Star System
The primary star of the system (component A) is an orange dwarf star that may just have over three fourths the mass of the Sun, about 77 percent of its radius, and only 15.6 percent of its visual luminosity. It has a separation of 190 astronomical units from the binary components B and C, moving in an eccentric orbit that takes at least 2130 years to complete. Gliese 570 A is spectral type K4V and emits X-rays.
A binary system in their own right, components B and C are both rather dim red dwarf stars that have less mass, radius, and luminosity than the Sun. Component B is spectral type M1V, component C is spectral type M3V, and both emit X-rays.
On January 15, 2000, astronomers announced that they had found one of the coolest brown dwarfs then known. Catalogued as Gliese 570 D (or rarely Gliese 570 d), it was observed at a wide separation of more than 1,500 astronomical unit from the triple star system. It has an estimated mass of 50 times that of Jupiter.
The status of Gliese 570 D as a brown dwarf was confirmed by Doppler spectroscopy at the Cerro Tololo Interamerican Observatory in Chile. The surface temperature of this substellar object was found to be a relatively cool 500 degrees Celsius, making it cooler and less luminous than any other known brown dwarf (including the prototype "T" dwarf), and classifying the object as a T7-8V brown dwarf. No X-rays have been reported from this brown dwarf.
Read more about this topic: Gliese 570
Famous quotes containing the words star system, star and/or system:
“Relying on any one disciplinary approach—time-out, negotiation, tough love, the star system—puts the parenting team at risk. Why? Because children adapt to any method very quickly; today’s effective technique becomes tomorrow’s worn dance.”
—Ron Taffel (20th century)
“It is the star to every wand’ring bark,
Whose worth’s unknown, although his height be taken.
Love’s not Time’s fool, though rosy lips and cheeks
Within his bending sickle’s compass come;
Love alters not with his brief hours and weeks,
But bears it out even to the edge of doom.”
—William Shakespeare (1564–1616)
“I have no concern with any economic criticisms of the communist system; I cannot enquire into whether the abolition of private property is expedient or advantageous. But I am able to recognize that the psychological premises on which the system is based are an untenable illusion. In abolishing private property we deprive the human love of aggression of one of its instruments ... but we have in no way altered the differences in power and influence which are misused by aggressiveness.”
—Sigmund Freud (1856–1939)