Check Out This Huge Rock On The Surface Of Rosetta’s Comet!

As the Rosetta spacecraft drops a bit closer to its target comet, some really cool features are popping into view. For example, look at this picture of a 150-foot (45-meter) rock on Comet 67P/Churyumov-Gerasimenko, which was taken in September and released today (Oct. 9). And it’s led to the decision to have an Egyptian theme to naming features on the comet.

“It stands out among a group of boulders in the smooth region located on the lower side of 67P/C-G’s larger lobe,” ESA stated in a release. “This cluster of boulders reminded scientists of the famous pyramids at Giza near Cairo in Egypt, and thus it has been named Cheops for the largest of those pyramids, the Great Pyramid, which was built as a tomb for the pharaoh Cheops (also known as Kheops or Khufu) around 2550 BC.”

Scientists are still trying to figure out what the boulders are made of, and how they are formed, as the spacecraft moves into a “close observation phase” tomorrow (Oct. 10) where it is only 10 kilometers (6.2 miles) from the surface.

A wider field of view of 67P/Churyumov-Gerasimenko on the larger lobe, where the boulder Cheops is located. This picture was taken by the Rosetta spacecraft shortly after its arrival in August. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
A wider field of view of 67P/Churyumov-Gerasimenko on the larger lobe, where the boulder Cheops is located. This picture was taken by the Rosetta spacecraft shortly after its arrival in August. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Meanwhile, some new results are coming from an asteroid that the spacecraft whizzed by a couple of years ago. In the picture below, you can see evidence of a crater that Rosetta didn’t even see!

The grooves you see there on Lutetia (which Rosetta imaged in 2010) hint at shock waves from various craters, including one that was likely on the hidden side of the asteroid relative to Rosetta as it flew by. The suspected crater is called “Suspicio.” While craters have been found in other asteroids visited by spacecraft, grooves are rarer.

“The way in which grooves are formed on these bodies is still widely debated, but it likely involves impacts,” ESA stated. “Shock waves from the impact travel through the interior of a small, porous body and fracture the surface to form the grooves.”

A paper on the research will be published in Planetary and Space Science this month, led by Sebastien Besse, a research fellow at ESA’s Technical Centre. For more information, check out this release from ESA.

A part of asteroid Lutetia imaged by the Rosetta spacecraft in 2010. The grooves you see are colored according to the crater scientists believe it’s associated with. The blue lines are from a suspected, unseen crater called “Suspicio”. Red is associated with the known crater Massilia and purple for the North Pole Crater Cluster. Yellow is unassociated with craters considered in this study. Credit: Data: Besse et al (2014); image: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Asteroid Lutetia Flyby Animation

In today’s Weekly Space Hangout, Emily Lakdawalla from the Planetary Society mentioned an animation of recently released images from the Rosetta mission’s flyby of asteroid Lutetia. It was put together and processed by Ian Regan, and Emily suggested you play this on a hand-held device (like a smart phone) in a dark room and move it around like you yourself are maneuvering the flyby! Try it — it is a very cool effect!

And while you’re at it, you also need to check out Emily’s montage poster of asteroids and comets, below:


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Check out more pretty images of Lutetia by Emily at the Planetary Blog.

Asteroid Lutetia… A Piece Of Earth?

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According to data received from ESA’s Rosetta spacecraft, ESO’s New Technology Telescope, and NASA telescopes, strange asteroid Lutetia could be a real piece of the rock… the original material that formed the Earth, Venus and Mercury! By examining precious meteors which may have formed at the time of the inner Solar System, scientists have found matching properties which indicate a relationship. Independent Lutetia must have just moved its way out to join in the main asteroid belt…

A team of astronomers from French and North American universities have been hard at work studying asteroid Lutetia spectroscopically. Data sets from the OSIRIS camera on ESA’s Rosetta spacecraft, ESO’s New Technology Telescope (NTT) at the La Silla Observatory in Chile, and NASA’s Infrared Telescope Facility in Hawaii and Spitzer Space Telescope have been combined to give us a multi-wavelength look at this very different space rock. What they found was a very specific type of meteorite called an enstatite chondrite displayed similar content which matched Lutetia… and what is theorized as the material which dates back to the early Solar System. Chances are very good that enstatite chondrites are the same “stuff” which formed the rocky planets – Earth, Mars and Venus.

“But how did Lutetia escape from the inner Solar System and reach the main asteroid belt?” asks Pierre Vernazza (ESO), the lead author of the paper.

It’s a very good question considering that an estimated less than 2% of the material which formed in the same region of Earth migrated to the main asteroid belt. Within a few million years of formation, this type of “debris” had either been incorporated into the gelling planets or else larger pieces had escaped to a safer, more distant orbit from the Sun. At about 100 kilometers across, Lutetia may have been gravitationally influenced by a close pass to the rocky planets and then further affected by a young Jupiter.

“We think that such an ejection must have happened to Lutetia. It ended up as an interloper in the main asteroid belt and it has been preserved there for four billion years,” continues Pierre Vernazza.

Asteroid Lutetia is a “real looker” and has long been a source of speculation due to its unusual color and surface properties. Only 1% of the asteroids located in the main belt share its rare characteristics.

“Lutetia seems to be the largest, and one of the very few, remnants of such material in the main asteroid belt. For this reason, asteroids like Lutetia represent ideal targets for future sample return missions. We could then study in detail the origin of the rocky planets, including our Earth,” concludes Pierre Vernazza.

Original Story Source: ESO News Release.

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.