Astronomy News

Universe Today has a number of interesting stories.

Evidence of Asteroid Impact For Sodom and Gomorrah?: "A Cuneiform clay tablet that has puzzled researchers for over 150 years is now believed to describe an asteroid impact in 3123 BC in Austria. Researchers believe the tablet, which seemingly describes a cataclysmic event, may account for the biblical tale of Sodom and Gomorrah."

What is the Biggest Star in the Universe?: "The largest known star is VY Canis Majoris; a red hypergiant star in the constellation Canis Major, located about 5,000 light-years from Earth. University of Minnesota professor Roberta Humphreys recently calculated its upper size at more than 2,100 times the size of the Sun. Placed in our Solar System, its surface would extend out past the orbit of Saturn. Light takes more than 8 hours to cross its circumference!"

A Case of MOND Over Dark Matter: "According to Newton's Second Law of Dynamics, objects on the farthest edges of galaxies should have lower velocities than objects near the center. But observations confirm that galaxies rotate with a uniform velocity. Some astronomers believe the orbital behavior of galaxies can be explained more accurately with Modified Newtonian Dynamics (MOND) — a modified version of Newton's Second Law — than by the rival, but more widely accepted, theory of dark matter. The dark matter theory assumes that a halo of dark matter surrounds each galaxy, providing enough matter (and gravity) that all the stars in a galaxy disc orbit with the same velocity. MOND, however uses a different explanation, and a recent study of eight dwarf galaxies that orbit the Milky Way seems to favor the MOND approach over the dark matter theory." "Even without direct detection, the dark matter theory is difficult to prove or refute and although we may not be able to prove whether MOND is correct, by carrying out these kind of tests we can see if it continues to hold up or if it is definitely ruled out," said Angus.