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MLM Nauka expands
the International Space Station

Successfully launched on a Proton rocket on July 21, 2021, the Nauka Multi-purpose Laboratory Module, MLM, docked to the International Space Station, ISS, eight days later, giving the outpost a plethora of new capabilities and resuming the assembly of the station's Russian Segment after a decade-long hiatus. In development for nearly a quarter of a century, the 20-ton Nauka became Russia's largest spacecraft to enter orbit since the launch of the Zvezda Service Module to the ISS in 2000.

Previous chapter: MIM1 Rassvet module


The MLM Nauka module at a glance:

Spacecraft designation
MLM Nauka, 77KML No. 17901, ISS mission 6R
Launch vehicle
Proton-M, 8K82KM
Payload fairing
Payload adapter
Spacecraft prime developer
RKK Energia, Korolev, Russia
Spacecraft liftoff mass
20.257 tons
Mass in orbit at ISS (with radiator, airlock and other add-ons)
24.200 tons
13.1 meters
Solar panels span
23.9 meters
Pressurized volume
70 cubic meters
Available volume for cargo storage
4.9 cubic meters
Available volume for scientific payloads
6 cubic meters
Available power supply for scientific payloads
up to 2.5 kilowatts
Launch site
Official life span
10 years
Launch date
2021 July 21 (planned)

insider content

TKS: Where Nauka came from?

The MLM Nauka module is a direct descendant of the heavy TKS transport spacecraft conceived in the mid-1960s at OKB-52 design bureau lead by Vladimir Chelomei for the Almaz military space station project. The TKS was originally intended to carry crews and cargo to the Almaz but eventually its FGB component was re-purposed as a space station expansion vehicle. The MLM Nauka is the 12th and last member of this legendary spacecraft family to fly.


From FGB-2 to MLM: Origin of the Nauka project (1998-2011)

The MLM multi-purpose module (a.k.a. FGB-2 or 77KML No. 17901) originated as a backup copy to the first element of the International Space Station -- the Zarya control module, which was launched in November 1998.


2012: Development of the MLM

During 2012, the assembly of the MLM module was finally completed and in December it was shipped from GKNPTs Khrunichev rocket plant, RKZ, in Moscow to RKK Energia in Korolev for final tests before its planned trip to the Cosmodrome Baikonur for tests.


2013: MLM is hit with a contamination disaster

When the MLM/Nauka module was believed to be less than a year away from launch, engineers testing its systems made a startling discovery. The spacecraft's critical propulsion system turned out to be heavily contaminated with metallic dust. It was spread around the maze of pipelines, valves and combustion chambers during the "upgrades" of the spacecraft in the previous years.


2014: Russia considers scrapping troubled Nauka module

Faced with serious problems in preparing for launch their next big piece of the International Space Station, Russian engineers pondered leaving the ill-fated MLM/Nauka module behind and proceeding with the assembly of the Russian segment without this crucial element. The proposed architecture sans Nauka was found to be feasible but it would come at a high price.

2016 2015: Roskosmos re-commits to Nauka

After months of uncertainty, Roskosmos decided to jump-start the work on the MLM Nauka module in the hope of launching it within a couple of years. However many critical components of the module had to be manufactured from scratch or replaced with their equivalents if the originals were no longer available.

2015 2016: Work on MLM module stalls again

In June 2016, RKK Energia issued a press-release saying that the company completed the manufacturing and testing of equipment for the interior of the module. At the same time, the head of the company was quoted as saying that the development of documentation and the installation of large pieces of hardware on the exterior of the spacecraft had entered the final stage. However, as of middle of September, all the work on the assembly of the MLM module had stalled again.


2017: Engineers begin tackling problems with MLM

At the beginning of 2017 it seemed that MLM could fly at the end of that year or in the first half of the next, finally resuming the assembly of the Russian segment of the ISS. However in March another nasty surprise hit the ill-fated spacecraft...


2018: MLM Nauka module postponed again

By the end of January 2018, sources at GKNPTs Khrunichev, the manufacturer of the MLM Nauka module, said that continuing repairs of the spacecraft would likely delay its shipment to the Baikonur launch site until the end of July 2018. As of October 2017, the module was expected to be rolled out on March 15, 2018.

2019: MLM Nauka inches toward launch (INSIDER CONTENT)

By 2019, all the efforts to repair original propellant tanks for the MLM-U Nauka module bound to the International Space Station, ISS, reached a dead end and Roskosmos had to make a final decision about its launch, before even more critical systems, such as engines, would run out of warranty as well.

