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It was the greatest puzzle in the world. For three thousand years the ancient Egyptians covered the walls and ceilings of their temples and tombs with a form of writing known as hieroglyphs. More, the bone-dry climate of Egypt had preserved vast quantities of this hieroglyphic text written on papyrus. And in 1800, no one on earth could read a word of it. When Egypt became Christian in the fourth century A.D., the use of these hieroglyphs, associated with paganism, died out. The last known hieroglyphic inscription was chiseled into stone in the year 394. Within a generation, the last...

Comet 67P, which famously hosted the first-ever cometary lander in 2014, made its closest approach to Earth on Friday (Nov. 12). The comet, which is now bright enough to observe with amateur telescopes, will not come back to our planet for the next 200 years. During its closest pass at 7:50 pm EST (0050 GMT), Comet 67P was at a distance of 39 million miles (62.8 million kilometres) from our planet, within the orbit of Mars, according to Astronomy Now. Nine days earlier, the comet passed perihelion, the closest point to the sun in its elliptical orbit around our star....

The parent Rosetta spacecraft is working well in orbit and still transmitting images of the comet while Philae hibernates in a shady spot below. This latest image here shows a clear view of where the European Space Agency thinks the lander arrived — somewhere in the rim of that shadowy crater you see up front.

The Rosetta spacecraft may have crashed in 2016, but it still has secrets to share. The European Space Agency (ESA) recently released breathtaking images that the craft took in 2014 as it orbited just 16 miles above the surface of Comet 67P. The image was put together by amateur astronomer Jacint Roger Perez using three separate photos taken by Rosetta during the flyby. Comet 67P is approximately 2.7 by 2.5 miles at its longest and widest dimensions, and is made up of 26 unique regions, each named after an Egyptian deity. The photo captures four regions of the comet....

Ever since we’ve been able to get closer looks at comets in our Solar System, we’ve noticed something a little puzzling. Rather than being round, they’re mostly elongated or multi-lobed. This is certainly true of Comet 67P/Churyumov-Gerasimenko (67P or Chury for short.) A new paper from an international team coordinated by Patrick Michel at France’s CNRS explains how they form this way. The European Space Agency (ESA) spacecraft Rosetta visited 67P in 2014, end even placed its lander Philae on the surface. Rosetta spent 17 months orbiting 67P, and at its closest approach, Rosetta was only 10 km (6 mi)...

After a journey of billions of miles and a historic cosmic rendezvous, the Rosetta spacecraft met its end after a “controlled impact” with the comet it had been studying. The European Space Agency (ESA) confirmed a loss of signal from the probe on Friday at 1:19 pm, Central European Summer Time. The maneuver to slowly crash the craft was deliberate— a way to study the comet up close at the tail end of the mission. “Thanks to a huge international, decades-long endeavour, we have achieved our mission to take a world-class science laboratory to a comet to study its evolution...

Rosetta fell silent moments after 6:19 a.m. Eastern Time (12:19 UT) this morning, when it gently crashed into 67P/C-G 446 million miles (718 million km) from Earth. As the probe descended to the comet’s bouldery surface of the comet in free fall, it snapped a series of ever-more-detailed photographs while gathering the last bits data on the density and composition of cometary gases, surface temperature and gravity field before the final curtain was drawn.

As it reaches the end of its life Philae, the first robot to land on a comet, has reached the end of its life and is bidding a final farewell to Earth through a series of sad tweets. “It’s time for me to say goodbye,” Philae tweeted on Tuesday. “Tomorrow, the unit on @ESA_Rosetta for communication with me will be switched off forever…” After launching from a Rosetta probe, Philae landed on 67P/Churyumov-Gerasimenko in November 2014, becoming the first spacecraft to touch down on a comet. However, landing trouble led Philae to bounce across the landscape of the comet, finally...

Explanation: Spacecraft Rosetta continues to circle and map Comet Churyumov-Gerasimenko. Crossing the inner Solar System for ten years to reach the vicinity of the comet in 2014, the robotic spacecraft continues to image the unusual double-lobed comet nucleus. The featured image, taken one year ago, shows dust and gas escaping from the comet's nucleus. Although appearing bright here, the comet's surface reflects only about four percent of impinging visible light, making it as dark as coal. Comet 67P/Churyumov–Gerasimenko spans about four kilometers in length and has a surface gravity so low that an astronaut could jump off of it. With...

The finding, published Wednesday in Nature, solves a long-standing mystery about water ice in comets. Scientists already knew that the coma... is dominated by water molecules.... "It is exciting because now we are starting to understand the upper dynamic layers of the comet and how they evolved." The surface of comet 67P, like most comets, is primarily covered by dark organic materials that appear almost black. That's because as comets fly toward the sun, they are exposed to warm temperatures that cause volatiles like water ice on their surface to sublimate - or go directly from solid to gas. What...

Researchers last got a signal from the Philae lander back in July, since then pinging it has resulted in no word from it—and i'’s all coming to a head now, says the ESA, because time is running out as the comet moves further and further away from the sun. With just a little time left, the plan is to try some off-label uses of Philae's momentum wheel. If the problem is that the lander is simply too dusty to power on, the hope is that spinning the wheel could clear off enough to let it wake itself up one last...

