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Earth Lost Significant Portion of Atmosphere to Moon, New Study Suggests

VOA News

   New research suggests that the collision of space objects that created
   Earth's moon may have robbed it of 10% to 60% of its original
   atmosphere.

   Most scientists believe that about 4 billion years ago when Earth was
   still developing, a massive object the size of Mars hit the planet,
   sending vaporized particles from the collision into space, which were
   then bound together through gravity to form Earth's moon.

   The so-called "impact hypothesis" is one of three key theories of the
   moon's formation. The others suggest the moon was either formed at the
   same time as Earth, or that it was captured by Earth's gravitational
   field as it traveled through space.

   In the new study published Wednesday in the Astrophysical Journal
   Letters, researchers focused on the impact theory, and ran more than
   300 computer simulations of massive object collisions with rocky
   planets with thin atmospheres like Earth.

   The scientists factored in the angle at which the objects hit the
   planet, the speed of the impact, as well as the size and mass of the
   colliding object.

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