Brighter Neptune suggests a planetary change of seasons

progressive increase in the brightness of the planet Neptune suggests that, like Earth, the distant planet has seasons. Observations of Neptune made during a six-year period with NASA’s Hubble Space Telescope by a group of scientists from the University of Wisconsin-Madison and NASA’s Jet Propulsion Laboratory (JPL) show that the planet is exhibiting a significant increase in brightness. The changes, observed mostly in the planet’s southern hemisphere, show a distinct increase in the amount and brightness of the banded cloud features that are a distinctive feature of the planet.

Featherweight Jupiter Moon Is Likely a Jumble of Pieces

NASA’s Galileo spacecraft continues to deliver surprises with the discovery that Jupiter’s potato-shaped inner moon, named Amalthea, appears to have a very low density, indicating it is full of holes. “The density is unexpectedly low,” said Dr. John D. Anderson, an astronomer at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “Amalthea is apparently a loosely packed pile of rubble.” The empty gaps between solid chunks likely take up more of the moon’s total volume than the solid pieces, and even the chunks are probably material that is not dense enough to fit some theories about the origin of Jupiter’s moons. “Amalthea now seems more likely to be mostly rock with maybe a little ice, rather than a denser mix of rock and iron,” said JPL’s Dr. Torrence Johnson, project scientist for Galileo.

NASA Research Offers Explanation for Earth’s Bulging Waistline

A team of researchers from NASA’s Jet Propulsion Laboratory, Pasadena, Calif., and the Royal Observatory of Belgium has apparently solved a recently observed mystery regarding changes to the physical shape of Earth and its gravity field. The answer, they found, appears to lie in the melting of sub-polar glaciers and mass shifts in the Southern, Pacific and Indian Oceans associated with global-scale climate changes.

NASA Awards Caltech Five-Year, $8 billion JPL Contract

NASA has awarded the California Institute of Technology a new five-year contract to manage the Jet Propulsion Laboratory. It is estimated the contract will cover more than $8 billion worth of work. The contract extends for five years the JPL agreement between Caltech and NASA for management of JPL beyond its current expiration date of Sept. 30, 2003. The NASA contract includes a new provision that, based on performance reviews, may extend the contract period of performance for up to an additional five years.

Physicists to ‘boost’ satellite with microwaves

A California physicist will announce plans for the first known attempt to push a spacecraft into the Earth’s orbit with energy beamed up from the ground. The satellite will be called the Cosmos Sail, the first solar-sail craft to orbit Earth. The physics team developed the sail with researchers from the Jet Propulsion Laboratory. Made from lightweight layers of aluminized mylar, the sail will allow a craft to be propelled from low orbit to high orbit and ultimately into interplanetary space, driven by microwave energy, similar to the way wind pushes a sailboat across the sea.

NASA’s Stardust Comet-Chaser Passes Asteroid Test

All systems on NASA’s Stardust spacecraft performed successfully when tested in a flyby of asteroid Annefrank on Friday, heightening anticipation for Stardust’s encounter with its primary target, comet Wild 2, 14 months from now. As a bonus, Stardust discovered that Annefrank is about twice the size anticipated, but with a dimmer surface. The dimmer surface increased the challenge of sighting the object as the spacecraft approached.

Scientists Boost Tally at Uranus

A new moon of the planet Uranus has been discovered and confirmed by a team of astronomers at NASA’s Jet Propulsion Laboratory. This most-recently discovered natural satellite, named S/2001 U 1, brings the total number of confirmed uranian moons to 21. The new kid on the block — and five others like it — have very irregular, eccentric orbits that don’t share the same orbital plane as the larger moons of Uranus. Ranging in size from 10 to 20 kilometers, these moons are thought to be remnants of ancient collisions that occurred at the early stage of planetary formation.

NASA Music Out of this World

With scientific instruments on NASA’s Voyagers, Galileo, Cassini and more than two dozen other spacecraft, University of Iowa physicist Dr. Don Gurnett has been recording waves that course through the thin, electrically charged gas pervading the near-vacuum of outer space. Gurnett converted the recorded plasma waves into sounds, much as a receiver turns radio waves into sound waves. “I’ve got a cardboard box full of cassette tapes of sounds that I’ve collected over nearly 40 years,” he said. Gurnett’s tapes have inspired a 10-movement musical composition called “Sun Rings.” The Grammy-nominated Kronos Quartet will premiere “Rings” this month.

NASA to Develop Biohazard ‘Smoke’ Detector

Researchers at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., have demonstrated a prototype device that automatically and continuously monitors the air for the presence of bacterial spores. The result is a novel alarm capability reminiscent of smoke detectors. Current methods for detecting bacterial spores, such as anthrax, require a trained operator. The large number of trained monitors required, with associated costs, limits widespread implementation of these methods.