Orbit and Mass
Gliese 581 b is at minimum about 16 times the Earth's mass, similar to Neptune's mass. It does not transit its star, implying that its inclination is less than 88.1 degrees. Dynamical simulations of the Gliese 581 system assuming that the orbits of the four planets are coplanar show that the system becomes unstable if its component masses exceed 1.6 – 2 times their minimum masses. This is primarily due to the close separation between planets b and e. For Gliese 581 b, the upper mass limit is 30.4 Earth masses, or about 77% more massive than Neptune.
It is rather close to Gliese 581 and completes a full orbit in only 5.4 days at a mean distance of about 6 million kilometres (0.041 AU). By comparison, Mercury is at a distance of 58 million kilometres (0.387 AU) and completes an orbit in 88 days.
Read more about this topic: Gliese 581 B
Famous quotes containing the words orbit and, orbit and/or mass:
“Words can have no single fixed meaning. Like wayward electrons, they can spin away from their initial orbit and enter a wider magnetic field. No one owns them or has a proprietary right to dictate how they will be used.”
—David Lehman (b. 1948)
“Words can have no single fixed meaning. Like wayward electrons, they can spin away from their initial orbit and enter a wider magnetic field. No one owns them or has a proprietary right to dictate how they will be used.”
—David Lehman (b. 1948)
“There are no fixtures in nature. The universe is fluid and volatile. Permanence is but a word of degrees. Our globe seen by God is a transparent law, not a mass of facts. The law dissolves the fact and holds it fluid.”
—Ralph Waldo Emerson (1803–1882)