For the first time, scientists have been able to take a direct (X-Ray) picture of a binary star. The stellar pair (pictured using the Chandra telescope) is some 420 light years away from us. The distance between the stars (Mira A and B) is about twice the distance between Pluto and the Sun.
Mira A is a highly evolved red giant star. Mira B is a white dwarf. Mira A is losing gas rapidly from its upper atmosphere via a stellar wind. Mira B exerts a gravitational tug that creates a gaseous bridge between the two stars. Gas from the wind and bridge accumulates in an accretion disk around Mira B and collisions between rapidly moving particles in the disk produce X-rays.
Mira B (left) and A (Courtesy: Chandra)
Mira A (or simply, Mira) was named "The Wonderful" star in the seventeenth century because its brightness was observed to wax and wane over a period of about 330 days. In this advanced red giant phase of Mira A's life, its diameter has swollen to about 600 times that of the Sun and it is pulsating, due to increasingly energetic nuclear reactions in its core.
X-ray studies of the Mira star system may also provide better understanding of interactions between other binary star systems consisting of a "normal" star and a collapsed star such as a white dwarf, black hole or a neutron star.
Mira A is a highly evolved red giant star. Mira B is a white dwarf. Mira A is losing gas rapidly from its upper atmosphere via a stellar wind. Mira B exerts a gravitational tug that creates a gaseous bridge between the two stars. Gas from the wind and bridge accumulates in an accretion disk around Mira B and collisions between rapidly moving particles in the disk produce X-rays.
Mira B (left) and A (Courtesy: Chandra)
Mira A (or simply, Mira) was named "The Wonderful" star in the seventeenth century because its brightness was observed to wax and wane over a period of about 330 days. In this advanced red giant phase of Mira A's life, its diameter has swollen to about 600 times that of the Sun and it is pulsating, due to increasingly energetic nuclear reactions in its core.
X-ray studies of the Mira star system may also provide better understanding of interactions between other binary star systems consisting of a "normal" star and a collapsed star such as a white dwarf, black hole or a neutron star.
Interacting Stars
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14 Comments:
Neelima: Sorry I didnt mean it that way... I know you did it by choice :-). And of course, you can always start learning new things :):):):).
But sometimes, one of the stars become a parasite, like in this post...... feeding stuff from its partner...
Hmmm.. multi-stars :):):). Systems with more than two stars are rare, since the gravitational interactions are not always very stable, and even small fluctuations can push two (or more) of the stars to collide and merge. But there are some examples of such stars, as you might know:
Alpha Centauri: A triple star system: but Alpha Centauri A and B form a binary pair, whereas C is a red dwarf far far away (4.22 light years). Such configurations are gravitationally stable, since from a stability point of view, this is similar to two binary systems (A and B, AB and C).
Alcyone: Four-star system - consisting of two binary pairs orbiting at a large distance from each other (stable configuration) in the Pleiades contellation.
Castor: Six-star - but composed of four binary sub-systems... one of the brightest stars in the night.
It has not yet been possible to directly photograph these stars, esp. because the stars are very close to each other, and often one of the stars is very small (a white dwarf, or a black hole, in case of Sirius). But surely, newer and better telescopes will be able to find more about them :):).
and diameter 600 times that of sun amd distance betn 2 twice the dis of sun and pluto,
phewwwwwww :)
but i still didnt understand why the 2 stars would be differently evolved. is it because i havent still comprehended the binary star part?
The evolution of stars depend upon their mass. Lighter stars live longer (as they burn the hydrogen much slower), like our Sun. Heavier stars burn faster, and die younger.
When the fuel is nearly finished, stars go through a red-giant stage when they bloat to a huge size (Sun will bloat like that after some 5 billion years). After that, lighter stars (like Sun) become a white dwarf, as the outer layers of the red-giant dissipate. Heavier stars end up as neutron stars, or black holes (after blowing their outer layers with a supernova explosion).
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