Thursday, February 2, 2012

Remnant of an Explosion With a Powerful Kick?

Remnant Explosion

Vital clues about the devastating ends to the lives of massive stars can be found by studying the aftermath of their explosions. In its more than twelve years of science operations, NASA's Chandra X-ray Observatory has studied many of these supernova remnants sprinkled across the Galaxy. The latest example of this important investigation is Chandra's new image of the supernova remnant known as G350.1+0.3. This stellar debris field is located some 14,700 light years from the Earth toward the center of the Milky Way.

Evidence from Chandra and from ESA's XMM-Newton telescope suggest that a compact object within G350.1+0.3 may be the dense core of the star that exploded. The position of this likely neutron star, seen by the arrow pointing to "neutron star" in the inset image, is well away from the center of the X-ray emission. If the supernova explosion occurred near the center of the X-ray emission then the neutron star must have received a powerful kick in the supernova explosion.

Data from Chandra and other telescopes suggest this supernova remnant, as it appears in the image, is between 600 and 1,200 years old. If the estimated location of the explosion is correct, this means that the neutron star has been moving at a speed of at least 3 million miles per hour since the explosion This is comparable to the exceptionally high speed derived for the neutron star in Puppis A, another neutron star moving at a blistering pace within a supernova remnant. The G350+1+0.3 data provide new evidence that extremely powerful "kicks" may be imparted to neutron stars left behind once the supernova has exploded.

Tuesday, January 31, 2012

Earth's Energy Budget Remained Out of Balance despite Unusually Low Solar Activity

Low Solar Activity

A new NASA study underscores the fact that greenhouse gases generated by human activity -- not changes in solar activity are the primary force driving global warming. The study offers an updated calculation of the Earth's energy imbalance, the difference between the amount of solar energy absorbed by Earth's surface and the amount returned to space as heat. The researchers' calculations show that, despite unusually low solar activity between 2005 and 2010, the planet continued to absorb more energy than it returned to space.

James Hansen, director of NASA's Goddard Institute for Space Studies (GISS) in New York City, led the research. Atmospheric Chemistry and Physics published the study last December. Total solar irradiance, the amount of energy produced by the sun that reaches the top of each square meter of the Earth's atmosphere, typically declines by about a tenth of a percent during cyclical lulls in solar activity caused by shifts in the sun's magnetic field. Usually solar minimums occur about every eleven years and last a year or so, but the most recent minimum persisted more than two years longer than normal, making it the longest minimum recorded during the satellite era.

Pinpointing the magnitude of Earth's energy imbalance is fundamental to climate science because it offers a direct measure of the state of the climate. Energy imbalance calculations also serve as the foundation for projections of future climate change. If the imbalance is positive and more energy enters the system than exits, Earth grows warmer. If the imbalance is negative, the planet grows cooler.

Saturday, January 28, 2012

New Ideas Sharpen Focus for Greener Aircraft

Greener Aircraft

Leaner, greener flying machines for the year 2025 are on the drawing boards of three industry teams under contract to the NASA Aeronautics Research Mission Directorate's Environmentally Responsible Aviation Project.

Teams from The Boeing Company in Huntington Beach, Calif., Lockheed Martin in Palmdale, Calif., and Northrop Grumman in El Segundo, Calif., have spent the last year studying how to meet NASA goals to develop technology that would allow future aircraft to burn 50 percent less fuel than aircraft that entered service in 1998 (the baseline for the study), with 75 percent fewer harmful emissions; and to shrink the size of geographic areas affected by objectionable airport noise by 83 percent.

"The real challenge is we want to accomplish all these things simultaneously," said ERA project manager Fay Collier. "It's never been done before. We looked at some very difficult metrics and tried to push all those metrics down at the same time."

Friday, January 27, 2012

NASA's J-2X Engine Kicks Off 2012 With Powerpack Testing

J-2X Engine

A new series of tests on the engine that will help carry humans to deep space will begin next week at NASA's Stennis Space Center in southern Mississippi. The tests on the J-2X engine bring NASA one step closer to the first human-rated liquid oxygen and liquid hydrogen rocket engine to be developed in 40 years.