2020: Nauka slips into 2021 (INSIDER CONTENT)

On January 1, 2020, a Twitter account, which is attributed to Roskosmos head Dmitry Rogozin, posted an announcement stating that the MLM Nauka module will be shipped to Baikonur in March. That was at least a month-long delay from the delivery date promised by Rogozin around three months earlier. In reality, the module reached Baikonur on August 19. By that time, its launch was planned in April 2021.

2021: Nauka races toward finish (INSIDER CONTENT)

The pre-launch processing of the MLM Nauka module in Baikonur entered the final stage, with the liftoff of the 20-ton spacecraft to the Russian Segment of the International Space Station, ISS, scheduled for July 15.

Nauka's design and organizational structure (INSIDER CONTENT)

The 20-ton MLM-U Nauka module will become the sixth Russian-built long-term component of the International Space Station, ISS, and the third element of the outpost relying on the Proton rocket for launch. Nauka was designed to provide a new scientific potential for the Russian Segment, but also expand its technical capabilies and, possibly, even become the core of a future new station.


Structural design of the MLM's hull (INSIDER CONTENT)

The main body of the MLM Nauka module consists of four major structural components. This section describes their general architecture and operational warranty.


Science aboard Nauka (INSIDER CONTENT)

As its name suggests, the primary purpose of the MLM Nauka (science) module was to provide the Russian Segment of the International Space Station, ISS, with a world-class multi-purpose laboratory in orbit. The spacecraft was designed to provide room and facilities for experiments focused on material science and biotechnology. continuing the work conducted aboard the Kristall module of the Mir Space Station.

ShK Nauka introduces sophisticated science airlock (INSIDER CONTENT)

One of the key features of Russia's latest addition to the ISS, is a special airlock designed to take scientific experiments and other equipment from the pressurized interior of the station to the vacuum of space. In combination with Nauka's robotic arm, the science airlock allows quick and safe movement of hardware between interior and exterior of the Russian Segment.


Service systems aboard Nauka (INSIDER CONTENT)

Along with its scientific capabilities, the MLM Nauka module was designed to provide a number of critical service systems to the Russian Segment of the International Space Station. This equipment aboard Nuaka would also be critical if the Russian Segment was ever to operate as an independent outpost in the Earth's orbit after the retirement of the other ISS components.


Life-Support Systems (INSIDER CONTENT)

The MLM Nauka module was equipped with three-component life-support system. It was designed to manage the gas content in the module's atmosphere, provide hygiene functions for the crew and have fire-suppression capabilities.


Thermal-Control System (INSIDER CONTENT)

One of the critical support mechanisms aboard the MLM Nauka module will be a powerful thermal control system, SOTR. It will manage the temperature inside the spacecraft under extreme conditions in Earth's orbit, by rejecting excessive heat back into space as needed.


Nauka gets a new radiator (INSIDER CONTENT)

In addition to its built-in thermal control system, the Nauka module was to be outfitted with a large add-on radiator array, which was waiting for its host spacecraft's arrival to the station for more than a decade in folded position on the Rassvet module of the Russian Segment.


Power-Supply System (INSIDER CONTENT)

A pair of solar arrays, giving the MLM Nauka module its characteristic look, is only a part of a three-component complex, KES, designed to provide electric power to the spacecraft during its trip to the International Space Station, ISS. Comprised of many time-sensitive elements, the KES system had to go through many ups and downs on the road to the launch pad.


Nauka's Radio System (INSIDER CONTENT)

The Nauka module is equipped with a five-component radio system playing several important roles in its mission, especially during the planned eight-day solo flight from the initial orbit to the International Space Station, ISS. Like many other spacecraft originated in the USSR, Nauka relied on a Ukrainian-built command-receiving radio equipment to navigate to its destination.


Nauka to feature three different docking ports (INSIDER CONTENT)

The MLM module has three different docking mechanisms – one at the front and two on the opposite end of the spacecraft. The front docking port is designed for the attachment of Nauka to the nadir (Earth-facing) port of the Zvezda Service module, while one downward-facing port will be used to further expand the station and the third port, facing along the direction of the flight, will be used for the permanent attachment of a small airlock.


Nauka carries docking port - transformer (INSIDER CONTENT)

On its front section, the MLM module was equipped with a unique transformable docking mechanism designed to give the spacecraft the potential capability to serve as the cornerstone of the new Russian space station after the retirement of the ISS.


Unique docking port accommodates science airlock (INSIDER CONTENT)

The docking mechanism connecting the ShK airlock to Nauka and the associated control avionics unit BUBK is known as SSA-M (from the Russian Sistema Stykovki Aktivnaya - Modifitsirovannaya).


