Comet-Bouncing Philae Spacecraft Caught On Camera In Newly Enhanced Images

A still of the Philae spacecraft bouncing off Comet 67P/Churyumov–Gerasimenko in an animation of Rosetta spacecraft images. The image was taken Nov. 12, 2014 at 10:35 a.m. EDT (3:35 p.m. UTC). Credit: ESA/Rosetta/NAVCAM; pre-processed by Mikel Canania

When the Philae lander arrived at its target comet last week, the little spacecraft landed three times in two hours before coming to a rest. While controllers could see this information from data coming in, they didn’t have any photographic proof — until now.

The animation above, an enhancement of images from the orbiting Rosetta spacecraft released late last week, show Philae and its shadow –mid-bounce! — very shortly after landing on Wednesday (Nov. 12). Philae’s first jump lasted nearly two hours before it took off again, flew for another few minutes, and landed in a shady spot where its batteries drained on Friday.

Here’s another cool thing about these images — some of the credit to Philae’s discovery comes through crowdsourcing! This is what the European Space Agency’s Rosetta blog said about who found this:

Credit for the first discovery goes to Gabriele Bellei, from the interplanetary division of Flight Dynamics, who spent hours searching the NAVCAM images for evidence of the landing.

Once the images were published, blog reader John Broughton posted a comment to report that he had spotted the lander in them (thank you, John). There was also quite some speculation by Rosetta blog readers in the comments section, wondering which features might be attributable to the lander. Martin Esser, Henning, and Kasuha in particular were among the first to make insightful observations on the topic, although many others have since joined in.

Last but not least, a careful independent review of the images was made by Mikel Catania from the earth observation division of Flight Dynamics, with the same conclusion. He also made the annotated animation shown here.

This goes to show you that while there is disappointment that Philae is in a long (perhaps permanent) sleep sooner than scientists hoped, data from the spacecraft will continue to be analyzed in the coming months and years. And don’t forget that the orbiting Rosetta spacecraft is in good health and will continue to return data on 67P as it draws closer to the Sun through 2015.

A still of the Philae spacecraft bouncing off Comet 67P/Churyumov–Gerasimenko in an animation of Rosetta spacecraft images. The image was taken Nov. 12, 2014 at 10:35 a.m. EDT (3:35 p.m. UTC). Credit: SA/Rosetta/NAVCAM; pre-processed by Mikel Catania
A still of the Philae spacecraft bouncing off Comet 67P/Churyumov–Gerasimenko in an animation of Rosetta spacecraft images. The image was taken Nov. 12, 2014 at 10:35 a.m. EDT (3:35 p.m. UTC). Credit: SA/Rosetta/NAVCAM; pre-processed by Mikel Catania

Alone and Confused, Philae Breaks our Hearts

The Philae that could! The lander photographed during its descent by Rosetta. Credit: ESA/Rosetta/MPS for Rosetta Team/

I was twelve years old when Columbia disintegrated. Space exploration was not even a particular interest of mine at the time, but I remember exactly where I was when the news came.  My dad and I were sitting in the living room of my childhood home, listening to NPR. I don’t really recall how I felt when they broke into our program with the news, but I remember well the two emotions that seemed to permeate the coverage that soon become constant: confusion and sadness. As I watched the almost surreal saga of ESA’s Philae this week, I found my mind wandering back to that day eleven years ago. That confusion rang out was hardly surprising; after all, things weren’t going right and we didn’t know why. But it was the sadness, I think, that drew my mind into the past. Many of the countless people watching Philae’s distress unfold before us weren’t merely disappointed that a decades-in-the-making experiment wasn’t going as planned. The word heartbroken kept springing to mind.

Let me be unequivocal: the loss of a machine, no matter how valuable or beloved, pales in comparison to the forfeit of human life. The astronauts lost on Columbia, like those snatched from us before and since, left behind families, friends, and a grateful world. But, why, then, did it seem to feel so similar to so many people?

