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Recently, scientists have confidence in the unmistakable presence of the asteroid belt around nearest to our Sun stars VEGA and Fomalhaut. These data are the result of long and hard work of the space-based telescopes "Spitzer" and "Herschel". There is an assumption that some of these stars may have planetary systems similar to the Sun.
VEGA is a young star, if you compare it with the Sun. The metallicity this light is low, which means that it includes very few elements heavier than helium. The VEGA is logged variability glow, but whether it is a variable star is not exactly known. This beautiful star in the Northern sky, shining so bright and confident, surrounded by a dust disk detected by the intensity of its infrared radiation.
Radiation was much stronger theoretical assumptions, this means that around VEGA rotating disk of dust and heated. And since there is a disk, it can be generated by collisions of small bodies of comets and asteroids surrounded by VEGA. Data from the infrared telescope CHARA at the Observatory mount Wilson in 2006 helped to identify the second disk of dust around VEGA at a distance of 8 a. that is, from the star, that is, in a trillion miles away.
This dust is similar to the solar belt of asteroids and can also be potentially emerging planet. Analogue in the Solar system serves us well and the Kuiper belt, is widely bordering the Solar system periphery.
The difference VEGA from the Sun that it is much faster turns around its axis of rotation speed at the equator equal 274 km/s! The Sun as such, is about 2 km/S. because Of this rapid movement VEGA became the ellipsoid of rotation, its scope flattened at the poles, and the polar region the hot Equatorial. From Earth, the astronomers looking at VEGA, watching her from the pole, and to the naked eye we see exceptional beauty silver-blue star, praised by poets and favorite observers in the Northern hemisphere of the Earth.
Equally interesting for us and Fomalhaut (or alpha of southern Pisces)is the brightest star in the constellation, and one of the brightest stars in the night sky. Fomalhaut is also surrounded by a disk of cosmic dust toroidal shape with a distinct inner border, the disc is tilted at an angle of 24 degrees. This belt of cosmic dust dostigaet width-25 a. E.; and the geometrical center of the dust belt is located at 15. that is, from the very Fomalgaut, he is also analogous to the Kuiper belt in our Solar system.
Disk Fomalhaut considered protoplanetary, it emits infrared radiation, as a disc VEGA, and is in addition protoplanetary: attalinata Fomalhaut b was calculated when analyzing the distribution of cosmic dust around Fomalhaut in 1998, and November 13, 2008 NASA issued a press release stating that as a result of comparison of images taken in 2004 and 2006, was visually proved the existence of extrasolar planets.
The mass of the planet is about 3 Jupiter masses, it can become heavier, absorbing substance disk. Later this hypothesis has been challenged: in 2011-2012 astrophysics of Florida University in the U.S. and scientists project Atacama Large Millimeter Array suggested at least two planets:Fomalhaut Fomalhaut b and c. The weight of both planets lying in the interval from the mass of Mars to a few Earth masses.
According to calculations disk of dust must be much greater because of the stellar wind of Fomalhaut, repulsive particles out. According to the Observatory Herschel, it is assumed that the disc has such a small size because of the constant updating by shrapnel from a very frequent collisions icy comets with larger bodies in orbit of Fomalhaut (up to a thousand a day). Such a number of impacts are predicted to be present in comets belt from 1011 to 1014 comets, which is a similar quantity, intended for the Oort Cloud in our Solar system.
Locking the movement of celestial bodies, similar in age and properties, as well as moving in a similar way, astronomers was moving star group of castor, which includes Fomalhaut. He is accompanied by a dull flashing star TW southern Pisces, located at a distance of one light year from Fomalhaut. These two objects can be considered as the stars companion, that is, they could be from one star cluster.
The similarity of the systems of VEGA and Fomalhaut that these two luminaries have internal warm and external cold zones, analogues of the asteroid belt and the Kuiper belt in our Solar system. This evidence suggests scientists that many exoplanets may exist, and must be detected with time. So familiar to us Solar system povtorim in many countless options in the Universe!
VEGA and Fomalhaut star twins in many respects. Both objects is approximately twice more massive than the Sun, so they are hot and blue. They are our neighbors in the Universe, they are about 25 light years from Earth. They are only a few hundred million years: Fomalhaut 400 million, and VEGA little more - about 600 million years.
Extremely important today is that "Herschel" and "the Spitzer" registered infrared warm and cold dust in the form of two discrete zones around VEGA and Fomalhaut. This confirmed the data of previous studies that establishes the truth: discovered the asteroid belt around VEGA and Fomalhaut. It is essential that the visible part of the spectrum to see the asteroids impossible - too bright star light.
The belt is much heavier than their counterparts in the Solar system, as VEGA and Fomalhaut - more young stars formed from huge compared to the sun, clouds of gas and dust. The presence of the interval between the inner and outer belts our neighbors VEGA and Fomalhaut perfectly match the proportions of the Solar system, and the distance between the asteroid belt and those Kuiper we have is that the outer belt is about 10 times farther from the star than internal. This gap can be placed to the family of planets, such as Jupiter, or similar to those described the family of the star HR 8799, which is known for four planets in the gap between similar zones.
Astronomers expect the launch of a space telescope "James Webb", which is scheduled for 2015. It is linked to hopes for discovery of the search for exoplanets.
Tatiana Valchuk