The space agency is to begin modification work on the International Space Station this week, to enable it to receive two commercial space vehicles.

Relations between the United States and Russia have deteriorated drastically of late over the ongoing crisis in Ukraine, and could have potential ramifications for the ISS. The reconfiguration of the space station will be completed by the end of the year if all goes according to plan, and is the first significant overhaul since the station was completed in 2011, writes Irene Klotz for Discovery.com.

NASA To Modify ISS To Receive Commercial Vehicles

NASA to regain independence from Russia

In order to construct the station, parts were taken into space using the now-retired space shuttle. Since the iconic vehicle was retired from service, NASA has been paying Russia $70 million per person in order to get its astronauts up to the ISS. In order to end its reliance on Russia, the space agency has given contracts to Boeing and SpaceX to develop vehicles that can take astronauts to and from the station.

As well as securing the future of U.S. involvement in the ISS at a time of rocky relations with Russia, NASA will save money by paying only $58 million per person to the private contractors. To make this possible, certain adjustments must be made to the station’s docking ports to allow for the arrival of Boeing’s CST-100 and SpaceX’s Dragon capsules.

Lengthy process

Other necessary gear for the commercial capsules will be installed over the course of seven spacewalks, due to take place this year. This Friday, NASA’s station commander Barry “Butch” Wilmore and flight engineer Terry Virts will undertake the first of three spacewalks scheduled for the next few weeks.

Preparing the docking adapters is a complicated process which will require the delivery of new pieces of hardware from Earth, the aforementioned spacewalks and the use of a robotic arm controlled by NASA engineers on Earth.

“This is quite a bit of work,” space station program manager Mike Suffredini said. “Our plan has always been to have a docking capability in place and operational by the end of 2015 and we’re on track to do that.”

The new vehicles will be capable of carrying 4 astronauts at a time, which will enable the live-aboard crew to expand from 6 members to 7. The SpaceX Dragon V2 should be ready for its first test flight in late 2016, while Boeing plans to undertake a test flight of its CST-100 capsule in April 2017.