Tag Archives: NASA

NASA Telescope Helps Confirm Nature of Dark Energy

PASADENA, Calif. — A five-year survey of 200,000 galaxies, stretching back seven billion years in cosmic time, has led to one of the best independent confirmations that dark energy is driving our universe apart at accelerating speeds. The survey used data from NASA’s space-based Galaxy Evolution Explorer and the Anglo-Australian Telescope on Siding Spring Mountain in Australia.

The findings offer new support for the favored theory of how dark energy works — as a constant force, uniformly affecting the universe and propelling its runaway expansion. They contradict an alternate theory, where gravity, not dark energy, is the force pushing space apart. According to this alternate theory, with which the new survey results are not consistent, Albert Einstein’s concept of gravity is wrong, and gravity becomes repulsive instead of attractive when acting at great distances. (more…)

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Free-Floating Planets May be More Common Than Stars

PASADENA, Calif. — Astronomers, including a NASA-funded team member, have discovered a new class of Jupiter-sized planets floating alone in the dark of space, away from the light of a star. The team believes these lone worlds were probably ejected from developing planetary systems.

The discovery is based on a joint Japan-New Zealand survey that scanned the center of the Milky Way galaxy during 2006 and 2007, revealing evidence for up to 10 free-floating planets roughly the mass of Jupiter. The isolated orbs, also known as orphan planets, are difficult to spot, and had gone undetected until now. The newfound planets are located at an average approximate distance of 10,000 to 20,000 light-years from Earth. (more…)

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NASA Mission Will Observe Earth’s Salty Seas

PASADENA, Calif. – Final preparations are under way for the June 9 launch of the international Aquarius/SAC-D observatory. The mission’s primary instrument, Aquarius, will study interactions between ocean circulation, the water cycle and climate by measuring ocean surface salinity.

Engineers at Vandenberg Air Force Base in California are performing final tests before mating Aquarius/SAC-D to its Delta II rocket. The mission is a collaboration between NASA and Argentina’s space agency, Comision Nacional de Actividades Espaciales (CONAE), with participation from Brazil, Canada, France and Italy. SAC stands for Satelite de Applicaciones Cientificas. Aquarius was built by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and the agency’s Goddard Space Flight Center in Greenbelt, Md. (more…)

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Why Some Planets Orbit the Wrong Way; Extrasolar Insights into Our Solar System

More than 500 extrasolar planets–planets that orbit stars other than the sun–have been discovered since 1995. But only in the last few years have astronomers observed that in some of these systems, the star is spinning one way and the planet is orbiting that star in the opposite direction.

“That’s really weird, and it’s even weirder because the planet is so close to the star,” said Frederic A. Rasio, a theoretical astrophysicist at Northwestern University. “How can one be spinning one way and the other orbiting exactly the other way? It’s crazy. It so obviously violates our most basic picture of planet and star formation.” (more…)

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NASA’s Galileo Reveals Magma ‘Ocean’ Beneath Surface of Jupiter’s Moon

A new analysis of data from NASA’s Galileo spacecraft has revealed that beneath the surface of Jupiter’s volcanic moon Io is an “ocean” of molten or partially molten magma.

The finding, from a study published May 13 in the journal Science, is the first direct confirmation of such a magma layer on Io and explains why the moon is the most volcanic object known in the solar system. The research was conducted by scientists from UCLA, UC Santa Cruz and the University of Michigan–Ann Arbor. (more…)

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Aquarius to Illuminate Links Between Salt, Climate

When NASA’s salt-seeking Aquarius instrument ascends to the heavens this June, the moon above its launch site at California’s Vandenberg Air Force Base won’t be in the seventh house, and Jupiter’s latest alignment with Mars will be weeks in the past, in contrast to the lyrics of the song from the popular Broadway musical “Hair.” Yet for the science team eagerly awaiting Aquarius’ ocean surface salinity data, the dawning of NASA’s “Age of Aquarius” promises revelations on how salinity is linked to Earth’s water cycle, ocean circulation and climate.

Salinity – the concentration of salt – on the ocean surface is a key missing puzzle piece in satellite studies of Earth that will improve our understanding of how the ocean and atmosphere are coupled and work in tandem to affect our climate. While satellites already measure sea surface temperature and winds, rainfall, water vapor, sea level, and ocean color, measurements of ocean surface salinity have, until quite recently, been limited to sparse data collected from ships, buoys and a small number of airborne science campaigns. (more…)

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Dawn Reaches Milestone Approaching Asteroid Vesta

PASADENA, Calif. — NASA’s Dawn spacecraft has reached its official approach phase to the asteroid Vesta and will begin using cameras for the first time to aid navigation for an expected July 16 orbital encounter. The large asteroid is known as a protoplanet — a celestial body that almost formed into a planet.

At the start of this three-month final approach to this massive body in the asteroid belt, Dawn is 1.21 million kilometers (752,000 miles) from Vesta, or about three times the distance between Earth and the moon. During the approach phase, the spacecraft’s main activity will be thrusting with a special, hyper-efficient ion engine that uses electricity to ionize and accelerate xenon. The 12-inch-wide ion thrusters provide less thrust than conventional engines, but will provide propulsion for years during the mission and provide far greater capability to change velocity. (more…)

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Asteroids Collide at 11,000 Miles Per Hour; Scientists Study Debris

Scientists have captured and studied the collision of two asteroids for only the second time in the history of astronomy. In the May 20 edition of the Astrophysical Journal Letters (currently online), UCLA’s David Jewitt and colleagues report on observations from NASA’s Hubble Space Telescope of a large asteroid that was hit by a much smaller one.

On Dec. 11, 2010, astronomers noticed that an asteroid known as (596) Scheila had unexpectedly brightened and was sporting short-lived dust plumes. Data from NASA’s Swift satellite and Hubble Space Telescope showed that these changes likely occurred after Scheila was struck by a much smaller asteroid, probably in late November or early December. The shape, evolution and content of the plumes enabled the scientists to reconstruct what occurred. (more…)

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