Category: NASA

Kwanzaa Tholus on Ceres : These images show a …

Kwanzaa Tholus on Ceres : These images show a subtle feature on dwarf planet Ceres called Kwanzaa Tholus. (via NASA)

On January 28, 1986, the Space Shuttle Challen…

On January 28, 1986, the Space Shuttle Challenger and her seven-member crew were lost when a ruptured O-ring in the right Solid Rocket Booster caused an explosion soon after launch. This photograph, taken a few seconds after the accident, shows the Space Shuttle Main Engines and Solid Rocket Booster exhaust plumes entwined around a ball of gas from the External Tank. Because shuttle launches had become almost routine after fifty successful missions, those watching the shuttle launch in person and on television found the sight of the explosion especially shocking and difficult to believe until NASA confirmed the accident.

via: NASA on The Commons

Phaethon s Brood : Based on its well-measured …

Phaethon s Brood : Based on its well-measured orbit, 3200 Phaethon (sounds like FAY-eh-thon) is recognized as the source of the meteroid stream responsible for the annual Geminid meteor shower. Even though most meteor showers’ parents are comets, 3200 Phaethon is a known and closely tracked near-Earth asteroid with a 1.4 year orbital period. Rocky and sun-baked, its perihelion or closest approach to the Sun is well within the orbit of innermost planet Mercury. In this telescopic field of view, the asteroid’s rapid motion against faint background stars of the heroic constellation Perseus left a short trail during the two minute total exposure time. The parallel streaks of its meteoric children flashed much more quickly across the scene. The family portrait was recorded near the Geminid meteor shower’s very active peak on December 13. That was just before 3200 Phaethon’s historic December 16 closest approach to planet Earth. via NASA

Possible variations in chemical composition …

Possible variations in chemical composition from one part of Saturn’s ring system to another are visible in this Voyager 2 picture as subtle color variations that can be recorded with special computer-processing techniques.

Image Credit: NASA/JPL

Hubble’s Holiday Nebula “Ornament” : The…

Hubble’s Holiday Nebula “Ornament” : The Hubble Space Telescope captured what looks like a colorful holiday ornament in space. It’s actually an image of NGC 6326, a planetary nebula with glowing wisps of outpouring gas. (via NASA)

Launch Day! : On Dec. 21, 1968, the Apollo 8 c…

Launch Day! : On Dec. 21, 1968, the Apollo 8 crew leaves the Kennedy Space Center’s then-named Manned Spacecraft Operations Building during the mission’s prelaunch countdown on the way to their history-making lunar orbiting flight. (via NASA)

Hello From Above : Greetings from @Astro_Sabot…

Hello From Above : Greetings from @Astro_Sabot, otherwise known as Mark Vande Hei, from aboard the International Space Station. (via NASA)

The Bluest of Ice : Acquired on November 29 by…

The Bluest of Ice : Acquired on November 29 by Operation IceBridge during a flight to Victoria Land, this image shows an iceberg floating in Antarctica’s McMurdo Sound. (via NASA)

NASA’s Fermi Satellite Celebrates 10 Years of …

On June 11, NASA’s Fermi Gamma-ray Space Telescope celebrates a decade of using gamma rays, the highest-energy form of light in the cosmos, to study black holes, neutron stars, and other extreme cosmic objects and events.

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Left: A STEREO B image of the far side of the sun during the Sept. 1, 2014, solar eruption. Right: The Earth-facing side of the sun at the same time as seen by NASA’s Solar Dynamics Observatory. The view includes the area from which NASA’s Fermi detected high-energy gamma rays. Includes animated gif. Credit: NASA/STEREO and NASA/SDO

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A rupture in the crust of a highly magnetized neutron star, shown here in an artist’s rendering, can trigger high-energy eruptions. Fermi observations of these blasts include information on how the star’s surface twists and vibrates, providing new insights into what lies beneath. Credits: NASA’s Goddard Space Flight Center/S. Wiessinger 

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Fermi finds the first extragalactic gamma-ray pulsar. NASA’s Fermi Gamma-ray Space Telescope has detected the first extragalactic gamma-ray pulsar, PSR J0540-6919, near the Tarantula Nebula (top center) star-forming region in the Large Magellanic Cloud, a satellite galaxy that orbits our own Milky Way. Fermi detects a second pulsar (right) as well but not its pulses. PSR J0540-6919 now holds the record as the highest-luminosity gamma-ray pulsar. The angular distance between the pulsars corresponds to about half the apparent size of a full moon. Background: An image of the Tarantula Nebula and its surroundings in visible light. Credit: NASA’s Goddard Space Flight Center; background: ESO/R. Fosbury (ST-ECF)

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These maps, both centered on the north galactic pole, show how the sky looks at gamma-ray energies above 100 million electron volts (MeV). Left: The sky during a three-hour interval prior to the detection of GRB 130427A. Right: A three-hour interval starting 2.5 hours before the burst and ending 30 minutes into the event, illustrating its brightness relative to the rest of the gamma-ray sky. GRB 130427A was located in the constellation Leo near its border with Ursa Major, whose brightest stars form the familiar Big Dipper. For reference, this image includes the stars and outlines of both constellations. Labeled. Credit: NASA/DOE/Fermi LAT Collaboration.

Novae typically originate in binary systems containing sun-like stars, as shown in this artist’s rendering. A nova in a system like this likely produces gamma rays (magenta) through collisions among multiple shock waves in the rapidly expanding shell of debris. Credit: NASA’s Goddard Space Flight Center/S. Wiessinger

Gamma Rays in Active Galactic Nuclei

Gamma-ray Burst Photon Delay as Expected by Quantum Gravity. Print resolution still. In this illustration, one photon (purple) carries a million times the energy of another (yellow). Some theorists predict travel delays for higher-energy photons, which interact more strongly with the proposed frothy nature of space-time. Yet Fermi data on two photons from a gamma-ray burst fail to show this effect, eliminating some approaches to a new theory of gravity. Credit: NASA/Sonoma State University/Aurore Simonnet


“Fermi’s first 10 years have produced numerous scientific discoveries that have revolutionized our understanding of the gamma-ray universe,” said Paul Hertz, Astrophysics Division director at NASA Headquarters in Washington. 

By scanning the sky every three hours, Fermi’s main instrument, the Large Area Telescope (LAT), has observed more than 5,000 individual gamma-ray sources, including an explosion called GRB 130427A, the most powerful gamma-ray burst scientists have detected.

In 1949, Enrico Fermi — an Italian-American pioneer in high-energy physics and Nobel laureate for whom the mission was named — suggested that cosmic rays, particles traveling at nearly the speed of light, could be propelled by supernova shock waves. In 2013, Fermi’s LAT used gamma rays to prove these stellar remnants are at least one source of the speedy particles.

Fermi’s all-sky map, produced by the LAT, has revealed two massive structures extending above and below the plane of the Milky Way. These two “bubbles” span 50,000 light-years and were probably produced by the supermassive black hole at the center of the galaxy only a few million years ago.

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Seeing an X-Plane’s Sonic Boom : This sc…

Seeing an X-Plane’s Sonic Boom : This schlieren image shows an Air Force Test Pilot School T-38 in a transonic state, meaning the aircraft is transitioning from a subsonic speed to supersonic. (via NASA)