 “This is legitimately upsetting” a friend and colleague texted me on Friday as it became clear that the tiny lander’s batteries were beginning to run dry. She was far from alone in her sentiment. Across Twitter, people from around the world seemed to be lashing out against the helplessness of the situation.

https://twitter.com/asamsaktha/status/533700062673928193

And, in conversations I had with other scientists at the 46th annual Division for Planetary Sciences meeting in Tucson, AZ this week, people seemed almost mournful at the prospect of the lander’s loss. These same researchers had laughed and cheered just days earlier when shown the crater made by NASA’s LADEE spacecraft upon its crash into the lunar surface.

 The questions in my mind are numerous. What’s the cause of this inequity? Why do we seem to latch onto certain spacecraft and blithely ignore others? What is it that makes us become emotionally attached to machines in the first place? 

In part, I think, our attachment comes from the unprecedented view offered to us by social media. In 1990, an event not so dissimilar from this one beset NASA’s Galileo spacecraft. Flying by the Earth on its way to Jupiter, Galileo had just attempted to unfurl its main antenna, a maneuver critical to the mission’s success.  In mission control, they received the bad news: the antenna was stuck. But, the world did not break down in despair. In the days to come, stories would appear in newspapers and on the nightly news, but a world where even email was in its infancy lacked a means for the average citizen to follow along with every detail. 

Nineteen years later, this would not be the case. As soon as it became clear to those in ESA headquarters that something had gone very wrong during Philae’s descent, we all knew. And, as data began to trickle in about one bounce off the surface and then another, we all cringed. When the last power drained from the lander’s batteries, we followed along, one volt after another. Philae may have been the pride of the ESA scientists and engineers who designed it, but it felt like it was ours. 

But, it didn’t feel like ours in the way that a car or a plane or even a space station does. It felt like our friend. No doubt, this can be directly linked to the first person point of view employed for its Twitter account. Instead of the @Phillae2014 account reporting “the Ptolemy instrument has made a measurement,” we get “I just completed a @Philae_Ptolemy measurement!!” It seems like a small change, but it opens up a whole new world of connection with this distant traveler. At no time was this clearer than when things started to go wrong.

 How poignant is that? Two travelers talking to one another from across the solar system. But, as Philae’s time began to wind down, the messages tugged even more urgently on our heartstrings.

And, it all pales in comparison to the way China’s Yutu rover signed off when it looked like a malfunction might cause it to freeze to death on the Moon (original Chinese, CNN translation):

… my masters discovered something abnormal with my mechanical control system. …I’m aware that I might not survive this lunar night…

The sun has fallen, and the temperature is dropping so quickly… to tell you all a secret, I don’t feel that sad. I was just in my own adventure story – and like every hero, I encountered a small problem.

Goodnight, Earth. Goodnight, humanity.

Talk about heartbreaking.

This personal point of view combines particularly effectively with landers and rovers. These craft seem more human than ships like Cassini or Galileo, with their silent glide through deep space. When something goes wrong with a surface explorer, as it did with Philae or Yutu, it plays on our deepest fears. Every time we’re lost, the little voice of panic begins to creep into our thoughts: “what if this is the time that I can’t get back?” Reading the “thoughts” of a tiny spacecraft, lost and alone and confused, puts us right there ourselves. As mission controllers edged towards desperation in their attempts to save the stricken explorer, we knew how that delirious urgency felt. Our attachment becomes almost unavoidable. 

So, what does this all mean? I think it’s a clear signal that people are engaged by the exploration of space. When it comes to us in the right way, on our terms, it’s a big hit. By anthropomorphizing these robots, we humanize the science that they do. Suddenly a machine more than 500 million kilometers away becomes more relatable than the scientists next door who control it. Perhaps ESA, NASA, and other space agencies can extend this relationship even further. Rather than springing to “life” upon liftoff, spacecraft can share with us their view of the entire process, starting not from space, but from the first drawings on an engineer’s blackboard.

One thing’s for sure, though. A relationship like that won’t make times like these any easier to handle.

Can Philae Power Up After Doing A Triple Comet Landing Into Shadowy Spot?

First photo released of Comet 67P/C-G taken by Philae during its descent. The view is just 1.8 miles above the comet. Credit: ESA

Update, 10 p.m. EST: Philae is now asleep, according to the European Space Agency, for what could prove to be a long nap (at the least). It’s in “idle mode” with depleted batteries, and little sunlight to gain energy. For more information, check out this ESA blog post.

