RF FCC to adjust ISS orbit for docking with spacecraft

An FCC official has told Itar-Tass, "In accordance with the programme for ballistic ensurance of the ISS flight, an ISS orbit adjusting maneuver is scheduled for December 22".

"The maneuver will be carried out with the use of eight berthing and orientation engines of the supply spacecraft Progress M-07M, which is docked with the assembly compartment of the service module Zvezda (star). The purpose of the operation is to shape optimum ballistic conditions prior to the arrival of the resupply spacecraft Progress M-09M and the space shuttle Discovery, the launches of which are slated for January 28 and February 3, 2011, respectively," the FCC official specified.

"According to the FCC ballistics service, the engines of the Progress spacecraft will be ignited at 19:28, Moscow time, and will operate for 1,270 seconds. As a result, the ISS will get an additional impulse of 2.4 metres per second. The average altitude of its orbit will rise by 4.2 kilometres and will be 352.9 km. Fuel for the maneuver will be used from the tanks of the functional cargo block Zarya (dawn)," the FCC official pointed out.

ISS orbit adjustment maneuvers are usually carried out to bring the ISS to a needed orbit to dock with a resupply spacecraft or a manned spaceship, as well as to evade space debris.

The ISS orbit altitude gets lower by 150-200 metres every day under the action of the Earth's gravitational pull and other factors.