A Hubble picture of a star-forming cloud of dust and gas called the Orion Nebula.
Image courtesy ESA/NASA
Image courtesy ESA/NASA
Stars like the sun typically form in clusters with other stars. Many clusters are spread out so that the stars drift apart, but others are denser, and gravity keeps their stars close together.
The sun now stands alone, so astronomers think our star—and its newborn solar system—was either ejected from its birth cluster or drifted away from its siblings about 4.5 billion years ago.
Messier 67, or M67, is a hundred-light-year-wide ball of stars that recently passed some crucial "paternity tests" for being the sun's birthplace.
The cluster not only harbors stellar bodies similar in temperature, age, and chemistry to our sun, but M67 also drifts a relatively close 2,900 light-years away.
A new study of M67, however, undermines the existing lines of evidence and leaves almost no chance that our star could hail from the region.
(Also see "Three Theories of Planet Formation Busted, Expert Says.")
Computer simulations show that a rare chain of events—two or three massive stars lining up just right to make a gravitational slingshot—would have been needed to kick the sun out of M67 and get it where it is today.
Such a powerful event is a probabilistic Hail Mary and, even if it had occurred, the speed of the kick would have ripped our nascent solar system to shreds.
"When you have that kind of gravitational disruption, planetary disks evaporate, and existing planets acquire energy and can be expelled," said study leader Barbara Pichardo, an astrophysicist at the National Autonomous University of Mexico. more here
The cluster not only harbors stellar bodies similar in temperature, age, and chemistry to our sun, but M67 also drifts a relatively close 2,900 light-years away.
A new study of M67, however, undermines the existing lines of evidence and leaves almost no chance that our star could hail from the region.
(Also see "Three Theories of Planet Formation Busted, Expert Says.")
Computer simulations show that a rare chain of events—two or three massive stars lining up just right to make a gravitational slingshot—would have been needed to kick the sun out of M67 and get it where it is today.
Such a powerful event is a probabilistic Hail Mary and, even if it had occurred, the speed of the kick would have ripped our nascent solar system to shreds.
"When you have that kind of gravitational disruption, planetary disks evaporate, and existing planets acquire energy and can be expelled," said study leader Barbara Pichardo, an astrophysicist at the National Autonomous University of Mexico. more here
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