Alpha Centauri 2

Community => Recreation Commons => Destination: Alpha Centauri => Topic started by: Buster's Uncle on January 19, 2014, 10:05:56 pm

Title: Comet-Chasing Rosetta Spacecraft Wakes from Deep Sleep Monday: Watch It Live
Post by: Buster's Uncle on January 19, 2014, 10:05:56 pm

Robotic probe to awaken for comet rendezvous, landing
Reuters
By Irene Klotz  16 minutes ago



(Reuters) - After a 10-year journey, Europe's Rosetta spacecraft is due to end its hibernation on Monday and prepare for an unprecedented mission to orbit a comet and dispatch a lander to the surface.

Rosetta's on-board alarm clock is due to go off at 5 a.m. EST (1000 GMT), but it will take the spacecraft about seven hours to warm up its star tracking navigation gear, fire up rocket thrusters to slow its spin, turn on its transmitter and beam a message back to Earth, the European Space Agency said in a status report posted on its website.

The probe, presently located about 500 million miles (about 800 million km) from Earth and just shy of Jupiter's orbit, is so far away that its radio transmissions, traveling at the speed of light, will take 45 minutes to reach listening stations in California and Australia.

Ground control teams hope to have confirmation of Rosetta's resuscitation by 1:30 p.m. EST (1830 GMT), the European Space Agency said.

The spacecraft, which carries a 220-pound (100 kg) lander called Philae, has been hibernating for most of the past three years to save power. It is due to reach a 2.4-mile (4 meter) diameter comet called 67P/Churyumov-Gerasimenko in August.

Unlike previous comet probes, Rosetta won't just sail by. The spacecraft is designed to put itself into orbit around 67P for more than a year of close-up studies.

Comets are believed to be the pristine leftover remains from the formation of the solar system some 4.6 billion years ago. Scientists hope the mission will provide more clues about how the solar system came into existence, much like the Rosetta Stone, for which the spacecraft is named, provided a blueprint for deciphering ancient Egyptian hieroglyphs.

"Rosetta should become a key element for our understanding of the history of the solar system," Stephan Ulamec, a Rosetta project manager, said in an interview with Reuters last month.

One of Rosetta's first tasks will be to scout for a suitable landing location for its piggyback-riding Philae probe. Scientists are particularly keen to conduct organic chemistry experiments on samples drilled out from inside the comet's body.

"It would be really interesting to find out whether the organic chemistry that is relevant for life is there on comets," Ulamec said.

Engineers who designed the lander did not know what type of terrain they would find on the comet's surface. It is outfitted with twin harpoons laced with tethers that will be fired into the comet's surface to anchor Philae and keep it from bouncing back into space after touchdown.

Europe spent about 1 billion euros ($1.35 billion) on the mission, which is due to run at least until the end of 2015.


http://news.yahoo.com/robotic-probe-awaken-comet-rendezvous-landing-213247157--sector.html (http://news.yahoo.com/robotic-probe-awaken-comet-rendezvous-landing-213247157--sector.html)

Title: Comet-Chasing Rosetta Spacecraft Wakes from Deep Sleep Monday: Watch It Live
Post by: Buster's Uncle on January 19, 2014, 11:33:59 pm

Comet-Chasing Rosetta Spacecraft Wakes from Deep Sleep Monday: Watch It Live
SPACE.com
by Tariq Malik, Managing Editor  1 hour ago


(http://l1.yimg.com/bt/api/res/1.2/EOMJLH.G7ZaUeS7aKJiLjQ--/YXBwaWQ9eW5ld3M7Zmk9ZmlsbDtoPTQzMTtweW9mZj0wO3E9NzU7dz01NzU-/http://media.zenfs.com/en_US/News/SPACE.com/Comet-Chasing_Rosetta_Spacecraft_Wakes_from-deb6b225a2188049acf42e248cfe09f9)
In August 2014, the ESA's Rosetta Spacecraft will rendezvous with Comet 67P/Churyumov-Gerasimenko



A European spacecraft destined to visit a comet later this year will get the ultimate wake-up call Monday (Jan. 20) and you can watch it live online.

After more than two years in a deep sleep, the European Space Agency's Rosetta spacecraft is due to awake from its "hibernation" mode at 5 a.m. EST (1000 GMT) on Monday to gear up for an August arrival at its comet target. To mark the occasion, ESA officials will celebrate with a special day-long series of press briefings from the European Space Operations Center in Darmstadt, Germany. 

You can watch the Rosetta comet probe wake-up webcast live here (http://www.space.com/17933-nasa-television-webcasts-live-space-tv.html) beginning at 4:15 a.m. EST (0915 GMT), courtesy of ESA. The webcast will run from 4:15 a.m. EST to at least 1:30 p.m. EST (1830 GMT). In the Central European Time zone, the schedule runs from 10:15 to 19:30 CET, according an ESA update.

The Rosetta spacecraft launched in 2004 on a decade-long journey to the Comet 67P/Churyumov-Gerasimenko. The spacecraft is slated to arrive in orbit around the comet in August of this year to begin studying its target and, ultimately, land the small Philae lander on the comet's surface.

Rosetta flew by Earth three times, and Mars once, to build up enough speed to reach the comet. Along the way, it also visited two asteroids —Steins and Lutetia.

But in mid-2011, Rosetta entered a 31-month "hibernation" as it sailed out toward the orbit of Jupiter — where the available sunlight was too low to power all of its systems. Only the probe's main computer and some heaters stayed on to keep it alive, ESA officials said.

Rosetta's internal clock is programmed to wake the comet-chasing spacecraft on Monday to begin preparing for the August comet encounter. ESA officials have described it as "the most important alarm clock in the solar system."

It will take Rosetta several hours after its 5 a.m. reactivation to warm its star trackers enough to orient itself to face Earth and beam its wake-up announcement to Earth.

"Because of Rosetta's vast distance — just over 807 million kilometers (501 million miles) from Earth — it will take 45 minutes for the signal to reach the ground stations," ESA officials wrote in a statement. "The first opportunity for receiving a signal on Earth is expected between 17:30 GMT and 18:30 GMT (12:30 to 1:30 p.m. EST)."

ESA's deep-space listening station in New Norcia, Australia, will be awaiting that signal, as will NASA's Deep Space Network radio antennas in Canberra, Australia, and Goldstone, Calif. Once the first signal is received, it will be transmitted to ESA's Space Operations Center and announced publicly using the Rosetta mission's Twitter feed @ESA_Rosetta.

Currently, Rosetta is nearly 5.6 million miles (9 million km) from Comet 67P/Churyumov-Gerasimenko, but the probe is expected to close that gap to about 1.2 million miles (2 million km) by May, when it is scheduled to fire its thrusters to place it on a trajectory to arrive at the comet in August. The Philae lander is expected to be released to land on the comet in November, according to ESA officials.

"Comets are considered to be the primitive building blocks of the Solar System and likely helped to 'seed' Earth with water, and perhaps even the ingredients for life," ESA officials wrote in a statement. "But many fundamental questions about these enigmatic objects remain, and through its comprehensive, close-up study of Comet 67P/Churyumov–Gerasimenko, Rosetta aims to unlock the secrets within."


http://news.yahoo.com/comet-chasing-rosetta-spacecraft-wakes-deep-sleep-monday-220744436.html (http://news.yahoo.com/comet-chasing-rosetta-spacecraft-wakes-deep-sleep-monday-220744436.html)