The picture displays the accretion of the M87 black hole and the powerful jet it expelled. (PHOTO: SHAO)

By Staff Reporters

An international research team led by the Shanghai Astronomical Observatory (SHAO) of the Chinese Academy of Sciences has recently generated a picture that displays the accretion of the M87 black hole and the powerful jet it expelled, the first of its kind in the world. The result was published online in the journal Nature on April 26.

Many astronomers have successfully captured images of the M87 black hole's bright and 5,000 light-year-long jet before. However, for the first time, they have revealed a link between the black hole's accretion and the jet.

The very-long-baseline interferometry (VLBI) observations of M87 with the Global Millimetre VLBI Array (GMVA) were conducted from April 14 to 15, 2018, complemented by the phased Atacama Large Millimeter/submillimeter Array (ALMA) and the Greenland Telescope (GLT). The aperture of the telescope is equivalent to the diameter of the Earth. 

The first-ever photo of the M87 black hole was captured using a wavelength of 1.5 mm by the Event Horizon Telescope. However, for the most recent image, scientists opted for a wavelength of 3.5 mm.

Using a wavelength of 3.5mm for the recently released picture allows for a larger telescope array and observes a brighter jet of the blackhole, whereas the environment around the black hole was barely observable at a wavelength of 1.5 mm, said Lu Rusen, lead author of the research paper from SHAO.

According to Lu, involving ALMA and GLT in the telescope array has greatly enhanced its resolution and sensitivity, making it possible to produce an image of the ring-like structure of the M87 black hole at a wavelength of 3.5 mm.

In the future, scientists intend to take color images of the black hole or even record a video to further observe and research on it.