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Keyword: comets

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  • Centaurs Keep Their Rings From Greedy Gas Giants

    06/26/2016 10:36:02 AM PDT · by BenLurkin · 14 replies ^ | 06/24/2016 | Matt Williams
    Centaurs are a population of objects within our Solar System that behave as both comets and asteroids (hence why they are named after the hybrid beasts of Greek mythology). 10199 Chariklo is the largest known member of the Centaur population, a possible former Trans-Neptunian Object (TNO) which currently orbits between Saturn and Uranus. The rings around this asteroid were first noticed in 2013 when the asteroid underwent a stellar occultation. This revealed a system of two rings, with a radius of 391 and 405 km and widths of about 7 km 3 km, respectively. The absorption features of the rings...
  • 'Alien Megastructure' Star Only Gets More Mysterious

    05/22/2016 6:39:00 PM PDT · by 2ndDivisionVet · 53 replies
    Popular Science ^ | May 10, 2016 | Sarah Fecht
    Every now and then, a distant star called KIC 8462852 dims by as much as 20 percent. That's huge. Even a passing planet as big as Jupiter would only block about 1 percent of the star's light. Ruling out a planet, scientists have no idea what could be eclipsing the star (which is informally known as 'Tabby's Star'). The leading hypothesis is a family of really big comets, but that doesn't quite fit. Astronomer Jason Wright pointed out that the light patterns are consistent with what we'd expect if aliens had built a Dyson swarm of solar collectors around the...
  • New study supports natural causes, not alien activity, explain mystery star's behavior

    05/09/2016 8:56:03 PM PDT · by rdl6989 · 16 replies ^ | May 9, 2016 | David Salisbury
    Sorry, E.T. lovers, but the results of a new study make it far less likely that KIC 8462852, popularly known as Tabby's star, is the home of industrious aliens who are gradually enclosing it in a vast shell called a Dyson sphere. Public interest in the star, which sits about 1,480 light-years away in the constellation Cygnus, began last fall when Yale astronomer Tabetha ("Tabby") Boyajian and colleagues posted a paper on an astronomy preprint server reporting that "planet hunters" - a citizen science group formed to search data from the Kepler space telescope for evidence of exoplanets - had...
  • Dimming star remains mystery, but it's likely not caused by comets

    01/16/2016 5:52:31 PM PST · by BenLurkin · 15 replies
    cnn ^ | jareen imam
    Theories surrounding the star system KIC 8462852, also known as Tabby's Star, ranged from comets to an "alien megastructure" after the online astronomy crowdsourcing site Planet Hunter discovered an unusual light fluctuation in the star system a few years ago. A new analysis of KIC 8462852 shows that the star system, which lies about 1,500 light years away, has been gradually dimming for more than a century, and it's likely not caused by a cloud of orbiting comets. Bradley Schaefer, a physics and astronomy professor at Louisiana State University, examined data from a Harvard University archive of digitally scanned photographic...
  • 'Alien Megastructure' Mystery May Soon Be Solved

    10/28/2015 12:56:27 PM PDT · by ETL · 59 replies ^ | October 28, 2015 | Mike Wall - Senior Writer
    The mystery behind a strangely dimming star could soon be solved. Astronomers around the world are keeping a close eye on the star KIC 8462852, which has dimmed dramatically numerous times over the past few years, dropping in brightness by up to 22 percent. These big dips have spurred speculation that the star may be surrounded by some type of alien megastructure — a hypothesis that will be put to the test if and when KIC 8462852 dims again. "As long as one of those events occurs again, we should be able to catch it in the act, and then...
  • SETI Institute undertakes search for alien signal from Kepler Star KIC 8462852

    10/24/2015 5:31:16 AM PDT · by Momaw Nadon · 16 replies
    PHYS.ORG ^ | October 22, 2015 | Bob King
    "We either caught something shortly after an event like two planets crashing together or alien intelligence," said Dr. Gerald Harp, senior scientist at the SETI Institute in Mountain View, California, referring to the baffling light variations seen in the Kepler star KIC 8462852. And he and a team from the Institute are working hard at this moment to determine which of the two it is. Beginning last Friday (Oct. 16), the Institute's Allen Telescope Array (ATA) was taken off its normal survey schedule and instead focused on KIC 8462852, one of the 150,000-plus stars studied by NASA's Kepler Mission to...
  • Did Astronomers Find Evidence of an Alien Civilization? Probably Not. But Still Cool.

