Where is cygnus x 1

The conspicuous Northern Cross asterism forming the main outline of Cygnus is the key to easily isolating a specific part of the sky from which to begin our star-hop. First, note the central star of the cross, magnitude 2. Second, pick out magnitude 3. Third, locate the brightest star roughly mid-way along the line joining Albireo and Sadr — it actually lies a bit off the middle of this imaginary line, closer to Sadr than Albireo.

This is Eta Cygni, magnitude 3. The black hole has a binary companion, though: a magnitude 9. The photograph on page clearly identifies HDE with a small ring encircling the star, a great help due to the fairly close proximity of another star of similar color and brightness.

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Jon Lomberg Milky Way Posters. Astronomy for Kids. Sign up. Table of Contents Subscribe Digital Editons. Discovered in , it is one of the most studied objects in its class. It is also one of the strongest persistent X-ray sources known. Cygnus X-1 has a mass Cygnus X-1 has an event horizon with a radius of around 44 kilometres.

The event horizon is the region of space around a black hole with a gravitational field strong enough to prevent the electromagnetic radiation from the interior from escaping. In effect, anything that passes the event horizon is unable to get away. Cygnus X-1 is spinning at a rate close to its maximum rate and the event horizon is spinning more than times per second, which is almost half the speed of light.

The physicists Stephen Hawking and Kip Thorne had a friendly wager about Cygnus X-1 in , with Hawking betting that the object was not a black hole. In , he conceded the bet after additional observational data had strengthened the theory that there really was a black hole in the system.

Cygnus X-1 and the supergiant star do not eclipse; Cygnus X-1 never goes behind the star. The mass of the black hole is estimated to be around Each rocket contained a directed Geiger counter, so that as the rocket rotated at the peak of its trajectory to measure the direction of x-ray sources. The project discovered eight x-ray sources, including a particularly bright one in the constellation Cygnus.

It became known as Cygnus X The x-rays were quite bright and came from a region almost starlike in size. This suggested that it could be a then hypothetical stellar-mass black hole.