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Rosetta spacecraft has made a very surprising discovery – namely that the molecular breakup mechanism of “water and carbon dioxide molecules spewing from the comet’s surface” into the atmosphere of comet 67P/Churyumov-Gerasimenko is caused by “electrons close to the surface.” The surprising results relating to the emission of the comet coma came from measurements gathered by the probes NASA funded Alice instrument and is causing scientists to completely rethink what we know about the wandering bodies, according to the instruments science team. “The discovery we’re reporting is quite unexpected,” said Alan Stern, principal investigator for the Alice instrument at the...

Scientists from Rosetta’s OSIRIS team have discovered an extraordinary formation on the larger lobe of comet 67P/Churyumov-Gerasimenko in the Aker region. From a group of three boulders the largest one with a diameter of approximately 30 meters stands out: images obtained on 16 September 2014 from a distance of 29 kilometers with the help of Rosetta’s scientific imaging system OSIRIS show it to perch on the rim of a small depression. There seems to be only a very small contact area with the nucleus. Similar geological formations are found also on Earth. So-called balancing rocks touch the underground with only...

Explanation: What that looming behind this gravel-strewn hill on Comet Churyumov–Gerasimenko? A jagged cliff. The unusual double-lobed nucleus of Comet 67P/Churyumov–Gerasimenko lends itself to unusual and dramatic vistas, another of which has been captured by the Rosetta spacecraft that arrived at the comet last September. The featured cometscape, taken last October and digitally enhanced, spans about 850 meters across. Meanwhile, Comet Churyumov–Gerasimenko continues to sprout jets as it nears its closest approach to the Sun in August. Along the way, Rosetta will continue listening for signals from Philae, a probe that landed on the nucleus but rebounded to an unknown...

Explanation: What's happening to Comet 67P/Churyumov-Gerasimenko? As the 3-km wide comet moves closer to the Sun, heat causes the nucleus to expel gas and dust. The Rosetta spacecraft arrived at the comet's craggily double nucleus last July and now is co-orbiting the Sun with the giant dark iceberg. Recent analysis of data beamed back to Earth from the robotic Rosetta spacecraft has shown that water being expelled by 67P has a significant difference with water on Earth, indicating that Earth's water could not have originated from ancient collisions with comets like 67P. Additionally, neither Rosetta nor its Philae lander detected...

"The gas jets coming out of the comet - they are acting like thrusters and are slowing down the comet," said flight director Andrea Accomazzo. The European Space Agency official was speaking this week at the Royal Aeronautical Society in London. He was describing how his team has learnt to fly Rosetta around the 10-billion-tonne, 4km-wide body with remarkable precision. Navigators use a system of landmarks on the comet to understand how it is rotating and moving through space. This information is fed into a model that helps plan a trajectory for the satellite. And it was while running this...

CLICK ON THE PICTURE FOR THE VIDEO REPORT: Video Report on the Electric Universe Explanation for the findings on 67P's Mysterious Water Production

The European Space Agency says high-resolution images the Rosetta space probe took during a swoop close to a comet it's been tracking for months show boulders on the comet's surface as well as "stunning details of the contrasting terrain." The agency said Monday the boulders ranged in size from a few meters (yards) to a few tens of meters, and lie "scattered across the whole surface of the comet." It says the sun was directly behind Rosetta as the pictures were taken, providing optimal light conditions.

Explanation: Where do comet tails come from? Although it is common knowledge that comet tails and comas originate from comet nuclei, exactly how that happens is an active topic of research. One of the best images yet of emerging jets is shown in the featured image, taken last November by the robotic Rosetta spacecraft in orbit around the Comet 67P/Churyumov-Gerasimenko (Comet CG), and released last month. The overexposed picture shows plumes of gas and dust escaping numerous places from the Comet CG's nucleus as it nears the Sun and heats up. Although Comet CG is currently further out from the...

Despite its solid appearance, 67P is highly porous with a density similar to wood or cork and orbited by a cloud of approximately 100,000 “grains” of material larger than 2 inches (5 cm) across stranded there after the comet’s previous perihelion passage. ... Researchers have identified 19 distinct geological regions on the comet and five basic types of terrain: dust-covered, brittle material, large-scale depressions, smooth terrains and consolidated surfaces. ... Using a spectrometer to scan the comet’s surface researchers discovered complex organic (carbon-based) molecules that could include carboxylic acids – a component of amino acids. These organics only form in...

The crack, or fissure, could spell the beginning of the end for comet 67P/Churyumov–Gerasimenko. It is located in the neck area, in the region named Hapi, between the two lobes that make 67P appear so much like a Rubber Duck from a distance. The fissure could represent a focal point of many properties and forces at work, such as the rotation rate and axis – basically head over heels of the comet. The fissure lies in the most active area at present, and possibly the most active area overall. Though the Hapi region appears to receive nearly constant sunlight, at...