    10/15/2015 8:55:50 PM PDT · by Brad from Tennessee · 32 replies
    Slate ^ | October 14, 2015 | By Phil Plait
    The paper doesn’t mention aliens, and it doesn’t even imply aliens. Not directly, at least. But the astronomers found a star so odd, with behavior so difficult to explain, that it’s clear something weird is happening there. And some of the astronomers who did the work are now looking into the idea that what they’ve found might (might!) be due to aliens. But don’t let this idea run away with you. The scientists involved are being very skeptical and approaching this the right way. The star is called KIC 8462852, and it’s one of more than a hundred thousand stars...
  • The strange star that has serious scientists talking about an alien megastructure

    10/15/2015 12:04:31 PM PDT · by grundle · 66 replies
    Washington Post ^ | October 15, 2015 | Sarah Kaplan
    “It was kind of unbelievable that it was real data,” said Yale University astronomer Tabetha Boyajian. “We were scratching our heads. For any idea that came up there was always something that would argue against it.” She was talking to the New Scientist about KIC 8462852, a distant star with a very unusual flickering habit. Something was making the star dim drastically every few years, and she wasn’t sure what. Boyajian wrote up a paper on possible explanations for the star’s bizarre behavior, and it was published recently in the Monthly Notices of the Royal Astronomical Society. But she also...
  • See Historic Comet BA14 Up Close In These New Radar Images

    03/25/2016 4:03:23 PM PDT · by BenLurkin · 12 replies
    universetoday ^ | 03/25/2016 | Bob King
    On March 22, Comet P/2016 BA14 (Pan-STARRS) flew just 2.2 million miles (3.5 million kilometers) from Earth, making it the third closest comet ever recorded. The last time a comet appeared on our doorstep was in 1770, when Lexell’s Comet breezed by at about half that distance. Through a telescope, comet BA14 looked (and still looks) like a faint star, though time exposures reveal a short, weak tail. With an excellent map and large amateur telescope you might still find it making a bead across the Big Dipper and constellation Bootes tonight through the weekend.
  • Astronomy Picture of the Day -- Close Comet and the Milky Way

    03/25/2016 2:04:22 PM PDT · by SunkenCiv · 2 replies
    NASA ^ | Friday, March 25, 2016 | (see photo credit)
    Explanation: Comet 252P/Linear's lovely greenish coma is easy to spot in this expansive southern skyscape. Visible to the naked eye from the dark site near Flinders, Victoria, Australia, the comet appears tailless. Still, its surprisingly bright coma spans about 1 degree, posed here below the nebulae, stars, and dark rifts of the Milky Way. The five panels used in the wide-field mosaic were captured after moonset and before morning twilight on March 21. That was less than 24 hours from the comet's closest approach, a mere 5.3 million kilometers from our fair planet. Sweeping quickly across the sky because it...
  • Two comets to cut it close to Earth’s orbit next week

    03/18/2016 9:33:28 PM PDT · by BenLurkin · 35 replies
    boston herald ^ | 03/18/2016
    Two comets will zoom by Earth next week within a couple million miles — a close shave, astronomically speaking — and many astronomers hope the double fly-by will tell them whether the celestial bodies were once one. At 8:14 a.m. Monday, comet 252P/LINEAR will pass within 3.3 million miles of Earth, making it the fifth-closest comet to skim by our planet. Then at 10:30 a.m. Tuesday, comet P/2016 BA14 will pass within 2.1 million miles — the third-closest comet since 1770, according to NASA officials. ... “It could be by some amazing coincidence that we are wrong, but my best...
  • Astronomy Picture of the Day -- Comet 67P from Spacecraft Rosetta

    02/02/2016 1:43:22 PM PST · by SunkenCiv · 20 replies
    NASA ^ | February 02, 2016 | (see photo credit)
    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...
  • 'Cloud' over Mars leaves scientists baffled