There’s power problems looming for the Philae probe after it made not one, not two, but three landings on 67P/Churyumov–Gerasimenko this Wednesday. The primary battery that the lander is using right now for its primary mission (a few days) is expected to run out in less than a day. As for surface comet observations for the next several months … that’s now in doubt.

Philae was supposed to touch down in a spot that provided seven hours of illumination per day on the comet (with a “day” there being 12.4 hours). But after doing a hop, skip and leap on the surface, the lander is now nestled in a spot that provides only 1.5 hours of sunlight daily to recharge the solar panels. “There is an impact on the energy budget to conduct science for a longer period of time,” the European Space Agency warned in a blog post.

Philae (and its parent craft Rosetta, which is in good health and will observe the comet from orbit through at least part of 2015) went sailing through space for more than a decade before Philae successfully touched down on the surface. After early telemetry came through showing harpoons had fired to secure the lander on 67P, more detailed information showed the harpoons had failed to fire. And this led to an incredible journey.

After touching down about where it was supposed to — controllers know this based on its descent camera and previous images from the Rosetta spacecraft — Philae then lifted off again and floated for nearly two hours. This is possible due to the extremely low gravity field on the comet, which had it drifting gently for one hour and 50 minutes.

First panorama sent by Philae from the surface of the comet. At upper right we see the reflection of the Sun and the top of the  CONSERT instrument antenna. Credit: ESA
First panorama sent by Philae from the surface of the comet. At upper right we see the reflection of the Sun and the top of the CONSERT instrument antenna. Credit: ESA

Philae travelled about one kilometer (0.62 miles) in this time before brushing the surface. Then it began another seven-minute journey before settling down in its current location. Exactly where is not known.

“Preliminary data from the CONSERT experiment suggest that Philae could have travelled closer to the large depression known as Site B, perhaps sitting on its rim. High-resolution orbiter images, some of which are still stored on Rosetta, have yet to confirm the location,” the European Space Agency wrote in a blog post.

“The lander remains unanchored to the surface at an as-yet undetermined orientation. The science instruments are running and are delivering images and data, helping the team to learn more about the final landing site.”

So far, the team knows that the area has dust and other stuff covering the surface, and a panoramic image released yesterday suggests that at least one of the lander’s three feet is “in open space.”

Source: European Space Agency

Music to Celebrate the Rosetta Mission

We report on the Rosetta mission to share the news and follow the progress of the precarious-perched Philae. But sometimes it takes another form of communication to dig down deep and release the wonder we all feel inside at the amazing images that daily light up our monitors. Music. Inspired by the Rosetta mission and in celebration of it, Vangelis composed three pieces of music set to slide shows featuring beautiful imagery of comet 67P/C-G and Philae.  Continue reading “Music to Celebrate the Rosetta Mission”

New Images from Philae Reveal Comet’s Ancient Surface

First panorama sent by Philae from the surface of the comet. At upper right we see the reflection of the Sun and the top of the CONSERT instrument antenna. Credit: ESA

We may not know exactly where Philae is, but it’s doing a bang-up job sending its first photos from comet 67P/Churyumov-Gerasimenko. After bouncing three times on the surface, the lander is tilted vertically with one foot in open space in a “handstand” position.  When viewing the photographs, it’s good to keep that in mind. 

Philae landed nearly vertically on its side with one leg up in outer space. Here we see it in relation to the panoramic photos taken with the CIVA cameras. Credit: ESA
Philae landed nearly vertically on its side with one leg up in outer space. Here we see it in relation to the panoramic photos taken with the CIVA cameras. Credit: ESA

Although it’s difficult to say how far away the features are in the image. In an update today at a press briefing, Jean Pierre Biebring, principal investigator of CIVA/ROLIS (lander cameras), said that the features shown in the frame at lower left are about 1-meter or 3 feet away. Philae settled into its final landing spot after a harrowing first bounce that sent it flying as high as a kilometer above the comet’s surface.

After hovering for two hours, it landed a second time only to bounce back up again a short distance – this time 3 cm or about 1.5 inches. Seven minutes later it made its third and final landing. Incredibly, the little craft still functions after trampolining for hours!

