Supersonic Wind Tunnel at the NACA Ames Aeronautical Laboratory, Moffett Field, California. NACA, NASA’s predecessor organization the National Advisory Committee for Aeronautics, was established in March 1913 by Congress to "supervise and direct the scientific study of the problems of flight, with a view to their practical solutions." The Ames Aeronautical Laboratory is now NASA’s Ames Research Center. Image Credit: NASA

The idea behind a communications satellite is simple: send a signal into space, and send it back down to another spot on the globe. In NASA's early days, engineers discovered the easiest way to accomplish this: bounce signals off a giant metal balloon floating in orbit. The concept was developed into the aptly-named Echo program, and Echo 1A became the first successful launch of the project on Aug. 12, 1960. Echo 1A, now commonly known as just Echo I, was a 100 foot diameter balloon made of mylar polyester. The spacecraft was designed as a passive communications reflector for transcontinental and intercontinental telephone, radio, and television signals. Pictured here is a scale prototype of the Echo satellite undergoing a Skin Stress Test on May 1, 1960. The prototype was 12 feet in diameter, with the size being chosen because that was the ceiling height in the NASA Langley model shop. After an unsuccessful launch attempt for the original Echo I satellite, Echo 1A and the follow-on Echo II were successfully launched. The Echo projects were instrumental in letting the world see that the U.S. was a major force in the space race not very far behind Russia. Among the many contributions of the Echo programs are the first voice communication via satellite which was made by none other than then President Eisenhower and the first coast-to-coast telephone call using a satellite. In addition, the Echo programs resulted in advances in atmospheric density, solar pressure, gossamer structures, solar sailing, and transmitting videos via satellites. The Echo 1A satellite re-entered the atmosphere on May 24, 1968. Image Credit: NASA

The Centaur Standard Shroud at Glenn Research Center's Space Power Facility, Plum Brook Station, protects spacecraft during launch. When it was constructed, the Space Power Facility was the world's largest vacuum chamber. It stands more than 122 feet high, 100 feet in diameter and provides a vacuum environment for the study of space propulsion. Originally commissioned for nuclear-electric propulsion studies, the SPF has been recommissioned for current and future use in the ongoing research and development of space propulsion systems. Image Credit: NASA

A long-exposure Hubble Space Telescope image shows a majestic face-on spiral galaxy located deep within the Coma Cluster of galaxies, which lies 320 million light- years away in the northern constellation Coma Berenices. The galaxy, known as NGC 4911, contains rich lanes of dust and gas near its center. These are silhouetted against glowing newborn star clusters and iridescent pink clouds of hydrogen, the existence of which indicates ongoing star formation. Hubble has also captured the outer spiral arms of NGC 4911, along with thousands of other galaxies of varying sizes. The high resolution of Hubble's cameras, paired with considerably long exposures, made it possible to observe these faint details. This natural-color Hubble image, which combines data obtained in 2006, 2007, and 2009 from the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys, required 28 hours of exposure time. Image Credit: NASA/ESA/Hubble Heritage Team (STScI/AURA)

Sometimes, during a

What planet is this?

Astronaut Leland Melvin waved to the crowds from the NASA Glenn Research Center float during the 2010 Pro Football Hall of Fame Festival Timken Grand Parade on Saturday, August 7, 2010. Melvin is a veteran of two space shuttle flights to the International Space Station and has logged over 565 hours in space. Prior to his selection as an astronaut, he was chosen by the Detroit Lions in the eleventh round of the 1986 National Football League college draft and participated in the Toronto Argonauts and Dallas Cowboys football training camps. Melvin is currently on assignment at NASA Headquarters in Washington, D.C., in support of the Summer of Innovation program. In doing so, he has traveled across the country, engaging thousands of students and teachers in the excitement of space exploration and inspiring them to pursue careers in science, technology, engineering and mathematics, or STEM. The Summer of Innovation initiative is a multi-faceted, intensive middle school program designed to improve STEM teaching and learning in partnership with federal agencies, non profits, industry, and academic and information organizations. Melvin rode on the NASA Glenn Research Center float that depicted the Space Shuttle Discovery. The float won the Janice C. Meyer award for exceptional merit during the parade. Image Credit: NASA/Chris Lynch