Rosetta Wakes Up, Phones Home, Starts Tweeting

The silence from the live video feed from the ESA’s space operations center in Darmstadt, Germany was almost deafening. Scientists and engineers were waiting to receive a signal from the Rosetta spacecraft, which was supposed to come out of hibernation today to begin its mission to Comet 67P/Churyumov-Gerasimenko in earnest. Finally, after waiting nearly 45 minutes into the window of time when the spacecraft was supposed to send a signal, a little blip appeared on the screens of the spectrum analyzers and the room erupted in cheers.

Data monitors from Rosetta showing the signal received back on Earth from the spacecraft. Credit: ESA.
Data monitors from Rosetta showing the signal received back on Earth from the spacecraft. Credit: ESA.

“After waiting over two and a half years, what is three-quarters of an hour!” said Fred Jansen, ESA’s Rosetta mission manager. “The spacecraft is there, it’s awake and the science team knows there are two busy years ahead of them. Now we have to work hard. Thanks to the team that achieved this.”

“I think I can speak on behalf of everyone here and everyone on Twitter: that was rather stressful!” said Matt Taylor, Rosetta project scientist. “The work begins now and I think we’ll have a fun-filled two years ahead, so let’s get on it!”

Soon after the signal arrived, the mission Twitter feed came alive, Tweeting “Hello World” in multiple languages.

Later in the day, as the team checked out the spacecraft, everything appeared in order and working well as systems began to start operating:

Rosetta was placed into hibernation in June 2011, with only the computer and several heaters remaining active as the spacecraft cruised out to nearly 800 million km from the warmth of the Sun, beyond the orbit of Jupiter.

Today, as Rosetta’s orbit came back to within 673 million km from the Sun, there was enough solar energy to power the spacecraft fully again and Rosetta’s pre-programmed internal ‘alarm clock’ woke up the spacecraft after a record 957 days of hibernation. After warming up its key navigation instruments, coming out of a stabilizing spin, and aiming its main radio antenna at Earth, Rosetta sent a signal to let mission operators know it had survived the most distant part of its journey.

The signal was received by NASA’s Goldstone ground station in California at 18:18 GMT during the first window of opportunity the spacecraft had to communicate with Earth.

The one-way light time on today, January 20, 2014 between Rosetta and Earth was about 44 minutes and 53 seconds over a distance of 807,224,610.74 km. Rosetta was about 9,188,540 km from the comet, closing up at about 800 m/second.

“This was one alarm clock not to hit snooze on, and after a tense day we are absolutely delighted to have our spacecraft awake and back online,” said Jansen.

Comets are considered the primitive building blocks of the Solar System and perhaps may have helped to ‘seed’ Earth with water, or even the ingredients for life. But many fundamental questions about these enigmatic objects remain, and through its comprehensive, in situ study of Comet 67P/Churyumov-Gerasimenko, Rosetta aims to unlock the secrets contained within.

“All other comet missions have been flybys, capturing fleeting moments in the life of these icy treasure chests,” said Taylor. “With Rosetta, we will track the evolution of a comet on a daily basis and for over a year, giving us a unique insight into a comet’s behavior and ultimately helping us to decipher their role in the formation of the Solar System.”

But first, essential health checks on the spacecraft must be completed. Then the eleven instruments on the orbiter and ten on the lander will be turned on and prepared for studying Comet 67P/Churyumov-Gerasimenko.

“We have a busy few months ahead preparing the spacecraft and its instruments for the operational challenges demanded by a lengthy, close-up study of a comet that, until we get there, we know very little about,” says Andrea Accomazzo, Rosetta operations manager.

Rosetta’s first images of 67P/Churyumov-Gerasimenko are expected in May, when the spacecraft is still 2 million km from its target. Towards the end of May, the spacecraft will execute a major maneuver to line up for its critical rendezvous with the comet in August.

After rendezvous, Rosetta will start with two months of extensive mapping of the comet’s surface, and will also make important measurements of the comet’s gravity, mass and shape, and assess its gaseous, dust-laden atmosphere, or coma. The orbiter will also probe the plasma environment and analyse how it interacts with the Sun’s outer atmosphere, the solar wind.