Stephan Ulamec, Philae Lander manager, describes how Philae first landed less than 100 meters from the planned Agilkia site (red square). Without functioning harpoons and thrusters to fix it to the ground there, it rebounded and shot a kilometer above the comet. Right now, it's somewhere in the blue diamond. Credit: ESA
Stephan Ulamec, Philae Lander manager, describes how Philae first landed less than 100 meters from the planned Agilkia site (red square). Without functioning harpoons and thrusters to fix it to the ground there, it rebounded and shot a kilometer above the comet. Right now, it’s somewhere in the blue diamond. Credit: ESA

Despite its awkward stance, Philae continues to do a surprising amount of good science. Scientists are still hoping to come up with a solution to better orientate the lander. Their time is probably limited. The craft landed in the shadow of a cliff, blocking sunlight to the solar panels used to charge its  battery. Philae receives only 1.5 hours instead of the planned 6-7 hours of sunlight each day. That makes tomorrow a critical day.  Our own Tim Reyes of Universe Today had this to say about Philae’s power requirements:

Rosetta’s lander Philae is safely on the surface of Comet 67P/Churyumov-Gerasimenko, as these first two CIVA images confirm. One of the lander’s three feet can be seen in the foreground. The image is a two-image mosaic. Credit: ESA/Rosetta/Philae/CIVA
One of the lander’s three feet can be seen in the foreground in this high-resolution two-image mosaic. Credit: ESA/Rosetta/Philae/CIVA

“Philae must function on a small amount of stored energy upon arrival: 1000 watt-hours (equivalent of a 100 watt bulb running for 10 hours). Once that power is drained, it will produce a maximum of 8 watts of electricity from solar panels to be stored in a 130 watt-hour battery.” You can read more about Philae’s functions in Tim’s recent article.

Ever inventive, the lander team is going to try and nudge Philae into the sunlight by operating the moving instrument called MUPUS tonight. The operation is a delicate one, since too much movement could send the probe flying off the surface once again.

Here are additional photos from the press conference showing individual segments of the panorama and other aspects of Philae’s next-to-impossible landing. As you study the crags and boulders, consider how ancient this landscape is. 67P originated in the Kuiper Belt, a large reservoir of small icy bodies located just beyond Neptune, more than 4.5 billion years ago. Either through a collision with another comet or asteroid, or through gravitational interaction with other planets, it was ejected from the Belt and fell inward toward the Sun.

Astronomers have analyzed its orbit and discovered that up until 1840, the future comet 67P never came closer than 4 times Earth’s distance from the Sun, ensuring that its ices remained as pristine as the day they formed. After that date, the comet passed near Jupiter and its orbit changed to bring it within the inner Solar System. We’re seeing a relic, a piece of dirty ice rich with history. Even a Rosetta stone of its own we can use to interpret the molecular script revealing the origin and evolution of comets.

Philae falls to the craggy comet photographed by the Rosetta mothership. Credit: ESA
Philae falls to the craggy comet photographed by the Rosetta mothership. Credit: ESA
An image of Comet 67P/Churyumov–Gerasimenko at less than 10 km from its surface. This selection of previously unpublished ‘beauty shots’, taken by Rosetta’s navigation camera, presents the varied and dramatic terrain of this mysterious world from this close orbit phase of the mission. Credit: ESA.
An image of Comet 67P/Churyumov–Gerasimenko at less than 10 km from its surface. This selection of previously unpublished ‘beauty shots’, taken by Rosetta’s navigation camera, presents the varied and dramatic terrain of this mysterious world from this close orbit phase of the mission. Credit: ESA.
Frame from panoramic image. Credit: ESA
Frame from panoramic image. This has been heavily toned to reveal details in the shadow of the cliff. Credit: ESA
Frame from panoramic image. Credit: ESA
Frame from panoramic image. Credit: ESA
Frame from panoramic image. Credit: ESA
Frame from panoramic image. Credit: ESA
Frame from panoramic image. Credit: ESA
Frame from panoramic image. Credit: ESA
Frame from panoramic image. Credit: ESA
Frame from panoramic image. Credit: ESA
Image from the Philae lander as it approached the surface. The dust-covered boulder at upper right is about 5 meters (16.4 feet) across. The dust might have originated through vaporization of ice on the boulder itself or deposited there by dust settling from jets elsewhere.  Credit: ESA
Image from the Philae lander as it approached the surface. The dust-covered boulder at upper right is about 5 meters (16.4 feet) across. The dust might have originated through vaporization of ice in the boulder itself or settled there from active jets elsewhere on the comet. Credit: ESA