Explanation: Not a bright comet, 67P/Churyumov-Gerasimenko now sweeps slowly through planet Earth's predawn skies near the line-up of planets along the ecliptic. Still, this composite of telescopic images follows the comet's progress as it moves away from the Sun beyond the orbit of Mars, from late September (left) through late November (far right). Its faint but extensive coma and tails are viewed against the colorful background of stars near the eastern edge of the constellation Leo. A year ago, before its perihelion passage, the comet was less active, though. Then the Rosetta mission's lander Philae made it's historic landing, touching...

Explanation: There she blows! A dramatic demonstration of how short-lived some comet jets can be was documented in late July by the robotic Rosetta spacecraft orbiting the nucleus of Comet 67P/Churyumov-Gerasimenko. The featured animation depicts changes in the rotating comet with three illuminating stills. Although the first frame shows nothing unusual, the second frame shows a sudden strong jet shooting off the 67P's surface only 20 minutes later, while the third frame -- taken 20 minutes after that -- shows but a slight remnant of the once-active jet. As comets near the Sun, they can produce long and beautiful tails...

This single frame Rosetta navigation camera image of Comet 67P/Churyumov-Gerasimenko was taken on 7 July 2015 from a distance of 154 km from the comet centre. The image has a resolution of 13.1 m/pixel and measures 13.4 km across. Credit: ESA/Rosetta/NAVCAM --------------------------------------------------------------------------------------------------------------------------------------------- Stunned scientists announced Wednesday the unexpected discovery of large quantities of oxygen on a comet which streaked past the Sun in August with a European spacecraft in tow. The find came as a "big surprise", and challenges mainstream theories on the formation of our Solar System, said scientist Andre Bieler of the University of Michigan. Measurements suggested that...

How would you like to see one of the most famous comets with your own eyes? Comet 67P/Churyumov-Gerasimenko plies the morning sky, a little blot of fuzzy light toting an amazing visitor along for the ride — the Rosetta spacecraft. When you look at the coma and realize a human-made machine is buzzing around inside, it seems unbelievable. If you have a 10-inch or larger telescope, or you’re an experienced amateur with an 8-inch and pristine skies, 67P is within your grasp. The comet glows right around magnitude +12, about as bright as it will get this apparition. Periodic comets...

Explanation: This dramatic outburst from the nucleus of Comet 67P/Churyumov-Gerasimenko occured on August 12, just hours before perihelion, its closest approach to the Sun. Completing an orbit of the Sun once every 6.45 years, perihelion distance for this periodic comet is about 1.3 astronomical units (AU), still outside the orbit of planet Earth (at 1 AU). The stark image of the 4 kilometer wide, double-lobed nucleus in bright sunlight and dark shadows was taken by the Rosetta spacecraft's science camera about 325 kilometers away. Too close to see the comet's growing tail, Rosetta maintains its ringside seat to watch the...

Popular Science (8/11, Fecht) reports that on July 29, the Rosetta spacecraft was able to capture what the ESA called a “dramatic outburst” from Comet 67P, which was strong enough to affect the solar wind. The article notes that the ESA said that “unpredictable outbursts” like this one are occurring more frequently as the comet reaches perihelion, or its closest point to the sun in its orbit, on August 13.

In a sequence of images taken by Rosetta’s scientific camera OSIRIS, the brilliant, well-defined jet erupts from the side of the comet’s neck in the Anuket region. It was first seen in a photo taken at 8:24 a.m. CDT, but not in one taken 18 minutes earlier, and had faded significantly in an image captured 18 minutes later. The camera team estimates the material in the jet was traveling at a minimum of 22 mph (10 meters/sec), but possibly much faster. It’s the brightest jet ever seen by Rosetta. Normally, the camera has to be set to overexpose 67P/C-G’s nucleus...

After first touching down, Philae was able to use its gas-sniffing Ptolemy and COSAC instruments to determine the makeup of the comet’s atmosphere and surface materials. COSAC analyzed samples that entered tubes at the bottom of the lander and found ice-poor dust grains that were rich in organic compounds containing carbon and nitrogen. It found 16 in all including methyl isocyanate, acetone, propionaldehyde and acetamide that had never been seen in comets before. Ptolemy sampled the atmosphere entering tubes at the top of the lander and identified water vapor, carbon monoxide and carbon dioxide, along with smaller amounts of carbon-bearing...

Experts discover dark material is being constantly replenished and say: "Something must be doing that at a fairly prolific rate."Evidence of alien life is "unequivocal" on the comet carrying the Philae probe through space, two leading astronomers have said. The experts say the most likely explanation for certain features of the 67P/Churyumov-Gerasimenko comet, such as its organic-rich black crust, is the presence of living organisms beneath an icy surface. Rosetta, the European spacecraft orbiting the comet, is also said to have picked up strange "clusters" of organic material that resemble viral particles. But neither Rosetta nor its lander probe, Philae,...