Astronomers have determined the exact distance to the object Cygnus X-1, which was the first object recognized as the black hole. Cygnus X-1or Cyg X-1 is the X-ray source in the constellation Cygnus, which opened in 1964. Astronomers have calculated the mass of the black hole in the constellation Cygnus, focusing on the characteristics of its interaction with the blue supergiant. Studing new data, collected by an array of radio telescopes Very Long Baseline Array, astronomers able to determine the distance from Earth to Cygnus X-1, that proved equal to 6050 light years, plus or minus 400 light-years.
According to the calculations of astronomers, the mass of blue supergiant in this case should be 19 times more than the mass of the sun, and the mass of the X-ray source should be 14.8 times more than the solar mass. The new value of mass is more greater than the critical limit, which separates the neutron star and the black hole. So, in this new work presents evidence that the very first black hole really is such.