 

Philae’s First Photos; Update on its Troubled Landing

Image from the Philae lander as it approached the surface. The dust-covered boulder at upper right is about 5 meters (16.4 feet) across. The dust might have originated through vaporization of ice on the boulder itself or deposited there by dust settling from jets elsewhere. Credit: ESA
First photo released of Comet 67P/C-G taken by Philae during its descent. The view is just 1.8 miles above the comet. Credit: ESA
First photo released of Comet 67P/C-G taken by Philae during its descent. The view is just 1.8 miles above the comet. Credit: ESA

Hey, we’re getting closer! This photo was taken by Philae’s ROLIS instrument just 1.8 miles (3 km) above the surface of 67P/Churyumov-Gerasimenko at 8:38 a.m. (CST) today. The ROLIS instrument is a down-looking imager that acquires images during the descent and doubles as a multi-wavelength close-up camera after the landing. The aim of the ROLIS experiment is to study the texture and microstructure of the comet’s surface. ROLIS (ROsetta Lander Imaging System) is a descent and close-up camera on the Philae lander.

I know, I know. You got a fever for more comet images the way Christopher Walken on Saturday Night Live couldn’t get enough cowbell.

Just to give you a flavor for the rugged landscape Philae was headed toward earlier today, this photo was taken by Rosetta at an altitude of 4.8 miles (7.7 km) from the comet's surface. Credit: ESA
Just for a little flavor of the rugged landscape Philae was headed toward earlier today, this photo was taken recently by Rosetta 4.8 miles (7.7 km) from the comet’s surface. Credit: ESA

Key scientists in a  media briefing this afternoon highlighted the good news and the bad news about the landing. We reported earlier that both the harpoons and top thrusters failed to fire and anchor the lander to the comet. Yet land it did – maybe more than once! A close study of the data returned seems to indicate that Philae, without its anchors, may have touched the surface and then lifted off again, turning itself from the residual angular momentum left over after its flywheel was shut down.  Stephan Ulamec, Philae Landing Manager, got a appreciative laugh from the crowd when he explained it this way:  Maybe today we didn’t just land once. We landed twice!”

Stephan Ulamec, Philae Lander Manager. Credit: ESA
Stephan Ulamec, Philae Lander Manager. Credit: ESA

Telemetry from the probe has been sporadic. Data streams come in strong and then suddenly cut out only to return later. These fluctuations in the radio link obviously have the scientists concerned and as yet, there’s no explanation for them. Otherwise, Philae landed in splendid fashion almost directly at the center of its planned “error ellipse”.

Instruments on Philae are functioning normally and gathering data as you read this.  Ulamec summed up the situation nicely:  “It’s complicated to land and also complicated to understand the landing.”

Scientists and mission control will work to hopefully resolve the harpoon and radio link issues. The next live webcast begins tomorrow starting at 7 a.m. (CST). Although nothing definite was said, we may see more images arriving still today, so stop by later.

We Land on a Comet Today! Updates on Philae’s Progress

Just released "farewell photo" taken by the Philae lander as it departed Rosetta around 2:30 a.m. (CST) today. It shows the one of the solar arrays. Credit: ESA/Rosetta/Philae/CIVA

Anticipation is intense as the Philae lander free-falls to the surface of Comet Churyumov-Gerasimenko this morning. The final “Go” for separation from the Rosetta spacecraft was given around 2:30 a.m.; Philae’s now well on its way to Agilkia, the target landing site atop the 67P/C-G’s largerEverything is running smoothly except for one potential problem. During checks on the lander’s health, it was discovered that the active descent system, which provides a thrust to avoid rebound at the moment of touchdown, can’t be activated.