Using these data, scientists will choose a landing site for the mission’s 100 kg Philae probe. The landing is currently scheduled for November 11, 2014 and will be the first time that a landing on a comet has ever been attempted.

With almost negligible gravity from the comet’s 4 km-wide nucleus, Philae will have to use ice screws and harpoons to stop it from rebounding back into space after touchdown.

Among its wide range of scientific measurements, Philae will send back a panorama of its surroundings, as well as very high-resolution pictures of the surface. It will also perform an on-the-spot analysis of the composition of the ices and organic material, including drilling down to 23 cm below the surface and feeding samples to Philae’s on-board laboratory for analysis.

The focus of the mission will then move to the ‘escort’ phase, during which Rosetta will stay alongside the comet as it moves closer to the Sun, monitoring the ever-changing conditions on the surface as the comet warms up and its ices sublimate.

Rosetta will follow the comet throughout the remainder of 2015, as it heads away from the Sun and activity begins to subside.

You can read the team’s blog about the “wake up” here, and find out more about the Rosetta mission here.

Here’s a replay of the acquisition of signal:

Watch Live: ESA Waits for Signal from Comet-Chasing Spacecraft

Rosetta

Watch live streaming video from eurospaceagency at livestream.com

UPDATE: Rosetta woke up! Read our full story about the acquisition of signal here.

For the first time, a spacecraft will follow a comet as it approaches the Sun and land on its nucleus. But today is key to the success of the mission. After nearly two and a half years in hibernation, its time for Rosetta to wake up!

Rosetta has been soaring through the inner solar system for nearly a decade –flying past Mars and Earth several times and even briefly visiting a couple of asteroids. A special ‘hibernation mode’ for the spacecraft was designed by engineers to allow it to survive the large distances from the Sun during its cruise. Since it went into hibernation on June 9, 2011, Rosetta has orbited entirely on its own completely out of contact. But now the Rosetta spacecraft is finally entering the home stretch of its mission to orbit the 4-km-wide comet 67P/Churyumov-Gerasimenko.

Watch live, above, as mission controllers at ESA await for a signal from the spacecraft. The Rosetta mission control team at ESOC is expecting to receive the signal between 17:30-18:30 UTC.
Continue reading “Watch Live: ESA Waits for Signal from Comet-Chasing Spacecraft”

Wake Up, Rosetta!


It’s being called “the most important alarm clock in the Solar System” —  this 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. Using its thawed-out star trackers Rosetta will aim its transmitter towards Earth and, from 500 million miles (807 million km) away, will send a thumbs-up signal that everything is OK and it’s time to get back to work.

From that distance the transmission will take 45 minutes to reach us. Rosetta’s first signal is expected between 17:30 – 18:30 GMT (12:30 – 1:30 p.m. ET). Once we’re assured all is well, Rosetta has a very exciting year ahead!

After nearly a decade of soaring through the inner solar system, flying past Mars and Earth several times and even briefly visiting a couple of asteroids (2867 Steins on September 5, 2008 and 21 Lutetia on July 10, 2010) Rosetta is finally entering the home stretch of its mission to orbit the 4-km-wide comet 67P/Churyumov-Gerasimenko.

Once Rosetta enters orbit around the comet — the first time a spacecraft has ever done so — it will map its surface and, three months later in November, deploy the 220-lb (100-kg) Philae lander that will intimately investigate the surface of the nucleus using a suite of advanced science instruments. (Watch a video here of how all this will happen… using Legos!)

Read more: Spider-Like Spacecraft Aims To Touch A Comet Next Year After Rosetta Reactivates

With Philae firmly attached to the comet, Rosetta will follow it around the Sun as it makes its closest pass in August 2015 and then heads back out towards the orbit of Jupiter. Rosetta will provide the most detailed observations ever of a comet’s composition and dramatic evolution as it encounters the heat and energy of our home star.

Of course, before all this can happen Rosetta first has to… WAKE UP! It entered hibernation in July 2011 and has remained silent in a slow spin ever since, with only its computer and some heaters kept running. Waking up from a 31-month nap can’t be easy, so ESA is inviting people around the world to help Wake Up Rosetta (and possibly even win a trip to Germany for the landing in November) by sharing their short movies of how best to awaken a sleeping spacecraft and sharing them to the contest page on Facebook or to Twitter, Vine, or Instagram with the #WakeUpRosetta hashtag.

