Astro News Briefs: February 11–17

A Solar-System Signpost?

February 15, 2002 | Some young stars are surrounded by disks of dust left over from their formation. Eventually this material may coalesce into planets. But some older stars have dust disks too. Astronomers think these may be produced by collisions among comets, asteroids, and meteoroids in mature planetary systems. A new study by Markus Landgraf (European Space Agency) reveals that our own Sun is surrounded by such a disk, suggesting that the best place to hunt for planetary systems like our own is around long-lived stars encircled by dust.

To learn more about Landgraf's findings, see ESA's press release:

Countdown to Hubble Servicing

February 15, 2002 | NASA is holding firm to its planned February 28th liftoff of the Space Shuttle Columbia on the next mission to service the Hubble Space Telescope. During the 11-day flight astronauts will install a powerful new ultraviolet- and visible-light camera, restore an infrared camera to operation, and attach new solar-cell arrays.

For a preview of the flight, see the March 2002 issue of Sky & Telescope or visit the mission's Web site:

Student Scope Online

February 14, 2002 | Very few high-school students have had access to dark-sky observatories with state-of-the-art equipment -- until today. Thanks to a new program called the Student Telescope Network (STN), any qualified high-schooler can now use the Internet to control a telescope and electronic camera in New Mexico. A joint effort by the Astronomical League (AL), the University of Denver, New Mexico Skies, and Software Bisque, STN can be used for classroom instruction, astronomical research, science-fair projects, and other applications.

Read more at the AL's Youth Activities Committee Web site:

The Moon's Soft Center

February 14, 2002 | Scientists at NASA's Jet Propulsion Laboratory have obtained new evidence that the Moon has a partially molten core. By bouncing laser pulses off reflectors left by the Apollo astronauts, James Williams and his colleagues measured the lunar surface's response to tidal forces from the Earth and Sun. The degree of elasticity they found suggests that a zone in the Moon's deep interior is slushy, resurrecting an idea first proposed several decades ago during the heyday of lunar exploration.

See the NASA/JPL press release for details:

Newborn Millisecond Pulsar?

February 13, 2002 | New observations of an unusual binary star in a globular cluster suggest that we're witnessing the birth of a so-called millisecond pulsar. Gas accreted from a bloated red-giant companion has apparently "spun-up" the highly magnetized neutron star to a dizzying rate of 274 rotations per second. Isolated pulsars spin much more slowly. Francesco Ferraro (Bologna Astronomical Observatory) and his colleagues made their discovery using the Hubble Space Telescope (HST) and the Parkes radio telescope in Australia.

More information, including the Hubble image and an artist's conception of the pulsar and its swollen companion, may be found at the European Space Agency's HST Web site:

Surveyor Shoots Mars

February 11, 2002 | A year after completing its primary mission of mapping the red planet in unprecedented detail, Mars Global Surveyor (MGS) continues to shoot high-resolution images of Martian surface features. Several new pictures from the Mars Orbiter Camera, including close-ups of the polar ice caps, were released today to celebrate the spacecraft's longevity.

Selected images from the first year of MGS's extended mission are available on the Web site of Malin Space Science Systems:

Solar Science Gets a Lift

February 11, 2002 | Scientists have begun a detailed study of some of the most important — but least understood — layers of Earth's atmosphere. NASA's TIMED (Thermosphere, Ionosphere, Mesosphere, Energetics, and Dynamics) spacecraft, launched on December 7th and now finished with its orbital checkout, is probing the thin air at altitudes of 65 to 175 kilometers (40 to 110 miles). This is where solar energy is first deposited into Earth's ecosystem. TIMED is the first of six planned solar-terrestrial probes designed to determine how the Sun's energy output varies and how our planet responds.

To learn more about TIMED, visit the mission's Web site at the Johns Hopkins University Applied Physics Laboratory: