Photo Gallery: Step Right Up And Tour Rosetta’s Comet! Where Shall We Land?

What’s one of the first things you do when arriving at a new destination? Likely it would be scoping out the local neighborhood. Getting a sense of its terrain and the good things to do around there.

That’s part of what Rosetta’s team is working on since arriving at its comet early in the morning of Aug. 6 (Eastern time). While only a few pictures have been beamed back to the public so far of Comet 67P/Churyumov-Gerasimenko, the glimpses of its surface are tantalizing. Which is important, because a little spacecraft is on its way there.

As the team busily calibrates its instruments and snaps pictures of the surface, one of their first tasks will be to pick a landing site for Philae, the machine that is scheduled to leave Rosetta and actually touch softly down on the surface in November. This is the first time such a soft-landing has been attempted, and it’s been a long decade of waiting for the scientists who sent the two spacecraft on their way.

Picking a spot will be difficult for the team, they explained last week. The gravity is light and the terrain is not only difficult to navigate, but also hard to choose from. Would you prefer a crater or a cliff? That will be what science investigators will examine in the coming months.

As they do that, check out the latest pictures of the comet in the gallery below.

A view of Comet 67P/Churyumov-Gerasimenko taken by the Rosetta spacecraft on Aug. 9, 2014. Credit: ESA/Rosetta/NAVCAM
A view of Comet 67P/Churyumov-Gerasimenko taken by the Rosetta spacecraft on Aug. 9, 2014. Credit: ESA/Rosetta/NAVCAM
A dark hollow beckons in this picture of Comet 67P/Churyumov-Gerasimenko taken by the Rosetta spacecraft Aug. 5, 2014. Credit:  ESA/Rosetta/NAVCAM
A dark hollow beckons in this picture of Comet 67P/Churyumov-Gerasimenko taken by the Rosetta spacecraft Aug. 5, 2014. Credit: ESA/Rosetta/NAVCAM
The Rosetta spacecraft captured the "rubbe duckie" shape of Comet 67P/Churyumov-Gerasimenko on Aug. 6, 2014. Credit: ESA/Rosetta/NAVCAM
The Rosetta spacecraft captured the “rubbe duckie” shape of Comet 67P/Churyumov-Gerasimenko on Aug. 6, 2014. Credit: ESA/Rosetta/NAVCAM
The mottled surface of Comet 67P/Churyumov-Gerasimenko beckons in this picure taken by the Rosetta spacecraft on Aug. 7, 2014. Credit: ESA/Rosetta/NAVCAM
The mottled surface of Comet 67P/Churyumov-Gerasimenko beckons in this picure taken by the Rosetta spacecraft on Aug. 7, 2014. Credit: ESA/Rosetta/NAVCAM

New Image of Rosetta’s Comet Reveals So Much More

WOW! We’re really getting to the good stuff now! This is no computer-generated shape model, this is the real deal: the double-lobed nucleus of Comet 67P/C-G, as imaged by Rosetta’s OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) narrow-angle camera on Tuesday, July 29. At the time just about a week away from making its arrival, ESA’s spacecraft was 1,950 km (1,211 miles) from the comet when this image was taken. (That’s about the distance between Providence, Rhode Island and Miami, Florida… that’s one fancy zoom lens, Rosetta!)

Comet 67P/Churyumov-Gerasimenko was imaged on 14 July 2014 by OSIRIS, Rosetta’s scientific imaging system, from a distance of approximately 12 000 km. This movie uses a sequence of 36 interpolated images each separated by 20 minutes, providing a 360° preview of the complex shape of the comet. (ESA)
Comet 67P/Churyumov-Gerasimenko imaged on July 14, 2014 by OSIRIS from a distance of approximately 12,000 km. (ESA)

This latest image reveals some actual surface features of the 4-km-wide comet, from a few troughs and mounds to the previously-noted bright band around the “neck” connecting the two lobes. The resolution in the July 29 OSIRIS image is 37 meters per pixel.

Since Rosetta is quickly closing the gap between itself and the comet we can only expect better images to come in the days ahead, so stay tuned — this is going to be an exciting August!

Keep up with the latest news on ESA’s Rosetta blog here, and find out where exactly Rosetta and Comet 67P/C-G are in the Solar System here.