Artist impression of Philae separating from Rosetta earlier this morning. The lander is now free-falling to the comet under the influence of its gravity. Credit: ESA
Artist impression of Philae separating from Rosetta earlier this morning. The lander is now free-falling to the comet under the influence of its gravity. Credit: ESA

At touchdown, as Philae anchors itself to the comet with harpoons and ice screws on each of its legs, the thruster on top of the lander is supposed to push it down to counteract the force of the harpoon firing in the opposite direction.

Klim Churyumov (left) Svetlana Gerasimenko are both at ESA today during the historic landing on the comet they discovered on September 20, 1969. Credit: ESA TV
Klim Churyumov (left) Svetlana Gerasimenko are both at ESA today during the historic landing on the comet they discovered on September 20, 1969. Credit: ESA TV

“The cold gas thruster on top of the lander does not appear to be working so we will have to rely fully on the harpoons at touchdown,”says Stephan Ulamec, Philae Lander Manager at the DLR German Aerospace Center.

The Philae that could! The lander photographed during its descent by Rosetta. Credit: ESA/Rosetta/MPS for Rosetta Team/
The Philae that could! The lander photographed during its descent by Rosetta. Credit: ESA/Rosetta/MPS for Rosetta Team/

Philae is on target to land on the comet around 9:37 a.m. CST (15:37 UT). Confirmation of touchdown will take about 28 minutes as the signal, traveling at the speed of light, works its way back on Earth. As Philae floats down to the comet it not only has to deal with the 67P/C-G’s gravity but also the cloud of dust and ice grains escaping from the surface. Check back for regular updates and photos!

Tense control room during the  Philae landing confirmation. Credit: ESA
Tense control room during the Philae landing confirmation Time: 9:48 a.m. CST. Credit: ESA

Philae Ready to Take Flying Leap to Historic Comet Landing (Coverage Information)

After a ten year journey that began with the launch from the jungles of French Guyana, landing Philae is not the end of mission, it is the beginning of a new phase. A successful landing is not guaranteed but the ESA Rosetta team is now ready to release Philae on its one way journey. (Photo Credits: ESA/NASA, Illustration: J.Schmidt)

We are now in the final hours before Rosetta’s Philae lander is released to attempt a first-ever landing on a comet. At 9:03 GMT (1:03 AM PST) on Wednesday, November 12, 2014, Philae will be released and directed towards the surface of comet 67P/Churyumov–Gerasimenko. 7 hours later, the lander will touch down.

Below you’ll find a timeline of events, info on how to watch the landing, and an overview of how the landing will (hopefully) work.

In human affairs, we build contingencies for missteps, failures. With spacecraft, engineers try to eliminate all single point failures and likewise have contingency plans. The landing of a spacecraft, be it on Mars, Earth, or the Moon, always involves unavoidable single point failures and points of no return, and with comet 67P/Churyumov–Gerasimenko, Rosetta’s Philae lander is no exception.

Rosetta’s and Philae’s software and hardware must work near flawlessly to give Philae the best chance possible of landing safely. And even with flawless execution, it all depends on Philae’s intercepting a good landing spot on the surface. Philae’s trajectory is ballistic on this one way trip to a comet’s surface. It’s like a 1 mile per hour bullet. Once fired, it’s on its own, and for Philae, its trajectory could lead to a pristine flat step or it could be crevasse, ledge, or sharp rock.

Live European Space Agency Coverage also Main Page Live Feed

Watch ESA’s live feed:

The accuracy of the landing is critical but it has left a 1 square kilometer of uncertainty. For this reason, engineers and scientists had to survey the whole surface for the most mild features. Comet 67P has few areas that are not extreme in one way or another. Site J, now called Agilkia, is one such site.

When first announced in late September, the time of release was 08:35 GMT (12:35 AM PST). Now the time is 9:03 GMT. The engineers and computer scientists have had six weeks to further refine their trajectory. It’s a complicated calculation that has required running the computer simulation of the descent backwards. Backwards because they can set a landing time then run Philae backwards to the moment of release. The solution is not just one but many, thousands or millions if you want to look in such detail. With each release point, the engineers had to determine how, or if, Rosetta could be navigated to that coordinate point in space and time.