Researchers working with Rosetta have found that the comet harbors organic compounds, carbon-based molecules that are sometimes known as the chemical building blocks of life. This marks the first time organic molecules have been detected on the surface of a comet's nucleus, according to Fabrizio Capaccioni, the principal investigator of the VIRTIS instrument on Rosetta. The northern hemisphere of the comet's nucleus is also filled with dunes and ripples that look somewhat like geological markings on Earth, Mars and Venus. Comet 67P/C-G doesn't have a robust atmosphere and high gravity like those planets, and yet it still has structures resembling...

Explanation: These high cliffs occur on the surface of a comet. They were discovered to be part of the dark nucleus of Comet Churyumov–Gerasimenko (CG) by Rosetta, a robotic spacecraft launched by ESA which began orbiting the comet in early August. The ragged cliffs, as featured here, were imaged by Rosetta about two weeks ago. Although towering about one kilometer high, the low surface gravity of Comet CG would likely make a jump from the cliffs, by a human, survivable. At the foot of the cliffs is relatively smooth terrain dotted with boulders as large as 20 meters across. Data...

Images from space don’t get more dramatic than this. Image processing wizard Stuart Atkinson zoomed in on one of the most intriguing views yet of Comet 67P/Churyumov-Gerasimenko, highlighting the contrasts of dark and light, smooth and rugged, soft contours and frighteningly vertical cliffs.

The question about the origin of oceans on Earth is one of the most important questions with respect to the formation of our planet and the origin of life. The most popular theory is that water was brought by impacts of comets and asteroids. Data from the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument aboard the European Space Agency’s Rosetta spacecraft indicate that terrestrial water did not come from comets like 67P/Churyumov-Gerasimenko. The findings were published today in the journal Science. Researchers agree that water must have been delivered to Earth by small bodies at a later...

Rosetta's lander lasted just 60 hours on a comet after it bounced into the dark shadows of a cliff, where its solar panels couldn't power the vehicle. Why didn't it carry a more reliable power source, say a nuclear battery like one that's unfailingly fueled Voyager for decades? It's a simple question with a fascinating answer, one that begins with the Cold War and ends with the future space exploration. When it comes to space travel, plutonium-238 is the perfect fuel: long-lasting and, as I'll explain later, relatively safe. Without it, we have no hope of going much further than...

As the European Space Agency scurries to find the final resting place of the Philae lander, Rosetta continues normal operations above the comet and will keep tracking it through 2015. Rosetta is the first orbiter to stick around near a comet, which will allow scientists an unprecedented chance to see a comet change from up close as the Sun’s heat and particles affect it. Could there be an atmosphere starting up? “At the bottom of the mosaic, the non-illuminated part of the comet stands out as a silhouette against the broader diffuse emission coming from the comet’s coma,” ESA stated....

Explanation: Get out your red/blue glasses and float next to a comet! The Rosetta mission lander Philae's ROLIS camera snapped the two frames used to create this stereo anaglyph for 3D viewing during its November 12 descent to the nucleus of Comet 67P/Churyumov-Gerasimenko. The comet's curious double lobed nucleus is seen nearly end on from a distance of about 3 kilometers, about 1 hour before Philae arrived at the surface. Philae's initial landing site is near the center of the front facing lobe. Part of a landing gear foot cuts across the upper right corner, in the close foreground of...

Asteroid 62412. Credit: Scott Sheppard Comets are often called “dirty snowballs” by astronomers. However, various investigative missions, such as Giotto and Deep Impact, revealed them to be blackened, cratered, and fractured. No ice fields, reflective crust, or watery clouds were observed. Indeed, the latest pictures from the Rosetta mission of 67P/Churyumov-Gerasimenko indicate that it is a mountain of rock in space. According to a recent press release, the Gemini Observatory’s image of asteroid 62412, located between Mars and Jupiter, is the first time that one of the Hygiea family of asteroids has exhibited a tail, and is only the...

This Hubble Space Telescope model from 2003 shows us why. From afar, Comet 67P/Churyumov-Gerasimenko is a tiny object to image, even for the NASA probe’s powerful lens. Back then, the telescope was tasked with examining the comet to look at its size and shape to better design the Philae lander spacecraft. And the model reveals no duckie; it looks more like a sombrero from some angles. The main concern of scientists back then was redirecting Rosetta to a new target when its original comet (46P/Wirtanen) fell out of reach due to a launch delay. 67P was bigger and had a...

With just 60 hours of battery power, the lander drilled, hammered and gathered science data on the surface of comet 67P/Churyumov-Gerasimenko before going into hibernation. Despite appearances, the comet’s hard as ice. The team responsible for the MUPUS (Multi-Purpose Sensors for Surface and Sub-Surface Science) instrument hammered a probe as hard as they could into 67P’s skin but only dug in a few millimeters: “Although the power of the hammer was gradually increased, we were not able to go deep into the surface,” said Tilman Spohn ... “If we compare the data with laboratory measurements, we think that the probe...