The antenna is the size of the Earth began to photograph the black hole at the center of the milky Way
The participants of the project Event Horizon Telescope began observing the environment of the black hole at the center of the milky Way. To do this, they combined the eight radio telescopes in an interferometer with a resolution equivalent to the resolution of a radio telescope the size of the Earth. Monitoring will continue until 15 April, reports Space.com.
Black hole at the center of the milky Way, called Sagittarius a*, is removed from us at 26 thousand light years. Despite the fact that its radius is estimated at just 24 million kilometers (which is twice the orbit of mercury), its mass, according to the latest estimates, approximately 4 million solar. Despite the fact that this object is in our galaxy, his observation is not quite easy task. Given the size of Sagittarius A* and the distance to it, trying to see a black hole with a single telescope, equivalent to trying to see a rubber ball on the surface of the moon.
Scientists estimate that to achieve such a resolution required a telescope with an aperture of about 10 thousand kilometers for comparison, the Earth’s diameter is slightly less than 13 thousand kilometers.
However, to create such a huge system, using the method of radiointerferometry with superlong bases. In this case, several of the telescopes located on different continents are combined in the interferometer, which mimics a telescope with a size equal to the maximum distance between the devices.
The project Event Horizon Telescope will combine eight telescopes of the six points of the globe — Spain, Arizona, Hawaii, Mexico, Chile and Antarctica. Especially important is the role played by the accession of the ALMA Observatory: thanks to this sensitivity and the resolution of the EHT has increased considerably.
Due to the fact that ALMA poses the interferometer 66 of the receiving antennas, connected to the common system was not a trivial task. Researchers from mit have created a special software and equipment, including the maser on the hydrogen atoms and the fiber-optic system that allows you to transfer data at speeds of 8 gigabits per second for four recorders (Mark 6). After updating to 61 of the ALMA telescope will be able to work in sync with each other and with other project participants.
If the weather conditions in all parts of the world are good, astronomers will gather the necessary data for the five nights. The researchers hope to capture structure in the streams of gas around the black hole and to assess the size of its event horizon. According to scientists, this will allow to verify the General theory of relativity in extreme conditions. In addition, astronomers will conduct observations of the black hole in the nucleus of a nearby supergiant elliptical galaxy M87.
The data processing will take at least a year. Information is collected on hard drives and sent “manually” on the aircraft in the center of MIT Haystack, after which the researchers will integrate and analyze it. The publication of the first results of the observations is expected only in 2018.
However, EHT has the largest synthetic aperture among the systems of the radio telescopes. The international project “RadioAstron” includes a 10-m space radio telescope, which can be combined with other ground-based telescopes, creating an aperture with a size of several hundreds of thousands of kilometers. The achievements of the project “RadioAstron” you can read in our materials (1, 2, 3).