Arrival time of the radio signal with landing status: 16:30 GMT

Rosetta/Philae at 500 million km [320 million miles], 28.5 minutes light time

Arrival of First Images: 06:00 GMT, November 13, 2014

The gravity field of the comet is so weak, it is primarily the initial velocity from Rosetta that delivers Philae to the surface. But the gravity is there and because of the chaotic shape and unknown (as yet) mass distribution inside, the gravity will make Philae move like a major league knuckleball wobbling to the plate and a batter. Furthermore, the comet during the  seven hour trip will make half a rotation. The landing site will not be in site when Philae is released.

And as Philae is on final approach, it will use a small rocket not to slow down but rather thrust it at the comet, landing harpoons will be fired, foot screws will try to burrow into the comet, and everyone on Earth will wait several minutes for a message to be relayed from Philae to Rosetta to the Deep Space Network (DSN) antennas on Earth. Philae will be on its own as soon as it leaves Rosetta and its fate is a few hours away.

Why travel to a comet? Comets represent primordial material leftover from the formation of the solar system. Because cometary bodies were formed and remained at a distance from the heat of the sun, the materials have remained nearly unchanged since formation, ~4.5 billion years ago. By looking at Rosetta’s comet, 67P/Churyumov–Gerasimenko, scientists will gain the best yet measurements of a comet’s chemical makeup, its internal structure created during formation, and the dynamics of the comet as it approaches the warmth of the Sun. Theories propose that comets impacting on Earth delivered most of the water of our oceans. If correct, then we are not just made of star-stuff, as Carl Sagan proclaimed, we are made of comet stuff, too. Comets may also have delivered the raw organic materials needed to start the formation of life on Earth.

Besides the ESA live feeds, one can take a peek at NASA’s Deep Space Network (DSN) at work to see which telescopes are communicating with Rosetta. JPL’s webcast can watched below:



Broadcast live streaming video on Ustream

Past Universe Today Articles on the Rosetta Mission:

A Comet’s Tale – Rosetta’s Philae, Five Days from Touchdown
Stinky! Rosetta’s Comet Smells Like Rotten Eggs And Ammonia
Why Watch ESA Rosetta’s Movie ‘Ambition’? Because We Want to Know What is Possible
Rosetta’s Philae Lander: A Swiss Army Knife of Scientific Instruments
ESA’s Rosetta Mission sets November 12th as the Landing Date for Philae
Creepy Comet Looms In The Background Of Newest Philae Spacecraft Selfie
How Do You Land on a Comet? Very Carefully.
How Rosetta Will Send Philae Lander To Comet’s Surface (Plus, Landing Site Contest!)
Spider-Like Spacecraft Aims To Touch A Comet Next Year After Rosetta Reactivates
Rosetta’s Comet Springs Spectacular Leaks As It Gets Closer To The Sun
How Dust Lightens Up The ‘Dark Side’ Of Rosetta’s Comet
It’s Alive! Rosetta’s Comet Flares As It Approaches The Sun

References:

Why visit a comet, University of Leicester, Planetary Scientist explains

A Comet’s Tale – Rosetta’s Philae, Five Days from Touchdown

Rosetta, the scientific mission to explore a comet's surface. "Ambition", a short Sci-Fi film, set in the near future, and Rosetta, the children's fable, to encourage the next generations to undertake on the great adventures still to come. (Photo Credits: ESA, Platige Image, ESA Communications)

In the recently released Rosetta short film called “Ambition”, the master begins a story to his apprentice – “Once upon a time.” The apprentice immediately objects to his triteness. But he promises that it is worth the slight tribulation. Who could have imagined ten years ago that Rosetta would become so successful in two such contrasting approaches to telling a tale.

The Rosetta mission is part franchise and part scientific mission. In five days, Rosetta will reach a crossroad, a point of no return as epic as moments in Harry Potter or Lord of the Rings. A small mindless little probe called Philae will be released on a one-way trip to the surface of a comet. Win or lose, Philae will live on in the tale of a comet and a mission to uncover the mysteries of our planet’s formation.

