Keyword: lunarcapture

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  • Quake split a tectonic plate in two, and geologists are shaken

    10/29/2018 3:08:28 PM PDT · by ETL · 21 replies
    National Geographic ^ | Oct 24, 2018 | Robin George Andrews
    An intense temblor in Mexico was just the latest example of an enigmatic type of earthquake with highly destructive potential On September 7, 2017, a magnitude 8.2 earthquake struck southern Mexico, killing dozens and injuring hundreds. While earthquakes are common enough in the region, this powerful event wasn’t any run-of-the-mill tremor. That’s because part of the roughly 37-mile-thick tectonic plate responsible for the quake completely split apart, as revealed by a new study in Nature Geoscience. This event took place in a matter of tens of seconds, and it coincided with a gargantuan release of energy. “If you think of...
  • The Moon's equatorial bulge hints at Earth's early conditions

    02/15/2018 9:44:00 PM PST · by SunkenCiv · 19 replies
    Astronomy ^ | Tuesday, February 13, 2018 | Amber Jorgenson
    Over two centuries ago, Pierre-Simon Laplace, a French physicist and mathematician, noticed that the Moon's equatorial bulge is about 20 times larger than expected. Now, researchers are trying to find out why. Although the Moon looks quite spherical from the ground, it is flatter at its poles and wider at its equator, a trait known as an equatorial bulge. This characteristic is common; it's usually caused by an object's rotation around its axis. However, it's been noted that the Moon's bulge is about 20 times larger than it should be given its rotational rate of once per month... researchers at...
  • Free-floating planets in the Milky Way outnumber stars by factors of thousands

    05/10/2012 10:10:10 AM PDT · by LibWhacker · 103 replies
    Springer ^ | 5/10/12
    Researchers say life-bearing planets may exist in vast numbers in the space between stars in the Milky WayA few hundred thousand billion free-floating life-bearing Earth-sized planets may exist in the space between stars in the Milky Way. So argues an international team of scientists led by Professor Chandra Wickramasinghe, Director of the Buckingham Centre for Astrobiology at the University of Buckingham, UK. Their findings are published online in the Springer journal Astrophysics and Space Science. The scientists have proposed that these life-bearing planets originated in the early Universe within a few million years of the Big Bang, and that...
  • Astronomy Picture of the Day -- Evolution of the Moon [ video ]

    03/20/2012 8:25:49 PM PDT · by SunkenCiv · 10 replies
    NASA ^ | March 20, 2012 | (see photo credit)
    Explanation: What is the history of the Moon? The Moon was likely created from debris expelled when a Mars-sized object violently impacted the Earth about 4.5 billion years ago. Just after gravitationally condensing, as imagined above, the glowing-hot surface of the Moon cooled and cracked. Rocks large and small continued to impact the surface, including a particularly large impact that created Aitken Basin about 4.3 billion years ago. A Heavy Bombardment period then continued for hundreds of millions of years, creating large basins all over the lunar surface. Over the next few billion years lava flowed into Earth-side basins, eventually...
  • Earth and Venus are the Same Size, so Why Doesn’t Venus Have a Magnetosphere?....

    12/12/2017 10:53:55 AM PST · by BenLurkin · 54 replies
    universetoday.com ^ | universetoday.com | Matt Williams
    According to a new study conducted by an international team of scientists, it may have something to do with a massive impact that occurred in the past. Since Venus appears to have never suffered such an impact, its never developed the dynamo needed to generate a magnetic field. ... According to the most widely-accepted models of planet formation, terrestrial planets are not formed in a single stage, but from a series of accretion events characterized by collisions with planetesimals and planetary embryos – most of which have cores of their own. Recent studies on high-pressure mineral physics and on orbital...
  • Heavenly Bodies Stir Up Routine Catastrophes

    03/18/2003 9:33:33 AM PST · by blam · 9 replies · 842+ views
    IOL ^ | 3-18-2003 | Graeme Addison
    Heavenly bodies stir up routine catastrophes March 18 2003 at 01:30PM By Graeme Addison Legend has it that when two people get together and er... bond, the Earth will move – at least in a metaphorical sense. Likewise, it takes two heavenly bodies, an impactor and a target, to come together with Earth-shattering force to form a crater. There’s nothing dreamlike about this: it happens, frequently, throughout the solar system. Impact catastrophes are routine. Just over two-billion years ago, a chunk of asteroid at least the size of Table Mountain struck the landmass that is now South Africa. It hurtled...
  • 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...
  • Large Meteorite Impacts and Planetary Evolution V

