MOSCOW, December 20. /TASS/. Russian cosmonauts Alexey Ovchinin and Ivan Vagner (TASS correspondent aboard the ISS) closed the exit hatch of the Poisk module of the International Space Station, completing their spacewalk.

The extravehicular activity began at 6:36 p.m. Moscow time on Thursday. The cosmonauts were expected to spend six hours and 43 minutes in space, but their mission lasted 7 hours 17 minutes instead.

Their primary goal was to install and connect the SPIN-X1-MVN X-ray spectrometer on the Zvezda Service Module. The instrument will be able to monitor 84% of the celestial sphere and help scientists determine the number of supermassive black holes in the Universe.

Besides, Ovechkin and Vagner also dismantled research equipment from the Poisk module. Ovchinin then positioned himself in the ERA's portable manipulator arm workstation and flung the dismantled items away from the ISS. The garbage will soon burn up in the Earth's atmosphere.

This EVA was the first in Vagner career. He was wearing Orlan-ISS spacesuit No. 4 with blue stripes. Alexey Ovchinin, who was wearing Orlan-ISS spacesuit No. 5 with red stripes, was in outer space for a second time (for the first time during the current 72nd long expedition to the orbital outpost).

About the spectrometer

The spectrometer for the experiment All Sky Monitor was delivered to the station on the cargo spacecraft Progress MS-28 in August. In September, the Deputy Director of the Space Research Institute (SRI) under the Russian Academy of Sciences, associate member of the Russian Academy of Sciences Alexander Lutovinov told TASS that the device would go operational immediately after installation and perform 15 sky surveys in three years.

Lutovinov noted that the instrument would help scientists determine the number of supermassive black holes in the Universe and their contribution to its history by measuring the cosmic X-ray background - radiation made up of a huge number of distant objects that are almost impossible to view individually.