By Peter W. Merlin, special to Aerotech News
Nov. 2, 2020, marked the 20th anniversary of continuous human presence aboard the International Space Station. Assembly of the orbiting laboratory began in 1998 but it was two years before the ISS started hosting crews on a permanent basis.
On Oct. 31 the American Institute of Aeronautics and Astronautics Los Angeles-Las Vegas section hosted a virtual celebration of the anniversary.
The $100 billion space station was built by a consortium of 15 nations working under five international space agencies: NASA, the Russian State Corporation for Space Activities (Roscosmos), the European Space Agency (ESA), the Japan Aerospace Exploration Agency (JAXA), and the Canadian Space Agency (CSA). The American portion of the ISS was designated a National Laboratory in 2005, which allows its facilities to be used by non-NASA researchers.
Humans have lived and worked continuously aboard the ISS to test new technologies, conduct scientific research, and develop skills needed for long-duration space missions beyond Earth orbit.
To date, more than 240 people from 19 countries have visited the unique microgravity laboratory that has hosted more than 3,000 research investigations and educational programs from people around the world. Over the past two decades, multi-national ISS crews achieved many historic firsts including the first human to spend a year in space, the first all-female spacewalk, and the first commercial spacecraft to transport astronauts to the station.
The first permanent crew, designated Expedition 1, arrived at the ISS on Nov. 2, 2000. NASA mission commander William Shepherd, along with Russian cosmonauts Yuri Gidzenko and Sergei Krikalev, remained aboard for 136 days. During their stay, they activated various station systems, hosted three visiting Space Shuttle crews, and unpacked equipment delivered by two un-crewed Russian Progress resupply vehicles. Successive expeditions oversaw the addition of docking and laboratory modules and solar power systems that increased the station’s capabilities. Building the station in orbit required 41 assembly flights spread over 13 years. When complete the ISS weighed in at a mass of nearly 450 metric tons.
The ISS 20th anniversary was celebrated in orbit by the Expedition 64 crew, who began their six-month tour of duty on Oct. 21. Station commander Sergey Ryzhikov and flight engineers Kathleen Rubins and Sergey Kud-Sverchkov will be joined in November by Michael Hopkins, Victor Glover, and Shannon Walker of NASA, and Soichi Noguchi of JAXA; and four months later by Roscosmos cosmonauts Oleg Novitsy, Pyotr Dubrov, and Andrei Borisenko. The Expedition 64 mission is scheduled to end April 18, 2021.
The modular station was designed to accommodate three to nine persons at a time with crewmembers rotating on and off the ISS in weeks or months according to mission needs. A crew of six is capable of performing more than 50,000 hours of work in a single year of operations. The station commander is responsible for ensuring the day-to-day safety of the station and crew, and the efficiency and efficacy of onboard operations. This is a rotating position; members of any participating space agency are eligible to command the ISS. In October 2018, German astronaut Alexander Gerst ushered in the first twelve-month calendar year without a U.S. commander. During that period, ESA and Roscosmos shared command duties.
Throughout the station’s service life Russian Soyuz spacecraft, launched from Baikonur Cosmodrome in Kazakhstan, have been the primary workhorse for delivering crews and returning them to Earth. Prior to its retirement in 2011 the Space Shuttle also performed this function. Since that time the cost of flying an astronaut aboard a Soyuz has risen from $20 million to $80 million. As an alternative, NASA has begun contracting with SpaceX and Boeing for commercial spacelift services. In May 2020 two astronauts traveled to the ISS by way of a SpaceX Crew Dragon vehicle, and Boeing is set to debut the company’s CST-100 Starliner in 2021. Once in regular operation, these craft will hopefully reduce transportation costs by as much as 50 percent.
Additionally, un-crewed Dragon and Starliner variants will deliver supplies to the station.
Based in low Earth orbit the ISS provides a unique environment for conducting research requiring microgravity conditions or observations from 250 miles above the planet’s surface. Such experiments include advances in materials and manufacturing technologies, physics, chemistry, pharmaceutical development, weather modeling and prediction, air and water purification, and robotics. Research on board the station will enable future exploration on the moon and beyond Earth orbit. The ISS is an ideal platform to study life-support systems, test new spacesuit designs, and evaluate the physical and psychological effects of long-duration space missions on crew health and performance.
NASA initiatives currently call for the ISS to be decommissioned in 2024 but the agency’s international partners are considering an extension until at least 2028. One avenue under discussion is transitioning the ISS from a government-owned facility to a commercial venture. NASA Administrator Jim Bridenstine has openly supported this vision, in which the private sector would eventually take over ISS operations with NASA as one of many potential customers.
“The ISS is an amazing tool, and of course where we are right now, we’re going to use it for the maximum extent possible for as many years as we have left with it,” said Bridenstine during a presentation at the ISS Research & Development conference in August. The aging station will inevitably one day reach the end of its service life. Until that time the ISS remains a platform for international collaboration on cutting-edge research to aid future space travel and improve life on Earth.