    01/10/2016 4:36:03 PM PST · by SunkenCiv · 20 replies
    EurekAlert! ^ | January 8, 2016 | Geological Society of America
    Impact cratering is one of the most fundamental geological processes. On many planets, impact craters are the dominant geological landform. On Earth, erosion, plate tectonics, and volcanic resurfacing continually destroy the impact cratering record, but even here, the geological, biological, and environmental effects of impact cratering are apparent. Impact events are destructive and have been linked to at least one of the 'big five' mass extinctions over the past 540 million years. Intriguingly, impact craters can also have beneficial effects. Many impact craters are associated with economic metalliferous ore deposits and hydrocarbon reservoirs. This Special Paper from The Geological...
  • Source of Moon's Magnetism Found

    01/15/2009 8:15:48 PM PST · by Gordon Greene · 46 replies · 1,170+ views
    Yahoo.com ^ | 01-15-2009 | SPACE.com Staff
    Moon rocks delivered to Earth by Apollo astronauts held a mystery that has plagued scientists since the 1970s: Why were the lunar rocks magnetic? Earth's rotating, iron core produces the planet's magnetic field. But the moon does not have such a setup. Now, scientists at MIT think they have a solution. Some 4.2 billion years ago, the moon had a liquid core with a dynamo (like Earth's core today) that produced a strong magnetic field. The moon's magnetic field would have been about 1-50th as strong as Earth's is today, the researchers say. The MIT team found evidence for the...
  • Astrobiology Top 10: Earth's Moon May Not Be Critical to Life

    12/25/2015 12:03:24 PM PST · by SunkenCiv · 44 replies
    Astrobiology ^ | Wednesday, December 23, 2015 | Keith Cooper
    In 1993, French astronomer Jacques Laskar ran a series of calculations indicating that the gravity of the Moon is vital to stabilizing the tilt of our planet. Earth's obliquity, as this tilt is technically known as, has huge repercussions for climate. Laskar argued that should Earth's obliquity wander over hundreds of thousands of years, it would cause environmental chaos by creating a climate too variable for complex life to develop in relative peace. So his argument goes, we should feel remarkably lucky to have such a large moon on our doorstep, as no other terrestrial planet in our solar system...
  • Comet or Meteorite Impact Events in 1178AD?

    01/03/2005 3:59:02 PM PST · by blam · 67 replies · 5,613+ views
    SIS Conference ^ | 1-26-2003 | Emilio Spedicato
    1. Introduction As related by Clube and Napier in their monograph The Cosmic Winter, see [1], in the year 1178 A.D. four wise men of Canterbury were sitting outside on a clear and calm 18th June night, a half Moon standing placidly in the starry sky. Suddenly they noticed a flame jutting out of a horn of the Moon. Then they saw the Moon tremble and its colour change slowly from light brilliant to a darker reddish tone. Such a colour remained for all the time the Moon was visible during that phase. This story is found in a manuscript...
  • Crystal is 'oldest scrap of Earth crust'

    02/24/2014 7:56:24 AM PST · by JoeProBono · 50 replies
    bbc ^ | 24 February 2014
    A tiny 4.4-billion-year-old crystal has been confirmed as the oldest fragment of Earth's crust. The zircon was found in sandstone in the Jack Hills region of Western Australia. Scientists dated the crystal by studying its uranium and lead atoms. The former decays into the latter very slowly over time and can be used like a clock. The finding has been reported in the journal Nature Geoscience. Its implication is that Earth had formed a solid crust much sooner after its formation 4.6 billion years ago than was previously thought, and very quickly following the great collision with a Mars-sized body...
  • Gondwana Supercontinent Underwent Massive Shift During Cambrian Explosion

    08/11/2010 5:32:45 AM PDT · by decimon · 51 replies · 1+ views
    Yale University ^ | August 10, 2010 | Unknown
    New Haven, Conn. — The Gondwana supercontinent underwent a 60-degree rotation across Earth’s surface during the Early Cambrian period, according to new evidence uncovered by a team of Yale University geologists. Gondwana made up the southern half of Pangaea, the giant supercontinent that constituted the Earth’s landmass before it broke up into the separate continents we see today. The study, which appears in the August issue of the journal Geology, has implications for the environmental conditions that existed at a crucial period in Earth’s evolutionary history called the Cambrian explosion, when most of the major groups of complex animals rapidly...
  • Why is the Earth moving away from the sun?

