• The Younger Dryas (YD) was a period of extreme climate change that occurred around 12,900–11,700 years ago. The Younger Dryas (YD) was a period of extreme climate change that occurred around 12,900–11,700 years ago. Younger Dryas: at the end of the Pleistocene era, 12,800 years ago, cosmic impacts triggered an abrupt cooling episode that earth scientists refer to as the Younger Dryas.
  • An international group of investigators has narrowed the date to a 100-year range, sometime between 12,835 and 12,735 years ago. The researchers used Bayesian statistical analyses of 354 dates taken from 30 sites.
  • This range overlaps with that of a platinum peak recorded in the Greenland ice sheet and of the onset of the Younger Dryas climate episode in six independent key records.
  • In order for the major impact theory to be possible, the YDB layer shows to be the same age globally.
  • The era’s dates have been scientifically validated. California and from Venezuela to Canada. Two California sites are on the Channel Islands off Santa Barbara.
  • Radiocarbon dating was used to determine date ranges for each site. They also examined six instances of independently derived age data that used other dating methods.
  • Two core studies taken from the Greenland ice sheet revealed an anomalous platinum layer, a marker for the YDB. A study of tree rings in Germany also showed evidence of the YDB, as did freshwater and marine varves, the annual laminations that occur in bodies of water. Even stalagmites in China displayed signs of abrupt climate change around the time of the Younger Dryas cooling event. The records suggest a causal connection between the YDB cosmic impact event and the Younger Dryas cooling event that caused this anomalous and enigmatic cooling.
  • The Younger Dryas onset was not fully synchronized; in the tropics, the cooling was spread out over several centuries, and the same was true of the early-Holocene warming.[1] Even in the Northern Hemisphere, temperature change was highly seasonal, with much colder winters and cooler springs, yet no change or even slight warming during the summer.[6][7] Substantial changes in precipitation also took place, with cooler areas experiencing substantially lower rainfall, while warmer areas received more of it.
  • OUR CURRENT MOON IS THE NEW KID ON THE BLOCK. THE YOUNGER DRYAS ERA SHOWED THAT THE FIRST MOON WAS NOT ADEQUATE TO DO THE JOB OF KEEPING THE WORD STAPLE AND IN SYNC.
  • The Moon is Earth’s only natural satellite. It orbits at an average distance of 384,400 km, about 30 times the diameter of Earth. Tidal forces between Earth and the Moon have synchronized the Moon’s orbital period with its rotation period at 29.5 Earth days, causing the same side of the Moon to always face Earth. Wikipedia
  • Characteristics of the Earth-Moon system:
  • The Moon and Earth exert strong gravitational influence on each other, forming a system having distinct properties and behaviors of its own.

  • The two bodies orbit each other about a common center of mass. The barycenter, rather than the center of Earth, that follows an elliptical path around the Sun in accord with Kepler’s laws of planetary motion. The distance between the Moon and Earth varies rather widely because of the combined gravity of Earth, the Sun, and the planets. It orbits nearer Earth and slower in the part farther away.

  • Every highland region is heavily cratered—evidence for repeated collisions with large bodies.
  • The survival of similar large impact structures on Earth is relatively rare because of Earth’s geologic activity and weathering. Olcanic activity has occurred within the Moon, but the results are mostly quite different from those on Earth. The ancient far-side highlands are scarred by huge basins, but these basins are not filled with lava.
  • On a small-to-microscopic scale, the properties of the lunar surface are governed by a combination of phenomena—impact effects the arrival, at speeds up to tens of kilometers per second, of meteoritic material ranging in size down to fractions of a micrometer; bombardment by solar wind, cosmic ray, and solar flare particles; ionizing radiation; and temperature extremes.
  • The materials formed of these minerals are classified into four main groups: asaltic volcanism, the rocks forming the marina, pristine highland rocks uncontaminated by impact mixing, breccias and impact melts, formed by impacts that disassembled and reassembled mixtures of rocks, and soils, defined as unconsolidated aggregates of particles less than 1 cm (0.4 inch) in size, derived from all the rock types. All these materials are of igneous origin, but their melting and crystallization history is complex.
  • The idea that the lunar crust is the product of differentiation in an ancient magma ocean is supported to some extent by compositional data, which show that lightweight rocks, containing such minerals as plagioclase, rose while denser materials, such as pyroxene and olivine, sank to become the source regions for the later radioactive heating episode that resulted in the outflows of mare basalts. Whether there ever was a uniform global ocean of molten rock, it is clear that the Moon’s history is one of much heating and melting in a complex series of events that would have driven off volatiles (if any were present) and erased the record of earlier mineral compositions.

    the Moon as a body in which, given its small size, all heat-driven internal processes have run down. With the rise of scientific inquiry in the Renaissance, investigators attempted to fit theories on the origin of the Moon to the available information, and the question of the Moon’s formation became a part of the attempt to explain the observed properties of the solar system (see Solar system: Origin of the solar system). At first, the approach was largely founded on a mathematical examination of the dynamics of the Earth-Moon system. Rigorous analysis of careful observations over a period of more than 200 years gradually revealed that, because of tidal effects (see tide), the rotations of both the Moon and Earth are slowing and the Moon is receding from Earth. Studies then turned back to consider the state of the system when the Moon was closer to Earth. Throughout the 17th, 18th, and

  • The solar wind has implanted hydrogen, helium, and other elements in the surfaces of fine grains of lunar soil. Though their amounts are small—they constitute about 100 parts per million in the soil—they may someday serve as a resource. They are easily released by moderate heating, but large volumes of soil would need to be processed to obtain useful amounts of the desired materials. Helium-3, a helium isotope that is rare on Earth and that has been deposited on the Moon by the solar wind, has been proposed as a fuel for nuclear fusion reactors in the future.