    02/16/2015 5:29:57 PM PST · by SunkenCiv · 63 replies
    Phys dot Org ^ | February 16, 2015 | unattributed
    Plumes seen reaching high above the surface of Mars are causing a stir among scientists studying the atmosphere on the Red Planet. On two separate occasions in March and April 2012, amateur astronomers reported definite plume-like features developing on the planet. The plumes were seen rising to altitudes of over 250 km above the same region of Mars on both occasions. By comparison, similar features seen in the past have not exceeded 100 km. "At about 250 km, the division between the atmosphere and outer space is very thin, so the reported plumes are extremely unexpected," says Agustin Sanchez-Lavega of...
  • Water On Earth Is Older Than The Sun

    09/27/2014 4:51:07 PM PDT · by SeekAndFind · 51 replies
    Science 2.0 ^ | 09/27/2014
    It's no surprise that water was crucial to the formation of life on Earth. What may surprise you is that water on earth is older than the sun itself. Identifying the original source of Earth's water is key to understanding how life-fostering environments came into being and how likely they are to be found elsewhere. A new paper in Science says that much of our Solar System's water likely originated as ices that formed in interstellar space. Water is found throughout the Solar System, not just on Earth; on icy comets and moons, and in the shadowed basins of...
  • Water Hidden in the Moon May Have Proto-Earth Origin

    09/15/2013 4:30:04 PM PDT · by SunkenCiv · 21 replies
    Science News ^ | Sep. 10, 2013 | Europlanet Media Centre
    Water found in ancient Moon rocks might have actually originated from the proto-Earth and even survived the Moon-forming event. Latest research into the amount of water within lunar rocks returned during the Apollo missions is being presented by Jessica Barnes at the European Planetary Science Congress in London on Monday 9th September. The Moon, including its interior, is believed to be much wetter than was envisaged during the Apollo era. The study by Barnes and colleagues at The Open University, UK, investigated the amount of water present in the mineral apatite, a calcium phosphate mineral found in samples of the...
  • Man Captures Video Of Strange Explosion In The Sky

    01/03/2013 2:55:34 PM PST · by BenLurkin · 31 replies
    CBS13) ^ | December 30, 2012 11:59 PM
    SACRAMENTO (CBS13) – A Sacramento man scanning the night sky caught a sudden burst of light through his telescope. He recorded that strange sight with his smart phone. CBS13 shared the video with experts to see if they could solve the mystery. This mysterious little tale begins earlier this week when Good Day Sacramento’s Cody Stark got this message on Facebook: “I have something on video no one has ever seen. I had my telescope out, caught an explosion in space. Wanna see the video?” Cody’s response? Absolutely! The video was shot with an iPhone through the eyepiece of a...
  • Solar System Ice: Source of Earth's Water

    07/14/2012 6:12:51 AM PDT · by SunkenCiv · 19 replies
    Carnegie Institution ^ | Thursday, July 12, 2012 | unattributed
    Scientists have long believed that comets and, or a type of very primitive meteorite called carbonaceous chondrites were the sources of early Earth's volatile elements -- which include hydrogen, nitrogen, and carbon -- and possibly organic material, too. Understanding where these volatiles came from is crucial for determining the origins of both water and life on the planet. New research led by Carnegie's Conel Alexander focuses on frozen water that was distributed throughout much of the early Solar System, but probably not in the materials that aggregated to initially form Earth... It has been suggested that both comets and carbonaceous...
  • Amazingly, the earths water is really a miniscule amount

    05/15/2012 10:58:01 AM PDT · by central_va · 43 replies ^ | 5/15/12 | mother earth
    The blue ball represents all of the earths water. Not that much...
  • Astronomy Picture of the Day -- All the Water on Planet Earth

    05/15/2012 4:39:34 AM PDT · by SunkenCiv · 36 replies
    NASA ^ | May 15, 2012 | (see photo credit)
    Explanation: How much of planet Earth is made of water? Very little, actually. Although oceans of water cover about 70 percent of Earth's surface, these oceans are shallow compared to the Earth's radius. The above illustration shows what would happen is all of the water on or near the surface of the Earth were bunched up into a ball. The radius of this ball would be only about 700 kilometers, less than half the radius of the Earth's Moon, but slightly larger than Saturn's moon Rhea which, like many moons in our outer Solar System, is mostly water ice. How...
  • Telescope shoots video of heavenly halo ("mystery flash" filmed from Mauna Kea, Hawaii)