Watch: Once Upon a Time There Was a Spacecraft Called Rosetta

Image credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Source: ESA

Rosetta Zooms Toward an Extraordinary Comet

I thought the photos earlier this week were amazing.  This little movie, made of 36 ‘smoothed’ or interpolated images of Comet 67P/Churyumov-Gerasimenko, takes it to the next level, showing the comet’s complex shape even more clearly as Rosetta nudges ever closer to its target. Some have likened it to a duck, a boot and even a baby’s foot. The original photos used for the animation were more pixelated, but a technique known as “sub-sampling by interpolation” was used to smooth out the pixels for a more natural look. Be aware that because of processing,  67P C-G appears smoother than it might be. While the surface looks textured, including what appears to be  a small crater atop the duck’s head, we have to be careful at this stage not to over-interpret – some of the details are artifacts. 

Raw pixelated image of the comet (left) and after smoothing. Credit: ESA
Raw pixelated image of the comet (left) and after smoothing. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

No one knows yet how such an unusual shape formed in the first place. Possibly the comet is a ‘contact binary’ made of two separate comets or two parts of  larger, shattered comet that stuck together during a low-velocity collision. This may have happened more 4 billion years ago when the icy building blocks of the planets and comets were numerous and collisions far more frequent than they are today. Contact binaries aren’t uncommon; we see them in asteroids and comets alike.

The Rosetta blog lists other intriguing scenarios:

* The comet may have once been a more spherical object but after many trips around the sun developed an asymmetrical shape from ice vaporization and outgassing.

* A near-catastrophic impact blasted away a huge chunk of comet ice.

* The strong gravitational pull experienced during a close pass of a large planet like Jupiter or Saturn may have pulled it into an irregular shape.

* A large outburst could have weakened a region on the comet’s surface that later crumbled away.

 

Detailed view of the likely contact binary asteroid 25143 Itokawa visited by the Japanese spacecraft Hayabusa in 2005. Credit: JAXA
Detailed view of the likely contact binary asteroid 25143 Itokawa visited by the Japanese spacecraft Hayabusa in 2005. Credit: JAXA

“We will need to perform detailed analyses and modelling of the shape of the comet to determine how best we can fly around such a uniquely shaped body, taking into account flight control and astrodynamics, the science requirements of the mission, and the landing-related elements like landing site analysis and lander-to-orbiter visibility,” said Rosetta Mission Manager Fred Jansen. ” But with fewer than 10,000 km to go before the August 6th rendezvous, our open questions will soon be answered.”

In the meantime, keep the photos and movies coming. We can’t get enough.

How Big is Rosetta’s Comet?

Pretty darn big, I’d say.

The illustration above shows the relative scale of the comet that ESA’s Rosetta and Philae spacecraft will explore “up-close and personal” later this year. And 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!

Artist's impression (not to scale) of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. Credit: ESA–C. Carreau/ATG medialab.
Artist’s impression (not to scale) of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. Credit: ESA–C. Carreau/ATG medialab.

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 2 there are a total of five more to go. See details of Rosetta’s burn maneuvers here.

As incredibly sensitive as they are, Rosetta’s instruments — which were able to detect the water vapor coming from Comet 67P/C-G from a distance of over 360,000 km — have even sniffed the hydrazine exhaust from its own thruster burns.

Luckily the remaining burns are relatively small compared to the first three, with the final being very brief, so any data contamination by Rosetta’s own exhaust shouldn’t become an issue once the spacecraft has established orbit in August.

Read more: Rosetta’s Comet Already Sweating the Small Stuff

Launched in March 2004, ESA’s Rosetta mission will be the first to orbit and land a probe on a comet, observing its composition and behavior as it makes its close approach to the Sun in 2015. Click here to see where Rosetta is right now.

Source: ESA’s Rosetta blog

Note: While 3-5 km seems pretty big (especially when stood on end) comet nuclei can be much larger, 10 to 20 km in diameter up to the enormous 40+ km size of Hale-Bopp. As comets go, 67P/C-G is fairly average. (Except that, come August, it will be the only comet with an Earthly spacecraft in tow!)

Rosetta’s Comet Already Sweating The Small Stuff, Far From The Sun

Feeling thirsty? If you could somehow capture the water vapor from Rosetta’s comet, you would have the equivalent of two water glasses every second. That’s more than scientists expected given that Comet 67P/Churyumov–Gerasimenko is still screaming into the inner solar system at more than double the distance from Mars to the Sun.

“We always knew we would see water vapor outgassing from the comet, but we were surprised at how early we detected it,” stated Sam Gulkis, the instrument’s principal investigator at NASA’s Jet Propulsion Laboratory in California.

