SURPRISING ANATOMY OF A COMET

Findings from a historic encounter between NASA’s Stardust spacecraft and a comet revealed much stranger findings than previously believed. The comet’s rigid surface, dotted with towering pinnacles, plunging craters, steep cliffs, and dozens of jets spewing violently, has surprised scientists.

“We thought Comet Wild 2 would be like a dirty, black, fluffy snowball,” said Stardust Principal Investigator Dr. Donald Brownlee of the University of Washington, Seattle. “Instead, it was mind-boggling to see the diverse landscape in the first pictures from Stardust, including spires, pits and craters, which must be supported by a cohesive surface,” Brownlee said.
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REMOTE HEALTH MONITORS

A lightweight, portable device developed by NASA scientists is enabling physicians to monitor the health and safety of explorers in remote locations on Earth. It may eventually be used in space to monitor astronauts during space travel.

The wireless LifeGuard system watched over the vital signs of several expedition members who sampled soils and water from the world’s highest alpine lake, nearly 20,000 feet up the Licancabur volcano, on the border between Chile and Bolivia, last year.
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HURRICANES MAY HELP PLANKTON BLOOM

Whenever a hurricane races across the Atlantic Ocean, chances are phytoplankton will bloom behind it. According to a new study using NASA satellite data, these phytoplankton blooms may also affect the Earth’s climate and carbon cycle.

Dr. Steven Babin, a researcher at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., studied 13 North Atlantic hurricanes between 1998 and 2001. Ocean color data from the SeaWiFS instrument on the SeaStar satellite were used to analyze levels of chlorophyll, the green pigment in plants. The satellite images showed tiny microscopic ocean plants, called phytoplankton, bloomed following the storms.
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Arianespace to Launch Record Size Satellite

The Arianespace Flight 163 Anik F2 satellite payload is at the Spaceport being readied for flight. This satellite – one of the heaviest commercial telecommunications payloads ever built for operation in geostationary orbit — is now undergoing checkout in the Spaceport’s S5 facility in preparation for a July 9 launch on Ariane 5.

Arianespace Web site ttp://www.arianespace.com

SO-50 satellite now available to all Hams

AMSAT-NA says thethe SO-50 satellite–also known as SaudiSat-1C–now is available to all, and users can switch on the Mode J transponder via a CTCSS tone.

Previously, only one of the three control operators could turn on the spacecraft for amateur communication. Here’s the procedure: Transmit on 145.850 MHz (taking Doppler effect into account) using a CTCSS tone of 74.4 Hz to arm the onboard 10-minute timer. Then, transmit FM voice on 145.850 MHz using a CTCSS tone of 67.0 Hz to actuate the repeater within the 10-minute window (SO-50 takes a half second or so to start transmitting once a signal is received, so users should pause briefly before talking). SO-50’s downlink frequency is 436.800 MHz. Sending the 74.4 Hz CTCSS tone again within the 10-minute window resets the timer.

Launched in December 2002, SO-50 sports a quarter-wave vertical receiving antenna mounted at the top corner of the spacecraft. The transmitter runs 250 mW into a quarter-wave antenna mounted on the bottom corner of the spacecraft and canted 45 degrees inward.

http://www.amsat.org/amsat/sats/n7hpr/so50.html