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Monday, January 20, at 10:00 GMT (which is 5:00 a.m. for U.S. East Coasters like me) the wake-up call will ring on ESA’s Rosetta spacecraft, bringing it out of hibernation after over two and a half years in preparation of its upcoming and highly-anticipated rendezvous with a comet. The wake-up will incite the warming of Rosetta’s star trackers, which allow it to determine its orientation in space. Six hours later its thrusters will fire to stop its slow rotation and ensure that its solar arrays are receiving the right amount of sunlight. ... After nearly a decade of soaring through...

Rosetta, the first spacecraft built to orbit a comet and land a probe on these icy nomads, is now waking up after more than two years of slumber, and videos filmed as part of an international competition will help greet the spacecraft after it awakens. Comets are some of the most primitive building blocks of the solar system, with many dating to soon after its formation. Comets also likely helped seed Earth with water and other ingredients of life. By analyzing the composition of the comet, the European Space Agency's Rosetta spacecraft will help scientists learn more about the role...

A European probe awoke from a deep sleep Monday (Jan. 20) to gear up for an unprecedented comet rendezvous and landing this year that will cap a 10-year voyage across the solar system. After two and a half years in hibernation, the European Space Agency's Rosetta spacecraft emerged from its slumber while cruising nearly 418 million miles (673 million kilometers) from the sun. The wakeup call, which was due to begin at 5 a.m. EST (1000 GMT), took hours as Rosetta switched on heaters to warm itself after its long night in the cold depths of space.

The comet 67P/Churyumov-Gerasimenko may actually be two objects stitched together. New images from ESA's Rosetta spacecraft show an odd constriction near the middle of the comet, suggesting that two clumps of matter may have merged in what scientists call a contact binary. The conclusions are preliminary, as Rosetta was still roughly 12,000 kilometers away from the comet when the images were taken. The comet could also have had a more regular single shape with parts carved out through impacts or ice melting as the object circled the sun, mission scientists say. They will have more details about the comet's...

After a decade in space and 4 billion miles, Europe's Rosetta spacecraft has made history: For the first time ever, a robotic probe from Earth is flying with a comet and will soon enter orbit. The European Space Agency's Rosetta spacecraft arrived at its target, Comet 67P/Churyumov-Gerasimenko, today (Aug. 6) to end a 10-year journey across the solar system. The spacecraft performed an engine burn that brought it about 62 miles (100 kilometers) from the comet's surface. Comet 67P/C-G and Rosetta are now flying about 251 million miles (450 million kilometers) from Earth. Engineers on the ground had to program...

Rosetta has arrived! After traveling more than ten years, ESA’s Rosetta spacecraft reached comet 67P/Churyumov-Gerasimenko. These most recent images shared from the Rosetta team were obtained from a distance of 285 kilometers above 67P’s surface, and scientists say they surpass all pictures taken from earlier space missions of cometary surfaces. Visible are steep slopes and precipices, sharp-edged rock structure, prominent pits, and smooth, wide plains. “It’s incredible how full of variation this surface is,” said Holger Sierks, the principal investigator of the OSIRIS imaging system on Rosetta. “We have never seen anything like this before in such great detail. “Today,...

...while it's one thing to say that the nucleus of Comet 67P/Churyumov-Gerasimenko is about three by five kilometers in diameter, it's quite another to see it in context with more familiar objects. Think about it—a comet as tall as Mt Fuji! At the time of this writing Rosetta is 35 days out on approach to Comet 67P/C-G, at a distance of about 51,000 km (31,700 miles) and closing. Three "big burn" maneuvers have already been performed between May 7 and June 4 to adjust the spacecraft's course toward the incoming comet, and after smaller ones on June 18 and July...

For all the wonder that comets evoke, we on Earth never see directly what whips up the coma and tail. Even professional telescopes can’t burrow through the dust and vapor cloaking the nucleus to distinguish the clear outline of a comet’s heart. The only way to see one is to fly a camera there. Rosetta took 10 years to reach 67P/C-G, a craggy, boot-shaped body that resembles an asteroid in appearance but with key differences. Asteroids shown in close up photos often display typical bowl-shaped impact craters. From the photos to date, 67P/C-G’s ‘craters’ look shallow and flat in comparison...

Explanation: Why does this comet's nucleus have two components? The surprising discovery that Comet 67P/Churyumov–Gerasimenko has a double nucleus came late last week as ESA's robotic interplanetary spacecraft Rosetta continued its approach toward the ancient comet's core. Speculative ideas on how the double core was created include, currently, that Comet Churyumov–Gerasimenko is actually the result of the merger of two comets, that the comet is a loose pile of rubble pulled apart by tidal forces, that ice evaporation on the comet has been asymmetric, or that the comet has undergone some sort of explosive event. Pictured above, the comet's unusual...