See more about the contest below:

Video submissions to the Wake Up Rosetta video contest will be accepted until 17:30 GMT on Monday so if you haven’t already, get your cameras out and your imaginations going… this spacecraft isn’t going to wake itself! (Well, actually it kinda is but you can still show off your creativity!)

And even if you don’t send in a video, you can watch the live feed of Monday’s events from ESA starting at 09:15 GMT (4:15 a.m. ET) here and here. (Also follow @ESA_Rosetta on Twitter — currently it’s “still sleeping.”)

Want to find out where Rosetta is right now? Check out this cool interactive map from Daniel Scuka, Senior Editor of Spacecraft Operations at ESOC.

Rosetta launched on March 2, 2004 by an Ariane-5 G+ from Europe’s spaceport in Kourou, French Guiana. Read more on the mission page and the Rosetta blog here.

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UPDATE Jan. 20: Rosetta has awoken! This afternoon at 18:18 UTC, after 48 minutes of increasingly tense anticipation, a signal from the spacecraft was received by both NASA’s Deep Space Network in Goldstone, CA and the ground station in Canberra, Australia. Rosetta is up and running and so far seems to be in good condition — Go Rosetta and Philae! Read the full story here.

Weekly Space Hangout – January 10, 2014: Wake Up, Rosetta! & Top Stories from AAS

Host: Fraser Cain
Guests: David Dickinson, Amy Shira Teitel, Scott Lewis, Brian Koberlein, special guest Ruth McAvinia from the ESA

This week’s stories:
Ruth:
Wake up, Rosetta!
Facebook link to contest

David:
AAS-Gamma Ray Gravitational Lens
AAS-Death by Black Hole
Antares Launch
Remote Deployment of Cubesats
Venus at Inferior Conjunction

Scott:
Learning tools for visually impaired:
More information on the 3-D Hubble images can be found here
Here’s the press release for the iBook being released
Frontier Fields

Brian:
New Triple Star System

Amy:
ISS Life extension

Fraser:
Space Ship 2’s first Supersonic Flight

We record the Weekly Space Hangout every Friday at 12:00 pm Pacific / 3:00 pm Eastern. You can watch us live on Google+, Universe Today, or the Universe Today YouTube page.

Can You Help Wake Up a Spacecraft?

On January 20, 2014 it will be time for the snoozing Rosetta spacecraft to awaken from 31 months of hibernation. Through an online contest, ESA has been looking for a little help in sending a wake-up call to the spacecraft, which will be 673 million kilometers from Earth. The “Wake Up Rosetta!” video contest has yielded some heartwarming, funny, and creative videos from families, school children and more. Here are a few of our favorites, and you can go to the contest’s Facebook page to find out how to submit your own video, as well as see more videos and vote for your favorite.

The top ten vote-getting videos will be transmitted out to Rosetta via one of ESA’s deep-space tracking stations, and there are additional prizes as well, including the top two video creators will be invited to the control center in Darmstadt, Germany for when the Philae lander attempts landing on comet 67P/Churyumov–Gerasimenko in November 2014 after latching on with a harpoon.

ESA themselves have come up with a video story of the Rosetta mission and how it will be awakened:

Find out more about Rosetta’s mission here, and the contest here.

Spider-Like Spacecraft Aims To Touch A Comet Next Year After Rosetta Reactivates

Watch out, you comet, Rosetta is on its way with a probe. The European Space Agency spacecraft is preparing to wake up in January from a nearly three-year-long hibernation period to ready for a close encounter with Comet 67P/Churyumov–Gerasimenko.

If all goes well, Rosetta should reach its destination in August and — after a couple of months in a mapping orbit — comes another exciting bit: the probe will deploy a spider-like lander called Philae on the surface in November. That will be the first time anything has soft-landed on a comet.

Philae has a ream of scientific instruments on board, most notably a drill that can penetrate as far as 20 centimeters (eight inches) into whatever lies below it. It can then pick up the samples and analyze them right on sight. This will allow the lander to learn more about what the comet’s surface and subsurface are made of, ESA says, and to figure out how its nucleus is constructed. (You can read more technical details here.)