“At this rate, the comet would fill an Olympic-size swimming pool in about 100 days. But, as it gets closer to the Sun, the gas production rate will increase significantly. With Rosetta, we have an amazing vantage point to observe these changes up close and learn more about exactly why they happen.”

Comets are sometimes called “dirty snowballs” because they are collection of debris and ices. From their origin points in the outer solar system, occasionally one will be pushed towards the Sun.

Artist's impression (not to scale) of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. Credit: ESA–C. Carreau/ATG medialab.
Artist’s impression (not to scale) of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. Credit: ESA–C. Carreau/ATG medialab.

As it gets closer, the ices bleed off and the comet develops an envelope of gases that eventually, with the Sun’s help, will turn into a tail. Some of the major “volatiles” include water, carbon monoxide, methanol and ammonia.

The observations were made on June 6 by an instrument called the Microwave Instrument for Rosetta Orbiter (MIRO), taken when the spacecraft was about 218,000 miles (350,000 km) away from its target. MIRO is trying to figure out the relative ratios of the ingredients of the coma, and will keep following along with the comet as it makes its closest approach to the sun in August 2015.

Rosetta, meanwhile, will get up close to Comet 67P/Churyumov–Gerasimenko by August and if all goes well, subsequently deploy a lander called Philae to check out the surface of the comet.

Source: European Space Agency

Rosetta Detects Water on its Target Comet

It’s no surprise that there is a lot of water in comets. The “dirty snowballs” (or dusty ice-balls, more accurately) are literally filled with the stuff, so much in fact it’s thought that comets played a major role in delivering water to Earth. But every comet is unique, and the more we learn about them the more we can understand the current state of our Solar System and piece together the history of our planet.

ESA’s Rosetta spacecraft is now entering the home stretch for its rendezvous with comet 67P/Churyumov-Gerasimenko in August. While it has already visually imaged the comet on a couple of occasions since waking from its hibernation, its instruments have now successfully identified water on 67P for the first time, from a distance of 360,000 km — about the distance between Earth and the Moon.

The detection comes via Rosetta’s Microwave Instrument for Rosetta Orbiter, or MIRO, instrument. The results were distributed this past weekend to users of the IAU’s Central Bureau of Astronomical Telegrams:

S. Gulkis, Jet Propulsion Laboratory, California Institute of Technology, on behalf of the Microwave Instrument on Rosetta Orbiter (MIRO) science team, reports that the (1_10)-(1_01) water line at 556.9 GHz was first detected in Comet 67P/Churyumov-Gerasimenko with the MIRO instrument aboard the Rosetta spacecraft on June 6.55, 2014 UT. The line area is 0.39 +/-0.06 K km/s with the line amplitude of 0.48 +/-0.06 K and the line width of 0.76 +/-0.12 km/s. At the time of the observations, the spacecraft to comet distance was ~360,000 km and the heliocentric distance of the comet was 3.93 AU. An initial estimate of the water production rate based on the measurements is that it lies between 0.5 x 10^25 molecules/s and 4 x 10^25 molecules/s.

Although recent images of 67P/C-G seem to show that the comet’s brightness has decreased over the past couple of months, it is still on its way toward the Sun and with that will come more warming and undoubtedly much more activity. These recent measurements by MIRO show that the comet’s water production rate is “within the range of models being used” by scientists to anticipate its behavior.

Rosetta image of Comet 67P/C-G on June 4, 2014, from a distance of 430,000 km. Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
Rosetta image of Comet 67P/C-G on June 4, 2014, from a distance of 430,000 km. Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Read more: What Will Rosetta’s Comet Look Like?

This August Rosetta will become the first spacecraft to establish orbit around a comet and, in November, deploy its Philae lander onto its surface. Together these robotic explorers will observe first-hand the changes in the comet as it makes its closest approach to the Sun in August 2015. It’s going to be a very exciting year ahead, so stay tuned for more!

Learn more about the Rosetta mission here.

Source: ESA’s Rosetta blog

 

What Will Rosetta’s Comet Look Like? How Artists Over The Years Pictured It

Comets are notoriously hard to predict — just ask those people on Comet ISON watch late in 2013. So as Rosetta approaches its cometary target, no one really knows what the comet will look like from up close. Yes, there are pictures of other cometary nuclei (most famously, Halley’s Comet) but this one could look completely different.

Several artists have taken a stab at imagining what Rosetta will see when it gets close to the comet in August, and what Philae will touch on when it reaches the surface in November. You can see their work throughout this article.

