Tag Archives: earth

Probes Suggest Magnetic Bubbles at Solar System Edge

PASADENA, Calif. –– Observations from NASA’s Voyager spacecraft, humanity’s farthest deep space sentinels, suggest the edge of our solar system may not be smooth, but filled with a turbulent sea of magnetic bubbles.

While using a new computer model to analyze Voyager data, scientists found the sun’s distant magnetic field is made up of bubbles approximately 100 million miles (160 million kilometers) wide. The bubbles are created when magnetic field lines reorganize. The new model suggests the field lines are broken up into self-contained structures disconnected from the solar magnetic field. The findings are described in the June 9 edition of the Astrophysical Journal. (more…)

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New Map Reveals Giant Fjords Beneath East Antarctic Ice Sheet

AUSTIN, Texas — Scientists from the U.S., U.K. and Australia have used ice-penetrating radar to create the first high-resolution topographic map of one of the last uncharted regions of Earth, the Aurora Subglacial Basin, an immense ice-buried lowland in East Antarctica larger than Texas.

The map reveals some of the largest fjords or ice cut channels on Earth, providing important insights into the history of ice in Antarctica. The data will also help computer modelers improve their simulations of the past and future Antarctic ice sheet and its potential impact on global sea level. (more…)

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Mars: Red Planet’s Rapid Formation Explains Its Small Size Relative to Earth

*Mars developed far more quickly than our blue planet*

Mars developed in as little as two to four million years after the birth of the solar system, far more quickly than Earth, according to results of a new study published in this week’s issue of the journal Nature.

The red planet’s rapid formation helps explain why it is so small, say the study’s co-authors, Nicolas Dauphas at the University of Chicago and Ali Pourmand at the University of Miami. (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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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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Melting Ice on Arctic Islands a Major Player in Sea Level Rise

ANN ARBOR, Mich.— Melting glaciers and ice caps on Canadian Arctic islands play a much greater role in sea level rise than scientists previously thought, according to a new study led by a University of Michigan researcher.

The 550,000-square-mile Canadian Arctic Archipelago contains some 30,000 islands. Between 2004 and 2009, the region lost the equivalent of three-quarters of the water in Lake Erie, the study found. Warmer-than-usual temperatures in those years caused a rapid increase in the melting of glacier ice and snow, said Alex Gardner, a research fellow in the Department of Atmospheric, Oceanic and Space Sciences who led the project. The study is published online in Nature on April 20. (more…)

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