A big concern, of course, is keeping Philae anchored on the low gravity of the comet (as was covered extensively in this past Universe Today story).

“As Philae touches down on the comet, two harpoons will anchor it to the surface; the self-adjusting landing gear will ensure that it stays upright, even on a slope, and then the lander’s feet will drill into the ground to secure it to the comet’s surface in the low gravity environment,” ESA wrote.

Artist's impression of the Rosetta spacecraft releasing its lander, Philae, above the surface of Comet 67P/Churyumov–Gerasimenko in November 2014. Credit: ESA–C. Carreau/ATG medialab
Artist’s impression of the Rosetta spacecraft releasing its lander, Philae, above the surface of Comet 67P/Churyumov–Gerasimenko in November 2014. Credit: ESA–C. Carreau/ATG medialab

But first comes Rosetta’s reactivation. ESA is so excited about this forthcoming milestone on Jan. 20 that it’s inviting the public to send in videos where people tell the spacecraft, essentially, to wake up after 31 months of hibernation. (The campaign is called “Wake Up, Rosetta”, and more contest details are here.)

What’s cute is that the official Rosetta Twitter account (@ESA_Rosetta) will become more exciting then as well. The last update, from Dec. 3, simply says “still sleeping” (as most of the updates do.) In response to someone asking the account to write something else this summer, the Twitter response was laconic: “A sleeping probe cannot tweet.”

But keep your eyes peeled even after the landing. Rosetta plans to stay with the comet as the icy body moves closer to the solar system, watching as the sun’s heat changes its surface. Read more about the mission here.

Could Juno’s Path Near Earth Uncover A Flyby Mystery?

Every so often, engineers send a spacecraft in Earth’s general direction to pick up a speed boost before heading elsewhere. But sometimes, something strange happens — the spacecraft’s speed varies in an unexpected way. Even stranger, this variation happens only during some Earth flybys.

“We detected the flyby anomaly during Rosetta’s first Earth visit in March 2005,” stated Trevor Morley, a flight dynamics specialist at the European Space Agency’s European Space Operations Centre in Darmstadt, Germany.

“Frustratingly, no anomaly was seen during Rosetta’s subsequent Earth flybys in 2007 and 2011. This is a real cosmic mystery that no one has yet figured out.”

The phenomenon has been noticed in several spacecraft (both from ESA and NASA) since 1990. NASA’s NEAR asteroid spacecraft in January 1998 had the largest change, of 13 millimeters (0.5 inches) a second. The smallest variations, with NASA’s Saturn-bound Cassini in 1999 and Mercury-pointing MESSENGER in 2005, were below the threshold of measurement.

ESA won’t even speculate on what’s going on. “The experts are stumped,” the agency says in a press release.

Those experts, however, do have some ideas on how to track that down. ESOC plans to watch Juno’s flyby using a 35 meter deep-space dish in Malargüe, Argentina, as well as a 15-meter dish in Perth, Australia

“The stations will record highly precise radio-signal information that will indicate whether Juno speeds up or slows down more or less than predicted by current theories,” ESA states.

What do you think is going on? Let us know in the comments!

Source: European Space Agency

Can We Land On a Comet?

The Rosetta mission will do something never before attempted: land on a comet. The spacecraft is now on its way to intercept comet 67P/Churyumov-Gerasimenko in January 2014 and land a probe on it for what promises to be an amazing view. But what we know of comets so far comes from a few flyby missions. So, with surface composition and conditions largely a mystery, so how did engineers prepare to land on something that could be either solid ice or rock, or a powdery snow or regolith – or something in between?

They had to design the Philae lander so it could land equally well on any surface. In the tiny gravitational field of a comet, landing on hard icy surface might cause Philae to bounce off again. Alternatively, hitting a soft snowy one could result in it sinking. To cope with either possibility, Philae will touch as softly as possible. In fact, engineers have likened it more to docking in space.

Philae will fire harpoons to secure itself to the comet; additionally, the landing gear is equipped with large pads to spread its weight across a broad area (kind of like snowshoes.)

While landing on a comet will certainly be nail-biting, having a front row seat for when the comet gets closer to the Sun is the most highly anticipated part of the mission.