Tests will focus on the powerpack for the J-2X. This highly efficient and versatile advanced rocket engine is being designed to power the upper stage of NASA's Space Launch System, a new heavy-lift launch vehicle capable of missions beyond low-Earth orbit. The powerpack comprises components on the top portion of the engine, including the gas generator, oxygen and fuel turbopumps, and related ducts and valves that bring the propellants together to create combustion and generate thrust.

"The J-2X upper stage engine is vital to achieving the full launch capability of the heavy-lift Space Launch System," said William Gerstenmaier, NASA's associate administrator for the Human Exploration and Operations Mission Directorate. "The testing today will help insure that a key propulsion element is ready to support exploration across the solar system."

Wednesday, January 25, 2012

Construction Begins on Atlantis' Permanent Home


With space shuttle Atlantis' 25-year spaceflight career now in the history books, its next mission -- to inform and inspire generations of visitors to the Kennedy Space Center Visitor Complex in Florida -- is one step closer to reality. A groundbreaking ceremony Jan. 18 officially launched construction of a new 65,000-square-foot exhibit at the complex's Space Shuttle Plaza, where NASA's fourth space-rated orbiter will be the main attraction.

"It is an honor to create the home for space shuttle Atlantis and to work with NASA to tell its story to the world," said Jeremy Jacobs, chairman and chief executive officer of Delaware North Companies, which operates the visitor complex for NASA.

Participating in the event were Jacobs; Janet Petro, Kennedy Space Center deputy director; Chris Ferguson, who commanded Atlantis on its final mission, STS-135; Bill Moore, chief operating officer of the Kennedy Space Center Visitor Complex; and Florida Lt. Governor Jennifer Carroll. Wearing hard hats and gripping shovels, they made the ceremonial first turn of the soil at the construction site.

Monday, January 23, 2012

NASA Finds 2011 Ninth-Warmest Year on Record

Ninth-Warmest Year

The global average surface temperature in 2011 was the ninth warmest since 1880, according to NASA scientists. The finding continues a trend in which nine of the 10 warmest years in the modern meteorological record have occurred since the year 2000.

NASA's Goddard Institute for Space Studies (GISS) in New York, which monitors global surface temperatures on an ongoing basis, released an updated analysis that shows temperatures around the globe in 2011 compared to the average global temperature from the mid-20th century. The comparison shows how Earth continues to experience warmer temperatures than several decades ago. The average temperature around the globe in 2011 was 0.92 degrees F (0.51 C) warmer than the mid-20th century baseline.

"We know the planet is absorbing more energy than it is emitting," said GISS Director James E. Hansen. "So we are continuing to see a trend toward higher temperatures. Even with the cooling effects of a strong La NiƱa influence and low solar activity for the past several years, 2011 was one of the 10 warmest years on record."

Friday, January 20, 2012

Revisiting the 'Pillars of Creation'


In 1995, NASA's Hubble Space Telescope took an iconic image of the Eagle nebula, dubbed the "Pillars of Creation," highlighting its finger-like pillars where new stars are thought to be forming. Now, the Herschel Space Observatory has a new, expansive view of the region captured in longer-wavelength infrared light.The Herschel mission is led by the European Space Agency, with important NASA contributions.

The Eagle nebula is 6,500 light-years away in the constellation of Serpens. It contains a young, hot star cluster, NGC6611, visible with modest backyard telescopes, which is sculpting and illuminating the surrounding gas and dust. The result is a huge, hollowed-out cavity and pillars, each several light-years long.

The new Herschel image shows the pillars and the wide field of gas and dust around them. Captured in far-infrared wavelengths, the image allows astronomers to see inside the pillars and structures in the region. Herschel's image also makes it possible to search for young stars over a much wider region, and come to a much fuller understanding of the creative and destructive forces inside the Eagle nebula.

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