{"id":3257,"date":"2011-11-21T13:33:08","date_gmt":"2011-11-21T02:33:08","guid":{"rendered":"https:\/\/scienceillustrated.com.au\/blog\/?p=3257"},"modified":"2011-11-21T13:33:08","modified_gmt":"2011-11-21T02:33:08","slug":"black-hole%e2%80%99s-history-reconstructed-for-the-first-time","status":"publish","type":"post","link":"https:\/\/scienceillustrated.com.au\/blog\/science\/black-hole%e2%80%99s-history-reconstructed-for-the-first-time\/","title":{"rendered":"Black hole’s history reconstructed for the first time"},"content":{"rendered":"
\"\"<\/p>\n

The black hole takes material from the companion star. Credit: NASA\/CXC\/M.Weiss<\/p>\n<\/div>\n

Astronomers have produced a complete description of Cygnus X-1’s black hole.<\/strong><\/p>\n

Cygnus X-1 is a binary star system, consisting of a black hole and a companion star, which was discovered to be strongly emitting x-rays nearly 50 years ago. The mass concentration of the black hole is so dense that not even light can escape from it.<\/p>\n

Astronomers from the National Radio Astronomy Observatory<\/a> in the US have managed to reconstruct the black hole’s history, dating from its birth six million years ago. The team, led by Mark Reid of the Harvard-Smithsonian Center for Astrophysics<\/a>, used the National Science Foundation’s<\/a> Very Long Baseline Array<\/a> (VLBA) to measure the distances.<\/p>\n

This is the first time scientists have been able to reconstruct a black hole’s complete history. In the case of Cygnus X-1, previous attempts to measure the mass and spin of the black hole lacked precise distance measurements.<\/p>\n

“Because no other information can escape from a black hole, knowing its mass, spin, and electrical charge gives a complete description of it,” Reid said. “The charge of this black hole is nearly zero, so measuring its mass and spin make our description complete.”<\/p>\n

The VBLA allowed the team to take precise trigonometric measurements, allowing them to calculate a distance of 6070 light years. This measurement, combined with observations from the Chandra X-Ray Observatory, the Rossi X-Ray Timing Explorer, the Advanced Satellite for Cosmology and Astrophysics, and visible-light observations, allowed scientists to determine that the black hole is spinning over 800 times per second.<\/p>\n

The results also revealed that the black hole has a mass nearly 15 times that of our Sun, making it one of the most massive stellar black holes in the Milky Way galaxy.<\/p>\n

“This new information gives us strong clues about how the black hole was born, what it weighed and how fast it was spinning,” Reid said. “Getting a good measurement of the distance was crucial.”\u009d<\/p>\n

The VLBA observations, which were made during 2009 and 2010, also measured Cygnus X-1’s movement through the Milky Way. According to the scientists, the system’s movement is too slow for the black hole to have been produced by a supernova explosion.<\/p>\n

An explosion would have given the object a kick to a much higher speed. “There are suggestions that this black hole could have been formed without a supernova explosion, and our results support those suggestions,” Reid said.<\/p>\n

Source: National Radio Astronomy Observatory<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Astronomers have produced a complete description of Cygnus X-1’s black hole.<\/p>\n","protected":false},"author":13,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[62,38,8,27],"tags":[],"class_list":["post-3257","post","type-post","status-publish","format-standard","hentry","category-astrophysics","category-nasa","category-science","category-space"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/posts\/3257"}],"collection":[{"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/users\/13"}],"replies":[{"embeddable":true,"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/comments?post=3257"}],"version-history":[{"count":2,"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/posts\/3257\/revisions"}],"predecessor-version":[{"id":3261,"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/posts\/3257\/revisions\/3261"}],"wp:attachment":[{"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/media?parent=3257"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/categories?post=3257"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/scienceillustrated.com.au\/blog\/wp-json\/wp\/v2\/tags?post=3257"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}