    06/01/2009 6:59:33 PM PDT · by SunkenCiv · 70 replies · 1,636+ views
    New Scientist ^ | Monday, June 1, 2009 | Kelly Beatty, Sky and Telescope
    Skywatchers have been trying to gauge the sun-Earth distance for thousands of years. In the third century BC, Aristarchus of Samos, notable as the first to argue for a heliocentric solar system, estimated the sun to be 20 times farther away than the moon. It wasn't his best work, as the real factor is more like 400. By the late 20th century, astronomers had a much better grip on this fundamental cosmic metric -- what came to be called the astronomical unit. In fact, thanks to radar beams pinging off various solar-system bodies and to tracking of interplanetary spacecraft, the...
  • The Curious Case of Missing Asteroids

    03/03/2009 7:31:32 PM PST · by SunkenCiv · 38 replies · 720+ views
    NASA Solar System Exploration ^ | February 25, 2009 | Lori Stiles
    University of Arizona scientists have uncovered a curious case of missing asteroids. The main asteroid belt is a zone containing millions of rocky objects between the orbits of Mars and Jupiter. The scientists find that there ought to be more asteroids there than researchers observe. The missing asteroids may be evidence of an event that took place about 4 billion years ago, when the solar system's giant planets migrated to their present locations. UA planetary sciences graduate student David A. Minton and UA planetary sciences professor Renu Malhotra say missing asteroids is an important piece of evidence to support an...
  • Planets Around Planets?

    06/05/2006 7:32:33 PM PDT · by KevinDavis · 6 replies · 359+ views
    Sky and Telescope ^ | 06/05/06 | Robert Naeye
    June 5, 2006 | Evidence continues to mount that planets can form around very-low-mass objects. In fact, planets might even form around objects that are so low in mass that they themselves could be considered "planets." The latest results, reported at this week's American Astronomical Society meeting in Calgary, Alberta, come from groups led by Ray Jayawardhana (University of Toronto, Canada) and Subhanjoy Mohanty (Harvard-Smithsonian Center for Astrophysics).
  • The Moon may have formed in a nuclear explosion

    01/30/2010 12:03:32 AM PST · by LibWhacker · 30 replies · 787+ views
    PhysOrg ^ | 1/28/10 | Lin Edwards
    (PhysOrg.com) -- A new theory suggests the Moon was formed after a natural nuclear explosion in the Earth's mantle rather than after the impact of a massive object with the Earth, as previously thought. The problem with the impact hypothesis is that simulations calculate the Moon should be composed of 80% impactor and 20% Earth, whereas in fact the isotope ratios of light and heavy elements found in Moon rocks so far examined are virtually identical to those on Earth. The fission hypothesis is an alternative explanation for the formation of the moon, and it predicts similar isotope ratios in...
  • Moon Not Only Has Water, but Lots of It

    10/21/2010 12:05:30 PM PDT · by Fractal Trader · 19 replies
    Wall Street Jounal ^ | 21 October 2010 | GAUTAM NAIK
    Scientists have discovered significant amounts of water on the moon—about twice the quantity seen in the Sahara Desert—a finding that may bolster the case for establishing a manned base on the lunar surface. In an audacious experiment last year, the National Aeronautics and Space Administration slammed a spent-fuel rocket into a lunar crater at 5,600 miles an hour, and then used a pair of orbiting satellites to analyze the debris thrown off by the impact. They discovered that the crater contained water in the form of ice, plus a host of other resources, including hydrogen, ammonia, methane, mercury, sodium and...
  • Water on the Moon: a Billion Gallons

    10/22/2010 11:23:14 AM PDT · by ColdOne · 38 replies · 2+ views
    ABC News ^ | Oct 21, 2010 | NED POTTER
    Water on the moon? Scientists used to think it was as dry as, well, lunar dust. But after a year of analysis NASA today announced that its LCROSS lunar-impact probe mission found
  • Where on Earth has our water come from?

    10/25/2010 6:37:55 PM PDT · by SunkenCiv · 38 replies
    Highlights in Chemical Science ^ | Friday October 22, 2010 | Rebecca Brodie
    Evidence that water came to Earth during its formation from cosmic dust, rather than following later in asteroids, has been shown by a group of international scientists. The origin of the abundant levels of water on Earth has long been debated with the main differences in the theories being the nature of the material that carries the water, and whether the water came during or after planet formation. Now, Nora de Leeuw at University College London, UK, and colleagues have used molecular-level calculations to prove that dissociative chemisorption of water onto the surface of olivine rich minerals, such as forsterite,...