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Keyword: comets

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  • A close call of 0.8 light years [Nibiru?]

    02/22/2015 7:43:37 AM PST · by Red Badger · 38 replies
    Phys.Org ^ | Provided by University of Rochester
    A group of astronomers from the US, Europe, Chile and South Africa have determined that 70,000 years ago a recently discovered dim star is likely to have passed through the solar system's distant cloud of comets, the Oort Cloud. No other star is known to have ever approached our solar system this close - five times closer than the current closest star, Proxima Centauri. In a paper published in Astrophysical Journal Letters, lead author Eric Mamajek from the University of Rochester and his collaborators analyzed the velocity and trajectory of a low-mass star system nicknamed "Scholz's star." The star's trajectory...
  • Star Blasted Through Solar System 70,000 Years Ago

    02/18/2015 1:11:46 PM PST · by BenLurkin · 113 replies
    discovery.com ^ | Ian O'Neill
    Highlighted by astronomers at the University of Rochester and the European Southern Observatory, the star — nicknamed “Scholz’s star” — has a very low tangential velocity in the sky, but it has been clocked traveling at a breakneck speed away from us. In other words, from our perspective, Scholz’s star is fleeing the scene of a collision with us. “Most stars this nearby show much larger tangential motion,” said Eric Mamajek, of the University of Rochester. “The small tangential motion and proximity initially indicated that the star was most likely either moving towards a future close encounter with the solar...
  • A star disturbed the comets of the solar system 70,000 years ago

    03/20/2018 8:40:10 PM PDT · by BenLurkin · 59 replies
    sciencedaily.com ^ | March 20, 2018 | FECYT - Spanish Foundation for Science and Technology
    Scholz's star -- named after the German astronomer who discovered it -- approached less than a light-year from the Sun. Nowadays it is almost 20 light-years away, but 70,000 years ago it entered the Oort cloud, a reservoir of trans-Neptunian objects located at the confines of the solar system. ... Now two astronomers from the Complutense University of Madrid, the brothers Carlos and Raúl de la Fuente Marcos, together with the researcher Sverre J. Aarseth of the University of Cambridge (United Kingdom), have analyzed for the first time the nearly 340 objects of the solar system with hyperbolic orbits (very...
  • Rosetta’s 67P Is The Result Of A Collision Of Two Comets

    03/09/2018 9:41:33 AM PST · by BenLurkin · 1 replies
    Universe Today ^ | March 9, 2018 | Evan Gough
    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)...
  • Rare Comet Visiting Inner Solar System For The First Time To Be Visible From Earth This January

    01/03/2017 8:35:33 PM PST · by BenLurkin · 46 replies
    Tech Times ^ | 3 January 2017, 5:47 am EST | Allan Adamson
    Seeing Comet C/2016 U1 NEOWISE fly by would be a rare opportunity for skygazers because the celestial body won't likely pass by Earth for the next thousands of years. Unlike short period comets such as Halley's, a comet which passes by our planet every 75 to 80 years, it would take C/2016 U1 NEOWISE far longer time before it gets to visit this region of the solar system again. ... Paul Chodas, from NASA's Center for Near-Earth Object (NEO) Studies, said that there is a good chance that the object will be visible from Earth using a good pair of...
  • Centaurs Keep Their Rings From Greedy Gas Giants

    06/26/2016 10:36:02 AM PDT · by BenLurkin · 14 replies
    universetoday.com ^ | 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
    phys.org ^ | 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
    Space.com ^ | October 28, 2015 | Mike Wall - Space.com 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...