ESA did not promise a good mission as Aidan Gillen promises a good story in Ambition. A space mission is never put in terms of a promise but rather it is thousands of requirements and constraints that formulate a mission plan and a spacecraft design. The European Space Agency put 1 billion Euros ($1.3 billion) to work and did so in what now looks like one of the greatest space missions of the first century of space exploration.

The Rosetta mission is actually two missions in one. There is the comet chaser, the orbiter – Rosetta and then the lander Philae. The design of Rosetta’s objectives is some part, probably in large part, was conceived by dismissing the presence of Philae. Make a space probe to a comet that just orbits the small body. Select your scientific instrumentations accordingly. Now add a small lander to the mission profile that will do something extraordinary – what Rosetta cannot do with its instrumentation. Finally, make sure that Rosetta has everything needed to support Philae’s landing on a comet.

Here is what they have as the game plan on November 12th (the sequence of events begins while its still November 11th in the Americas). These two times are absolutely non- trivial. They are finely tuned to a timepiece called  67P/Churyumov–Gerasimenko. If calculations were made in error, then Philae’s ultimate fate is unknown. Start exactly on time and Philae will be given the best chance at making a successful  touchdown on the comet.

Separation of Philae from Rosetta:   09:03 GMT (10:03 CET)

Touchdown on the comet:                    16:02 GMT (17:02 CET).

During this time, comet  67P/Churyumov–Gerasimenko will complete over half a rotation on its axis. To be exact, it will rotate 56.2977% of a full rotation. Comet 67P will have its back turned towards Rosetta as it holds the diminutive Philae for the last time and releases Philae for the first and only time.

Now that the ESA, with help from the graphic artists from Platige Image from Poland, has released something entertaining for the science fiction minded among us, they have again released a next episode in their children’s fable of Rosetta and Philae (video below). This cartoon of the final moments of Rosetta and Philae together preparing for the descent which could well be the final moments of Philae.

Philae could fail, crack like an egg on a sharp rock or topple over a cliff or into a crevasse on the surface of 67P. What happens to Philae will make for a Grimm’s fairy tale ending or something we would all prefer. In either case, the ESA is using graphic arts and storytelling to inspire the next generations to join in what our JFK called “great adventures of all time” [ref].

Through a contest something NASA and JPL have used several times to involve the public, the ESA asked the public to come up with a name for the landing site, site J. Out of the thousands of entries, 150 people suggested the name Agilkia [ref]. Alexandre Brouste from France, the designated winner, has been invited to watch the landing activities at Rosetta’s mission control in Darmstadt, Germany. It follows from the Eqyptian theme of the mission’s two probes. “Rosetta” comes from the clay tablet discovered in the 1800s that led to the deciphering of Egyptian hieroglyphics. Philae” is a island on the Nile which held magnificent Eqyptian temples. With the operation  of the Aswan dam starting in 1902, the island of Philae was repeatedly flooded and the temple was at risk. UNESCO beginning in 1960 started a project to save the islands historic structures. They were all moved to a nearby Nile island called Agilkia [related U.T. article]. This becomes a part of the Rosetta story – a lander named Philae in reference to the obelisks used along with the Rosetta stone to decipher Eqyptian writings, departing its mother ship on a short but critical voyage to a final resting place, the landing site now called Agilkia.

Upon landing, a landing confirmation signal is expected from Philae via Rosetta at about 8:02 AM PST (11:02 AM EST, 17:02 Central European Time). Alexandre Brouste of France, the designated winner of the landing site naming contest will be in Darmstadt, Germany in mission control to watch the landing unfold with the Rosetta engineers and scientists. Surely, millions of citizens of the European Union and people worldwide will be watching via the World Wide Web.

The timeline and events to unfold as Philae, the lander is released from Rosetta, the comet orbiter. (Illustration Credit: ESA)
The timeline and events to unfold as Philae, the lander is released from Rosetta, the comet orbiter. (Illustration Credit: ESA)

Previous Rosetta and Philae articles at Universe Today

Rosetta’s Philae Lander: A Swiss Army Knife of Scientific Instruments

Why Watch ESA Rosetta’s Movie ‘Ambition’? Because We Want to Know What is Possible