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Asteroid To Fly By Earth Safely On January 26
Image credit: NASA/JPL-Caltech
An asteroid, designated 2004 BL86, will safely pass about three times the distance of Earth to the moon on January 26. From its reflected brightness, astronomers estimate that the asteroid is about a third of a mile (0.5 kilometers) in size. The flyby of 2004 BL86 will be the closest by any known space rock this large until asteroid 1999 AN10 flies past Earth in 2027.
At the time of its closest approach on January 26, the asteroid will be approximately 745,000 miles (1.2 million kilometers) from Earth.
“Monday, January 26 will be the closest asteroid 2004 BL86 will get to Earth for at least the next 200 years,” said Don Yeomans, who is retiring as manager of NASA’s Near Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California, after 16 years in the position. “And while it poses no threat to Earth for the foreseeable future, it’s a relatively close approach by a relatively large asteroid, so it provides us a unique opportunity to observe and learn more.”
NASA’s Airborne Observatory Begins 2015 Science Campaign
Credit: NASA/USRA/Greg Perryman
The Stratospheric Observatory for Infrared Astronomy, or SOFIA, Program began its third season of science flights on Jan. 13, 2015. SOFIA is NASA’s next generation flying observatory and is fitted with a 2.5-meter (100-inch) diameter telescope that studies the universe at infrared wavelengths.
“Last night’s flight used the German Receiver for Astronomy at Terahertz Frequencies (GREAT) spectrometer to study the chemical composition and motions of gas in a star-forming region, a young star, and a supernova remnant,” said Pamela Marcum, NASA’s SOFIA project scientist. “Observing at infrared wavelengths enables us to see through interstellar dust to record the spectral signatures of molecules in these regions. From this we can study the abundances of molecules and their formation process.”
Water vapor in the Earth’s atmosphere absorbs infrared radiation, preventing a large section of the infrared spectrum from reaching ground-based observatories. SOFIA is a heavily modified Boeing 747 Special Performance jetliner that flies at altitudes between 39,000 to 45,000 feet (12 to 14 km), above more than 99 percent of Earth’s atmospheric water vapor giving astronomers the ability to study celestial objects at wavelengths that cannot be seen from ground-based observatories.
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Artificial Intelligence Helps Stanford Physicists Predict Dangerous Solar Flares
Credit: NASA/SDO and the AIA; EVE; and HMI science teams
Solar flares can release the energy equivalent of many atomic bombs, enough to cut out satellite communications and damage power grids on Earth, 93 million miles away. The flares arise from twisted magnetic fields that occur all over the sun’s surface, and they increase in frequency every 11 years, a cycle that is now at its maximum.
Using artificial intelligence techniques, Stanford solar physicists Monica Bobra and Sebastien Couvidat have automated the analysis of the largest ever set of solar observations to forecast solar flares using data from the Solar Dynamics Observatory (SDO), which takes more data than any other satellite in NASA history. Their study identifies which features are most useful for predicting solar flares.
The Gemini Planet Imager Produces Stunning Observations In Its First Year
Image credit: Christian Marois (NRC Canada), Patrick Ingraham (Stanford University) and the GPI Team
Stunning exoplanet images and spectra from the first year of science operations with the Gemini Planet Imager (GPI) were featured today in a press conference at the 225th meeting of the American Astronomical Society (AAS) in Seattle, Washington. The Gemini Planet Imager GPI is an advanced instrument designed to observe the environments close to bright stars to detect and study Jupiter-like exoplanets (planets around other stars) and see protostellar material (disk, rings) that might be lurking next to the star.
Marshall Perrin (Space Telescope Science Institute), one of the instrument’s team leaders, presented a pair of recent and promising results at the press conference. He revealed some of the most detailed images and spectra ever of the multiple planet system HR 8799. His presentation also included never-seen details in the dusty ring of the young star HR 4796A. “GPI’s advanced imaging capabilities have delivered exquisite images and data,” said Perrin. “These improved views are helping us piece together what’s going on around these stars, yet also posing many new questions.”
