Orbit and Mass
47 Ursae Majoris b orbits at a distance of 2.10 AU from its star, taking 1,078 days or 2.95 years to complete a revolution. It was the first long-period planet around a main sequence star to be discovered. Unlike the majority of known long-period extrasolar planets, the eccentricity of the orbit of 47 Ursae Majoris b is low.
A limitation of the radial velocity method used to detect 47 Ursae Majoris b is that only a lower limit on the planet's mass can be obtained. Preliminary astrometric measurements made by the Hipparcos satellite suggest the planet's orbit is inclined at an angle of 63.1° to the plane of the sky, which would imply a true mass 12% greater than the lower limit determined by radial velocity measurements. However, subsequent investigation of the data reduction techniques used suggests that the Hipparcos measurements are not precise enough to adequately characterise the orbits of substellar companions, and the true inclination of the orbit (and hence the true mass) are regarded as unknown.
Read more about this topic: 47 Ursae Majoris 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)
““To my thinking” boomed the Professor, begging the question as usual, “the greatest triumph of the human mind was the calculation of Neptune from the observed vagaries of the orbit of Uranus.”
“And yours,” said the P.B.”
—Samuel Beckett (1906–1989)
“No doubt Jews are most obnoxious creatures. Any competent historian or psychoanalyst can bring a mass of incontrovertible evidence to prove that it would have been better for the world if the Jews had never existed. But I, as an Irishman, can, with patriotic relish, demonstrate the same of the English. Also of the Irish.... We all live in glass houses. Is it wise to throw stones at the Jews? Is it wise to throw stones at all?”
—George Bernard Shaw (1856–1950)