    07/01/2011 1:24:50 PM PDT · by Islander7 · 41 replies
    Star Advertiser ^ | July 2, 2011 | By Jim Borg
    The pre-dawn phenomenon, which looks like a huge bubble expanding and then popping, was recorded June 22 by the Canada-France-Hawaii Telescope and the Subaru Telescope. Since then, speculation has run rampant about the source of the early morning flash. Ichi Tanaka, a support astronomer at Subaru Telescope, describes it as "a huge halo of light above the eastern horizon," adding, "It was slowly expanding to over 45 degrees in five minutes or more."
  • Military Covering Up Fireballs From Space

    06/14/2009 2:45:28 AM PDT · by JoeProBono · 23 replies · 1,289+ views
    foxnews ^ | June 11, 2009 | Leonard David
    For 15 years, scientists have benefited from data gleaned by U.S. classified satellites of natural fireball events in Earth's atmosphere — but no longer. A recent U.S. military policy decision now explicitly states that observations by hush-hush government spacecraft of incoming bolides and fireballs are classified secret and are not to be released, has learned. The satellites' main objectives include detecting nuclear bomb tests, and their characterizations of asteroids and lesser meteoroids as they crash through the atmosphere has been a byproduct data bonanza for scientists. The upshot: Space rocks that explode in the atmosphere are now classified.
  • Military Covering Up Fireballs From Space....

    06/11/2009 7:42:50 PM PDT · by TaraP · 27 replies · 1,520+ views
    Fox News ^ | June 12th, 2009
    For 15 years, scientists have benefited from data gleaned by U.S. classified satellites of natural fireball events in Earth's atmosphere — but no longer. A recent U.S. military policy decision now explicitly states that observations by hush-hush government spacecraft of incoming bolides and fireballs are classified secret and are not to be released, has learned. The satellites' main objectives include detecting nuclear bomb tests, and their characterizations of asteroids and lesser meteoroids as they crash through the atmosphere has been a byproduct data bonanza for scientists. The upshot: Space rocks that explode in the atmosphere are now classified
  • Unseen dark comets 'could pose deadly threat to earth'

    02/12/2009 3:29:16 PM PST · by SunkenCiv · 31 replies · 403+ views
    Telegraph ^ | Thursday, February 12, 2009 | Kate Devlin
    The comets, of which there could be thousands, are not currently monitored by observatories and space agencies. Most comets and asteroids are monitored in case they start to travel towards earth. But Bill Napier, from Cardiff University, said that many could be going by unnoticed. "There is a case to be made that dark, dormant comets are a significant but largely unseen hazard," he said Scientists estimate that there should be around 3,000 comets in the solar system, but only 25 have so far been identified. "Dark" comets happen when the water on their surface has evaporated, causing them to...
  • The Comet and the Future of Science

    03/10/2006 12:31:00 AM PST · by Swordmaker · 12 replies · 367+ views ^ | Feb 27, 2006
    Though NASA officials have said nothing on the subject, astronomy today is on the edge of a critical shift in perception—a revolution that could redefine our view of the heavens. Credit NASA Above, the “Great Comet” of 1996, Hyakutake. The stunning discovery of X-ray emissions from the visitor was a milestone in comet science, as was the discovery that the comet's coherent and filamentary ion tail spanned more than 350 million miles. Proponents of the “Electric Universe” say that a revolution in the sciences is inescapable, and they believe the failure of modern comet theory could be the tipping point....
  • Cosmic Hole-in-One Captured Over Antarctica

    09/05/2005 9:36:19 PM PDT · by SunkenCiv · 9 replies · 727+ views
    RedNova ^ | Monday, 5 September 2005, 20:43 CDT | staff / press release
    What a powerful telescope had picked up as it stretched towards the night sky over Antarctica was the trail of dust left in the wake of the death of an asteroid... "What he didn't know at the time was that seven hours earlier an asteroid had crashed to Earth in another part of Antarctica, about 1500 kms west of Davis. The closest it got to human habitation was around 900 kms west of Japan's Syowa station," Dr Klekociuk said... Dr Klekociuk said that it was thought that the asteroid had come from what is known as the Aten group somewhere...
  • Satellite Photo: What is this?