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“In some ways, a flyby is just a tantalizing glimpse of a comet at one stage in its evolution,” says Claudia Alexander, project scientist for the U.S. Rosetta Project at JPL. “Rosetta is different. It will orbit 67P for 17 months. We’ll see this comet evolve right before our eyes as we accompany it toward the Sun and back out again.”

We’ll be able to watch as it becomes “something poetic and beautiful, trailing a vast tail,” said Alexander. For once, we’ll be able to watch the surface of a comet transform in front of our eyes instead of relying on artist concept drawings! Additionally, the Rosetta spacecraft up above will be busy mapping the comet’s surface and magnetic field, monitoring the comet’s erupting jets and geysers, measuring outflow rates, and much more. Together, the orbiter and lander will build up the first 3-D picture of the layers and pockets under the surface of a comet.

Comets are considered a gold mine for astronomers who want to know what conditions were like back in the early days of our Solar System. And the data and images from this mission promises to be some of the most stunning we’ve yet seen.

Find out more about the Rosetta mission in the accompanying video, or see the ESA Rosetta website.

Source: [email protected]

Asteroid Lutetia May Have A Molten Core

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Way out in space, 282 million miles from home, the intrepid ESA Rosetta spacecraft is still busy, but had time to send us an unprecedented view of ancient asteroid Lutetia. On July 10, 2010, Rosetta flew past Lutetia and the results of the imaging revealed surface features which point to an astonishing history. This particular asteroid might not have a “heart of gold”, but it may very well have – or had – a molten interior.

Buzzing by at a speed of 54 000 km/hr and a closest distance of 3170 km, Rosetta took a series of high resolution images and returned them to an international team of researchers from France, Germany, the Netherlands and the United States. By closely examining the craters, cracks and surface, the team was able to determine that Lutetia survived a multitude of impacts – yet retained much of its original structure.

Lutetia fly-by from Science News on Vimeo.

Benjamin Weiss, an associate professor of planetary sciences in MIT’s Department of Earth, Atmospheric and Planetary Sciences, reports Lutetia may have a molten core and this finding shows a “hidden diversity” for known structures within the greater asteroid belt.

“There might be many bodies that have cores and interesting interiors that we never noticed, because they’re covered by unmelted surfaces,” says Weiss, who is a co-author on both Science papers and lead author for the paper in PSS. “The asteroid belt may be more interesting than it seems on the surface.”

Although the encounter was brief, images from the OSIRIS camera revealed some surface features which are believed to be up to 3.6 billion years old – while others appear to be 50-80 million. These ages can be estimated through impact events and the amount and distribution of ejecta. Some of the areas on Lutetia are heavily cratered, implying greater age, while others appear to be landslide events perhaps caused by nearby fractures. While most asteroids are small, light, and have smooth surfaces – Lutetia is different. It appears to be dense, yet relatively porous… a finding that points toward a “dense metallic core, with a once melted interior underneath its fractured crust.”

“We don’t think Lutetia was born looking like this,” says Holger Sierks, of the Max-Planck-Institut für Sonnensystemforschung, Lindau, Germany. “It was probably round when it formed.”

You’ve got to hand it to Rosetta. By being able to study these images, the many teams of scientists now have evidence for a theory developed last year by Weiss, Elkins-Tanton and MIT’s Maria Zuber. By studying chondrite meteorites, they’ve speculated these strongly magnetized samples most likely occurred in an asteroid with a melted, metallic core. If this theory proves to be correct, the Lutetia simply managed to dodge the proverbial bullets and developed with a molten interior.

“The planets … don’t retain a record of these early differentiation processes,” Weiss says. “So this asteroid may be a relic of the first events of melting in a body.”

According to MIT news, Erik Asphaug, a professor of planetary science at the University of California at Santa Cruz, studies “hit-and-run” collisions between early planetary bodies. He says the work by Weiss and his colleagues is a solid step toward resolving how certain asteroids like Lutetia may have evolved.

“We’ve had decades of cartoon speculation, and here’s speculation that’s anchored in physical understanding of how the interiors of these bodies would evolve,” says Asphaug, who was not involved in the research. “It’s like getting through the first 100 pages of a novel, and you don’t know where it’s leading, but it feels like the beginnings of a coherent picture.”

Another Rosetta stone?

Original Story Sources: ESA News Release and MIT News Release.