Meanwhile, the European Space Agency just issued an update on what they can see of 67P/Churyumov–Gerasimenko from half a million km away — the comet is quieter, they said.

“Strikingly, there is no longer any sign of the extended dust cloud that was seen developing around nucleus at the end of April and into May,” ESA stated in a press release. “Indeed, monitoring of the comet has shown a significant drop in its brightness since then.”

Artist's impression (from 2002) of Rosetta orbiting Comet 67P/Churyumov-Gerasimenko. Credit: ESA, image by AOES Medialab
Artist’s impression (from 2002) of Rosetta orbiting Comet 67P/Churyumov-Gerasimenko. Credit: ESA, image by AOES Medialab

This variability is common in comets, but it’s the first time it’s been seen from so close, ESA said. Comets warm up as they approach the sun, releasing ice, gas and dust that form a swarm of material.

“As comets are non-spherical and lumpy, this process is often unpredictable, with activity waxing and waning as they warm. The observations made over the six weeks from the end of April to early June show just how quickly the conditions at a comet can change,” ESA added.

For more about Philae’s landing, check out this past article from Universe Today.

Rosetta flies above the Philae lander on Comet 67P/Churyumov-Gerasimenko in this artist's impression from 2002. Credit: Astrium - E. Viktor
Rosetta flies above the Philae lander on Comet 67P/Churyumov-Gerasimenko in this artist’s impression from 2002. Credit: Astrium – E. Viktor
Artist's impression (from 2002) of the Philae lander during descent on Comet 67P/Churyumov-Gerasimenko. Credit: ESA, image by AOES Medialab
Artist’s impression (from 2002) of the Philae lander during descent on Comet 67P/Churyumov-Gerasimenko. Credit: ESA, image by AOES Medialab
Rosetta flies above Comet 67P/Churyumov–Gerasimenko in this 2013 artist's impression. Credit: ESA–C. Carreau/ATG medialab
Rosetta flies above Comet 67P/Churyumov–Gerasimenko in this 2013 artist’s impression. Credit: ESA–C. Carreau/ATG medialab
Artist's impression (from 2013) of the Philae lander on the surface of Comet 67P/Churyumov-Gerasimenko. Credit: ESA/ATG medialab
Artist’s impression (from 2013) of the Philae lander on the surface of Comet 67P/Churyumov-Gerasimenko. Credit: ESA/ATG medialab

ESA Awakens Rosetta’s Comet Lander

Little Philae is awake! ESA sent a wake-up call to the 100-kg (220-lb) lander riding aboard the Rosetta spacecraft this morning at 06:00 GMT, bringing it out of its nearly 33-month-long slumber and beginning its preparation for its upcoming (and historic) landing on the surface of a comet in November.

Unlike Rosetta, which awoke in January via a pre-programmed signal, Philae received a “personal wake-up call” from Earth, 655 million kilometers away.

Hello, world! ESA's Rosetta and Philae comet explorers are now both awake and well!
Hello, world! ESA’s Rosetta and Philae comet explorers are now both awake and well!

A confirmation signal from the lander was received by ESA five and a half hours later at 11:35 GMT.

After over a decade of traveling across the inner Solar System, Rosetta and Philae are now in the home stretch of their ultimate mission: to orbit and achieve a soft landing on the inbound comet 67/P Churyumov-Gerasimenko. It will be the first time either feat has ever been attempted — and hopefully achieved — by a spacecraft.

Read more: Rosetta Spacecraft Spies Its Comet As It Prepares For An August Encounter

After Rosetta maneuvers to meet up with the comet in May and actually enters orbit around it in August, it will search its surface for a good place for Philae to make its landing in November.

With a robotic investigator both on and around it, 67/P CG will reveal to us in intimate detail what a comet is made of and really happens to it as it makes its close approach to the Sun.

“Landing on the surface is the cherry on the icing on the cake for the Rosetta mission on top of all the great science that will be done by the orbiter in 2014 and 2015. A good chunk of this year will be spent identifying where we will land, but also taking vital measurements of the comet before it becomes highly active. No one has ever attempted this before and we are very excited about the challenge!”
– Matt Taylor, Rosetta project scientist

Meanwhile, today’s successful wake-up call let the Rosetta team know Philae is doing well. Further systems checks are planned for the lander throughout April.

Watch an animation of the deployment and landing of Philae on comet 67/P CG below:

Source: ESA’s Rosetta blog

Want to welcome Rosetta and Philae back on your computer? Download a series of ESA’s “Hello, World” desktop screens here.

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.

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]