    05/17/2005 10:16:11 AM PDT · by demlosers · 41 replies · 1,137+ views
    Google Maps FL 33409 ^ | 17 May 2005 | Digital Globe, EarthSat
    Click here to see:,-80.074550&spn=0.005622,0.007875&t=k&hl=en
  • An Argument for the Cometary Origin of the Biosphere

    09/06/2004 8:16:38 AM PDT · by SunkenCiv · 71 replies · 1,110+ views
    American Scientist ^ | September-October 2001 | Armand H. Delsemme
    Abstract: The young Earth appear to have been bombarded by comets for several hundred million years shortly after it was formed. This onslaught, perhaps involving hundreds of millions of comet impacts, is currently the best explantion for the origin of the Earth’s oceans, atmosphere and organic molecules. Although historically a controversial idea, there is now a considerable amount of physical and chemical evidence supporting the theory. Comet scientist Armand Delsemme reviews the evidence and argues that comets from the vicinity of Jupiter contributed the bulk of the constituents found in Earth’s biosphere.
  • Researchers are Launching a Final, Desperate Effort to Contact Rosetta’s Dead Comet Lander

    01/10/2016 4:25:34 PM PST · by BenLurkin · 7 replies ^ | 01/08/2016 | Ria Misra
    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...
  • Earth-Smashing Space Rocks Undercounted

    12/23/2015 10:12:19 PM PST · by BenLurkin · 16 replies ^ | 12/22/2015 | Mariette Le Roux, AFP
    Most studies of potential Earth-smashers focus on objects in the asteroid belt roughly between Mars, Earth's outside neighbour, and Jupiter on its other flank, said the researchers. But they noted that the discovery in the last two decades of hundreds of giant comets dubbed centaurs, albeit with much larger orbits, requires expanding the list of potential hazards. These balls of ice and dust, typically 50-100 kilometres (31-62 miles) wide, have unstable, elliptical orbits that start way beyond Neptune, the most distant planet from the Sun. Their paths cross those of the giant planets Jupiter, Saturn, Uranus and Neptune, whose gravity...
  • Astronomy Picture of the Day -- Comet Catalina Emerges

    12/06/2015 9:10:59 PM PST · by SunkenCiv · 19 replies
    NASA ^ | December 07, 2015 | (see photo credit)
    Explanation: Comet Catalina is ready for its close-up. The giant snowball from the outer Solar System, known formally as C/2013 US10 (Catalina), rounded the Sun last month and is now headed for its closest approach to Earth in January. With the glow of the Moon now also out of the way, morning observers in Earth's northern hemisphere are getting their best ever view of the new comet. And Comet Catalina is not disappointing. Although not as bright as early predictions, the comet is sporting both dust (lower left) and ion (upper right) tails, making it an impressive object for binoculars...
  • Astronomy Picture of the Day -- Rosetta and Comet Outbound

    11/28/2015 8:21:10 PM PST · by SunkenCiv · 1 replies
    NASA ^ | November 28, 2015 | (see photo credit)
    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...
  • Astronomy Picture of the Day -- A Sudden Jet on Comet 67P

    11/18/2015 1:29:55 PM PST · by SunkenCiv · 2 replies
    NASA ^ | November 18, 2015 | (see photo credit)
    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...
  • The Justinian Plague of 562 A.D. an Electromagnetic Drama?

    11/02/2015 1:49:32 PM PST · by Fred Nerks · 61 replies
    Thunderbolts website ^ | October 26, 2015 | Peter Mungo Jupp
    1500 years ago a pungent world plague nearly exterminated the human race! Thomas Short wrote: “from 562 A.D. a plague raged for 52 years the like of which has never been seen before or since!” Conventional wisdom maintains this worldwide plague began in Ethiopia and was carried by ship-born rats to Europe and beyond. With our new knowledge of bacteria and viruses being carried by vectors far above the Earth this theory of deployment has been questioned. Our pertinent scrutiny asks not only what caused this exterminating plague, with its incredible and unmatched virulence, but whether some parallel catastrophic events...
  • Boozy comet leaves '500 bottles of wine per second' trail in its wake