A New, Public View Of The Sky
Photo: Adam Block and Vic Eden/Mount Lemmon SkyCenter/UA
For the first time, scientists and the public are beginning to see the large-scale structure of the universe, thanks to the Sloan Digital Sky Survey. UA scientists provide scientific expertise and crucial technology to the largest project ever undertaken to map the cosmos.
On Jan. 6, the Sloan Digital Sky Survey issued its latest public data release, the final release of the third epoch of the survey. Weighing in at more than 100 Terabytes, “Data Release 12” (DR12) contains measurements of the properties of nearly half a billion stars and galaxies, making it one of the largest and richest databases in the history of astronomy.
“The most astonishing feature of the SDSS is the breadth of ground-breaking research it enables,” said Daniel Eisenstein of the Harvard-Smithsonian Center for Astrophysics, the director of SDSS-III. Eisenstein started the survey during his tenure as a professor at the UA’s Steward Observatory, one of the survey’s partner institutions.
Unusual Light Signal Yields Clues About Elusive Black Hole Merger
Credit: Santiago Lombeyda/Caltech Center for Data-Driven Discovery
The central regions of many glittering galaxies, our own Milky Way included, harbor cores of impenetrable darkness—black holes with masses equivalent to millions, or even billions, of suns. What is more, these supermassive black holes and their host galaxies appear to develop together, or “co-evolve.” Theory predicts that as galaxies collide and merge, growing ever more massive, so too do their dark hearts.
Black holes by themselves are impossible to see, but their gravity can pull in surrounding gas to form a swirling band of material called an accretion disk. The spinning particles are accelerated to tremendous speeds and release vast amounts of energy in the form of heat and powerful X-rays and gamma rays. When this process happens to a supermassive black hole, the result is a quasar—an extremely luminous object that outshines all of the stars in its host galaxy and that is visible from across the universe. “Quasars are valuable probes of the evolution of galaxies and their central black holes,” says George Djorgovski, professor of astronomy and director of the Center for Data-Driven Discovery at Caltech.
NASA Observatories Take An Unprecedented Look Into Superstar Eta Carinae
Image Credit:
NASA, ESA, and the Hubble SM4 ERO Team
Eta Carinae, the most luminous and massive stellar system within 10,000 light-years of Earth, is known for its surprising behavior, erupting twice in the 19th century for reasons scientists still don’t understand. A long-term study led by astronomers at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, used NASA satellites, ground-based telescopes and theoretical modeling to produce the most comprehensive picture of Eta Carinae to date. New findings include Hubble Space Telescope images that show decade-old shells of ionized gas racing away from the largest star at a million miles an hour, and new 3-D models that reveal never-before-seen features of the stars’ interactions.
“We are coming to understand the present state and complex environment of this remarkable object, but we have a long way to go to explain Eta Carinae’s past eruptions or to predict its future behavior,” said Goddard astrophysicist Ted Gull, who coordinates a research group that has monitored the star for more than a decade.
Galactic Herding: New Image Brings Galaxy Diversity To Life
Image credit: Gemini Observatory/AURA
Galaxy groups are the most evident structures in the nearby universe. They are important laboratories for studying how galaxies form and evolve beyond our own Local Group of galaxies, which includes the Milky Way and the Great Spiral in Andromeda. Exploring the nature of these extragalactic “herds” may help to unlock the secrets to the overall structure of the universe.
Unlike animal herds, which are generally the same species traveling together, most galaxies move through space in associations comprised of myriad types, shapes, and sizes. Galaxy groups differ in their richness, size, and internal structure as well as the ages of their members. Some group galaxies are composed mainly of ancient stars, while others radiate with the power and splendor of youth.
These facts raise important questions for astronomers: Do all the galaxies in a group share a common origin? Are some just chance alignments? Or do galaxy groups pick up “strays” along the way and amalgamate them into the group?
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