Explanation: The Rosetta spacecraft captured this remarkable series of 9 frames between March 27 and May 4, as it closed from 5 million to 2 million kilometers of its target comet. Cruising along a 6.5 year orbit toward closest approach to the Sun next year, periodic comet 67P/Churyumov-Gerasimenko is seen moving past a distant background of stars in Ophiuchus and globular star cluster M107. The comet's developing coma is actually visible by the end of the sequence, extending for some 1300 km into space. Rosetta is scheduled for an early August rendezvous with the comet's nucleus. Now clearly active, the...

DARMSTADT, Germany - A European spacecraft was on course to zip past Mars on Sunday, a crucial maneuver in its meandering, 10-year voyage through the solar system to make the first soft landing on a comet. The Rosetta craft is to pass within just 150 miles of the Martian surface, using the planet's gravity to change course and head for similar close encounters with Earth later this year and in 2009. The momentum gained from these flybys will sling the spacecraft toward its final rendezvous with the comet 67/Churyumov-Gerasimenko. Rosetta must swing around Mars on exactly the right course, and...

Explanation: On August 3rd, the Rosetta spacecraft's narrow angle camera captured this stunning image of the nucleus of Comet 67P/Churyumov-Gerasimenko. After 10 years and 6.5 billion kilometers of travel along gravity assist trajectories looping through interplanetary space, Rosetta had approached to within 285 kilometers of its target. The curious double-lobed shape of the nucleus is revealed in amazing detail at an image resolution of 5.3 meters per pixel. About 4 kilometers across, the comet nucleus is presently just over 400 million kilometers from Earth, between the orbits of Jupiter and Mars. Now the first spacecraft to achieve a delicate orbit...

Explanation: What does it look like to approach a comet? Early this month humanity received a new rendition as the robotic Rosetta spacecraft went right up to -- and began orbiting -- the nucleus of Comet 67P/Churyumov-Gerasimenko. This approach turned out to be particularly fascinating because the comet nucleus first revealed itself to have an unexpected double structure, and later showed off an unusual and craggily surface. The above 101-frame time-lapse video details the approach of the spacecraft from August 1 through August 6. The icy comet's core is the size of a mountain and rotates every 12.7 hours. Rosetta's...

Hidden among the four new images of Comet 67P/Churyumov-Gerasimenko released by ESA this week are a pair of dusty jets shooting from the nucleus of Comet Churyumov-Gerasimenko. The photos were taken September 2, 2014 and posted as a mosaic of four separate images. I re-assembled the four, albeit imperfectly, and added some additional contrast to better show the dual geyser of ice crystals mixed with dust venting from the nucleus. ... Jets or sprays of vaporizing ice are what gives a comet its lively appearance. Dust released with water vapor is ultimately pushed back by the pressure of sunlight to...

Explanation: Spacecraft Rosetta continues to approach, circle, and map Comet Churyumov-Gerasimenko. Crossing the inner Solar System for ten years to reach the vicinity of the comet last month, the robotic spacecraft continues to image the unusual double-lobed comet nucleus. The reconstructed-color image featured, taken about 10 days ago, indicates how dark this comet nucleus is. On the average, the comet's surface reflects only about four percent of impinging visible light, making it as dark as coal. Comet 67P/Churyumov–Gerasimenko spans about four kilometers in length and has a surface gravity so low that an astronaut could jump off of it. In...

  Jessica Orwig September. 18, 2014.Ten years ago the European Space Agency launched Rosetta, a first-of-its-kind spacecraft on a mission to meet a comet. That comet? 67P/Churyumov-Gerasimenko. It finally accomplished that goal earlier this month — getting into the comet's orbit. But it's not done yet. This November, Rosetta will deploy a small probe that, if successful, will land on the comet — the first time we've ever made contact with a space rock (intentionally). Before Rosetta, we knew comet 67P/Churyumov-Gerasimenko as just a speck of light — as we do most comets. It's hard to really see what...

Explanation: This Rosetta spacecraft selfie was snapped on October 7th. At the time the spacecraft was about 472 million kilometers from planet Earth, but only 16 kilometers from the surface of comet 67P/Churyumov-Gerasimenko. Looming beyond the spacecraft near the top of the frame, dust and gas stream away from the comet's curious double-lobed nucleus and bright sunlight glints off one of Rosetta's 14 meter long solar arrays. In fact, two exposures, one short and one long, were combined to record the dramatic high contrast scene using the CIVA camera system on Rosetta's still-attached Philae lander. Its chosen primary landing site...

The comet that the Rosetta spacecraft is visiting is shedding more dust as machine and Solar System body get closer to the Sun. While activity was first seen at the “neck” of the rubber-duckie shaped comet a few weeks ago, now scientists are seeing jets spring from across the comet. This is just one signal of cometary activity picking up as 67P gets closer to the Sun. For the moment, it appears the prime landing site is still safe enough for Philae to land on Nov. 19, officials said, while noting there is a jet about a kilometer away that...

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