    10/26/2015 7:26:54 PM PDT · by Fred Nerks · 40 replies
    ninemsn ^ | 27/10/2015 | N/A
    A comet with the nickname Happy Hour leaves a boozy trail equivalent to "500 bottles of wine per second" in its wake as it shoots through space. Scientists studying the comet, known as Lovejoy, have found its glowing trail is made up of alcohol and sugar. A study published by a group of scientists from NASA and European agencies observed the unusual comet as it rocketed alongside the sun on January 30, NASA reports. "You have alcohol and sugar, so that can lead to a 'happy hour' name, but I would not recommend anyone drink this water," team researcher Darek...
  • How to Find Rosetta’s Comet In Your Telescope

    08/20/2015 5:21:07 PM PDT · by BenLurkin · 9 replies
    Universe Today ^ | Bob King
    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...
  • Astronomy Picture of the Day -- Announcing Comet Catalina

    08/18/2015 1:24:48 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 18, 2015 | (see photo credit)
    Explanation: Will Comet Catalina become visible to the unaided eye? Given the unpredictability of comets, no one can say for sure, but it seems like a good bet. The comet was discovered in 2013 by observations of the Catalina Sky Survey. Since then, Comet C/2013 US10 (Catalina) has steadily brightened and is currently brighter than 8th magnitude, making it visible with binoculars and long-duration camera images. As the comet further approaches the inner Solar System it will surely continue to intensify, possibly becoming a naked eye object sometime in October and peaking sometime in late November. The comet will reside...
  • Astronomy Picture of the Day -- Perihelion Approaches

    08/15/2015 12:07:35 PM PDT · by SunkenCiv · 6 replies
    NASA ^ | August 15, 2015 | (see photo credit)
    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...
  • Rosetta's Comet Lets Out An Epic Fart [Toot, toot]

    08/12/2015 8:48:40 AM PDT · by Purdue77 · 29 replies
    Popular Science ^ | 8/11/2015 | Sarah Fecht
    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.
  • What is the Oort Cloud?

    08/10/2015 4:36:14 PM PDT · by BenLurkin · 25 replies
    Universe Today ^ | Matt Williams
    The Oort Cloud is a theoretical spherical cloud of predominantly icy planetesimals that is believed to surround the Sun at a distance of up to around 100,000 AU (2 ly). This places it in interstellar space, beyond the Sun’s Heliosphere where it defines the cosmological boundary between the Solar System and the region of the Sun’s gravitational dominance. Like the Kuiper Belt and the Scattered Disc, the Oort Cloud is a reservoirs of trans-Neptunian objects, though it is over a thousands times more distant from our Sun as these other two. The idea of a cloud of icy infinitesimals was...
  • T-Minus 12 Days to Perihelion, Rosetta’s Comet Up Close and in 3D

    08/01/2015 11:43:56 AM PDT · by BenLurkin · 9 replies ^ | on August 1, 2015 | Bob King
    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...
  • Alien Life On Philae Comet, Scientists Say

    07/06/2015 5:10:49 PM PDT · by 2ndDivisionVet · 59 replies
    Sky News ^ | July 6, 2015
    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,...
  • Don't Believe the Hype About Life on Philae's Comet

    07/07/2015 10:57:21 AM PDT · by C19fan · 11 replies
    Popular Mechanics ^ | July 6, 2015 | Eric Limer
    You may be hearing some exciting news about comet 67P/Churyumov-Gerasimenko, the place where the Philae lander woke up last month. Astronomer and astrobiologist Chandra Wickramasinghe says that the comet's core might harbor singled-celled extremophile life! But while he could be right, you should take his comments with a comet-sized grain of salt. Wickramashinghe and his colleague Max Wallis made a case for a life-filled comet at this year's Royal Astronomical Society's National Astronomy Meeting in Llandudno, Wales. Wickramasinghe's theory is tied mostly to the cosmic ice ball's structure and black crust. According to Wickramasinghe:
  • Giant sinkholes spotted on Rosetta's comet

