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Landing on Titan: Huygens probe stars in new movies EUROPEAN SPACE AGENCY NEWS RELEASE Posted: May 7, 2006 A little more than one year after the spectacular descent of the European Space Agency's Huygens on Saturn's giant moon Titan, scientists from the probe's Descent Imager/Spectral Radiometer (DISR) have released two new movies of the descent. These represent the best visual product from the mission obtained so far and most realistic way yet to experience the landing on a far-away world. These movies were built thanks to the data collected by DISR on 14 January 2005, during the 147-minutes plunge through Titan's thick orange-brown atmosphere to a soft sandy riverbed. The data were analysed for months after the landing. The movie "View from Huygens on 14 January 2005" shows in 4 minutes 40 seconds what the probe actually "saw" within the few hours of the descent and the eventual landing. "At first the Huygens camera just saw haze over the distant surface," said DISR team member Erich Karkoschka, from the DISR team at the University of Arizona and creator of the movies. "The haze started to clear only at about 60 kilometres altitude, making it possible to resolve surface features as large as 100 metres" he continued. "But only after landing could the probe's camera resolve little grains of sand millions and millions times smaller than Titan. A movie is a perfect medium to show such a huge change of scale." The second, more technical movie (called "DISR movie"), shows DISR's 4-hour operating life in less than five minutes, too. A detailed caption to explain how the movie is structured is provided with the video. The scientists analyzed Huygens' speed, direction of motion, rotation and swinging during descent, represented in this movie. It also features Huygens' trajectory views from the south, indication of the large and unexpected parachute movements, the changing direction of view as Huygens rotates along with the relative positions of the sun and Cassini, and a clock to follow the actual sequence of events. Sounds from a left speaker trace Huygens' motion, with tones changing with rotational speed and the tilt of the parachute. There are also clicks that clock the rotational counter, as well as sounds for the probe's heat shield hitting Titan's atmosphere, parachute deployments, heat shield release, jettison of the DISR cover and touch down. Sounds from a right speaker go with DISR activity. There's a continuous tone that represents the strength of Huygens' signal to Cassini. "DISR was a very complicated instrument," Karkoschka said. "It had to be programmed to take its 3500 exposures in a way to get the most science. It had to decide where and when to take exposures." DISR was designed in the early to mid 1990s, when the best images returned by the Voyager missions showed Titan as a featureless, hazy disk. "We didn't know the dynamics of Titan's atmosphere very well, and we didn't know how fast Huygens would rotate and swing," Karkoschka said. "It was an extremely challenging programming task to make DISR work well under every imaginable condition." "These movies really demonstrate that the Huygens camera was very well designed for the job," said Jean-Pierre Lebreton, Huygens Project Scientist and Mission Manager at ESA. "They show so many different details of a landscape that covers only a tiny fraction (one thousandth) of Titan's surface. This makes me dream of what a possible future mission to Titan may return from this wonderful and fascinating Earth-like world", he concluded. The Huygens probe landing was the most distant touchdown ever made by a human-built spacecraft. The Cassini-Huygens mission to Saturn and Titan is a joint mission of NASA, the European Space Agency (ESA) and the Italian Space Agency (ASI). ESA supplied and manages the Huygens probe that descended to Titan's surface Jan. 14, 2005. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate in Washington, D.C. NASA funded the Descent Imager-Spectral Radiometer, which was built by Lockheed Martin. The DISR team members, headed by Research Professor Martin Tomasko at University of Arizona's Lunar and Planetary Laboratory (LPL), are based throughout the United States and Europe, with the largest contributing groups from the University of Arizona in the United States, the Max Planck Institute in Germany, and the Paris Observatory in Meudon, France. DISR was developed by the University of Arizona (with NASA funding) and by Lockheed Martin researchers. |
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A seven-person crew featuring payload specialists from France and Saudi Arabia flew aboard the June 1985 mission of space shuttle Discovery. They narrate the highlights of STS-51G in this post-flight film. Three communications satellites -- for Mexico, the Arab countries and the U.S. -- were launched from the payload bay. And the SPARTAN 1 astrophysics spacecraft was deployed from the shuttle's robot arm for a two-day freeflight to make its science observations before being retrieved and returned to Earth.
The flight of Spacelab 3 aboard Challenger in April/May 1985 was a week-long scientific research mission using a laboratory tucked in the shuttle's payload bay. Experiments focused on material and fluid behaviors in weightlessness, plus observations of monkeys in the lab. The crew also watched amazing auroral displays over Earth. This post-flight crew film shows the highlights of STS-51B and includes remarkable views out the shuttle cockpit window during launch showing the Chesapeake Bay, New York City and Cape Cod as Challenger soared up the eastern seaboard.
Discovery launched April 12, 1985 on the STS-51D mission. A U.S. military communications satellite, known as Leasat 3, failed to activate after its deployment from the payload bay. That set the stage for a spacewalk -- the shuttle program's first unplanned EVA -- to attach handcrafted "Flyswatter" objects on the shuttle robotic arm to hit a timing switch on the satellite. The rescue attempt did not succeed. Upon landing at Kennedy Space Center, Discovery blew a tire. The crew, including Senator Jake Garn of Utah, narrate this post-flight film of highlights from the week-long mission.
NASA managers hold this news conference April 28 to give an update on plans for the next space shuttle mission, the ongoing external fuel tank testing and debates over further modifications.
The Boeing Delta 2 rocket carrying the CALIPSO and CloudSat atmospheric research spacecraft lifts off at 3:02 a.m. local time April 28 from Vandenberg Air Force Base, California.
Inside the Vehicle Assembly Building, the external fuel tank for the STS-121 space shuttle mission is hoisted into position for attachment with the twin solid rocket boosters atop a mobile launch platform. The tank, ET-119, will carry the liquid oxygen and liquid hydrogen to feed Discovery's three main engines during launch.
In preparation for space shuttle Discovery's departure from its Orbiter Processing Facility hangar for rollover to the Vehicle Assembly Building and mating with the tank and boosters, the ship's 60-foot long payload bay doors are swung shut.