    07/01/2015 2:40:21 PM PDT · by BenLurkin · 4 replies
    On average, each of these quasi-circular holes are as wide as two football fields placed together, and some are as deep as the Washington monument is tall. ... The pits can be found clustered in just a few regions on the comet's surface. There are small groups of them on both the "head" and "body" of the rubber-duck-shaped comet, but nearly all of them appear in the comet's northern hemisphere. Cameras on Rosetta's OSIRIS instrument have spotted dust jets shooting out of some of the deeper depressions, but those that are more shallow do not seem to be active. The...
  • Comet Probe Makes Contact After 7 Months Of Silence In Space

    06/15/2015 8:24:00 PM PDT · by nickcarraway · 7 replies
    CBS San Francisco ^ | June 15, 2015
    European scientists are celebrating after receiving a remarkable communication from space. The solar-powered Philae comet probe is sending signals back to earth after seven months of silence. The Philae spacecraft has been in touch with Earth from a speeding comet for the second time since waking up a few days ago, mission control said Monday, and scientists hope to improve communications with the lander by shifting the trajectory of its mother ship. Philae in November became the first spacecraft ever to settle on a comet when it touched down on icy 67P/Churyumov-Gerasimenko, but it managed to send data to Earth...
  • Comet Lander Philae Wakes Up After Months of Hibernation

    06/15/2015 6:39:56 PM PDT · by Swordmaker · 5 replies
    Time Magazine (Video) ^ | June 14, 2015 | Andrew Katz
    The comet lander "spoke" for 85 seconds via its orbiter, "Rosetta" The comet lander that went into hibernation last last year has made contact with its team back on Earth, European space officials said on Sunday. In a brief and excited statement, the European Space Agency said the unmanned Philae, which landed on 67P/Churyumov-Gerasimenko in November to become the first spacecraft to touch down on a comet, sent a number of signals via its orbiter (“Rosetta”) to an operations center in Darmstadt, Germany. They were received on June 13 at 10:28 p.m., local time. Dr. Stephan Ulamec, Philae Project Manager...
  • Philae Wakes Up, Makes Contact!

    06/14/2015 9:19:08 AM PDT · by BenLurkin · 11 replies
    The lander “spoke” with its team on ground via Rosetta for 85 seconds — its first contact since going into hibernation in November. Signals were received at ESA’s European Space Operations Center in Darmstadt at 4:28 p.m. EDT yesterday June 13. The lander sent more than 300 data packets reporting on its condition as well as information about the comet. ... If coming out of hibernation isn’t surprising enough, it appears Philae has been awake for a while because it included historical data along with its current status in those packets. There are still more than 8000 data packets in...
  • Have We Found Rosetta’s Lost Philae Lander?

    06/13/2015 8:05:18 AM PDT · by BenLurkin · 6 replies
    It’s only a bright dot in a landscape of crenulated rocks, but the Rosetta team thinks it might be Philae, the little comet lander lost since November. The Rosetta and Philae teams have worked tirelessly to search for the lander, piecing together clues of its location after a series of unfortunate events during its planned landing on the surface of Comet 67P/Churyumov-Gerasimenko last November 12. ... Rosetta’s navigation and high-resolution cameras identified the first landing site and also took several pictures of Philae as it traveled above the comet before coming down for a final landing. Magnetic field measurements taken...
  • Rosetta’s Comet Keeps On Jetting Even After the Sun Goes Down

    06/08/2015 6:17:02 PM PDT · by BenLurkin · 5 replies ^ | on June 8, 2015 | Jason Major
    Images acquired by the OSIRIS instrument aboard ESA’s Rosetta spacecraft in April 2015 reveal that some of the comet’s dust jets keep on firing even after the Sun has “set” across those regions. This shows that, as the comet continues to approach its August perihelion date, it’s now receiving enough solar radiation to warm deeper subsurface materials. ... Comet 67P and Rosetta (and Philae too!) will come within 185.9 million km of the Sun during perihelion on Aug. 13, 2015 before heading back out into the Solar System.
  • Rosetta Discovery of Surprise Molecular Breakup Mechanism in Comet Coma Alters Perceptions

    06/05/2015 10:40:38 AM PDT · by BenLurkin · 16 replies ^ | June 4, 2015 | Ken Kremer on
    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...
  • OSIRIS discovers balancing rock on 67P

    05/19/2015 4:24:15 PM PDT · by OK Sun · 19 replies
    Max Planck Institute ^ | May 18, 2015 | Max Planck Institute
    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...