Tank system for the MLM module

In the spring of 2017, Russian engineers approved a new plan to cleanse the propellant tanks of the MLM module of severe metallic dust contamination. It required a delicate surgery-like dissection of the tanks to cleanse them of dangerous contaminants, while avoiding damage to their irreplaceable parts.

propulsion Nauka's propulsion system (INSIDER CONTENT)

One of the most critical features of the Soviet and Russian space station modules based on the TKS spacecraft was its ability to perform rendezvous in orbit and maneuver other vehicles docked to it. The Nauka module is no exception, but its engines and a maze of associated propellant lines required years-long overhaul before its flight.


Upgrading MLM propulsion system (INSIDER CONTENT)

In the first half of 2020, Russian specialists worked on upgrading the propulsion system of the MLM Nauka module to ensure that the spacecraft could make it to the International Space Station, ISS, with its potentially compromised propellant tanks.


Nauka's Flight-Control System (INSIDER CONTENT)

The MLM module was equipped with a multi-faceted flight control system designed to support its autonomous flight to the ISS and control onboard equipment as part of the International Space Station and, possibly, a future Russian station.


Cargo aboard MLM Nauka (INSIDER CONTENT)

The launch Nauka module gave Russian engineers a rare opportunity to deliver particularly bulky cargo to the ISS, taking advantage of the module's 70-cubic-meter interior.


History of the European Robotic Arm, ERA (INSIDER CONTENT)

The European Robotic Arm, ERA, will be one of the most significant components of Nauka, when it joins the ISS. Attached to the exterior, it will give the Russian Segment of the outpost the capability to take scientific experiments and other payloads from the pressurized volume of the station and deploy them on its exterior under remote control.


Design of the European Robotic Arm, ERA (INSIDER CONTENT)

The 630-kilogram European Robotic Arm is a seven-segment manipulator with a total reach of 9.7 meters and capable of moving objects with a mass of up to eight tons in weightlessness. For comparison, the Soyuz and Progress spacecraft have a mass of around seven tons.


Tools to activate the European Robotic Arm (INSIDER CONTENT)

The European Robotic Arm, ERA, came with a little known set of tools which were first used during the VKD-53 spacewalk to activate the device. Delivered with cargo ships, these instruments continue a long tradition of manual hardware designed specifically for use outside spacecraft.


Set of accessories complements the European Robotic Arm (INSIDER CONTENT)

In addition to a toolkit of manual instruments, ERA also came with a range of equipment and spares in orbit and on the ground to support various aspects of its operation.


NEW, Dec. 14: Operations of the European Robotic Arm (INSIDER CONTENT)

Most of ERA’s actions were expected to take place during extra-vehicular activities, EVAs. For example, the transfer of all heavy items with the arm was to be performed in the presence of spacewalkers. The need for close interaction between the cosmonauts outside the station and the operator of the arm, as well as safety requirements associated with spacewalks, defined a number of criteria for their joint activities.


NEW, April 18: Contingencies during the operation of the European Robotic Arm, ERA (INSIDER CONTENT)

The critical role of the European Robotic Arm, ERA, during spacewalks and its interaction with spacewalking cosmonauts required engineers on the ground to develop action algorithms in case anything goes wrong at various stages in the process of transferring cargo with the remotely controlled manipulator.


Preparing Nauka at launch site (INSIDER CONTENT)

After two decades in assembly, Russia's MLM Nauka module finally came within months from the trip to its launch site at Baikonur Cosmodrome in Kazakhstan in 2020. However, it will take at least eight or nine months of careful tests and critical activities to bring the 20-ton vehicle to the launch pad. Here is the step-by-step description of what will have to be done.


Processing facility for Nauka module at Site 254 (INSIDER CONTENT)

The delivery of the Nauka module to Baikonur Cosmodrome in August 2020 marked the beginning of the launch campaign for the 20-ton spacecraft. It was the first time in two decades that the Russian personnel in Kazakhstan had to work with the a space station module of this size and complexity. To complete the task, a dedicated preparation facility was deployed inside the former Buran processing building at Site 254.


Integrating Nauka with the ISS

To support the addition of the MLM Nauka module to the ISS, the Russian cosmonauts aboard the outpost had to perform many chores preceding the docking of the 20-ton spacecraft. And once the module was in place, the ISS crew was expected to conduct up to 11 spacewalks to fully plug all the systems of the new room into their home in orbit. The total in-orbit time required to integrate Nauka was expected to reach 2,000 work hours!


Preparing ISS for Nauka's liftoff (INSIDER CONTENT)

The work to configure the International Space Station for the addition of the MLM Nauka module began years before it had a chance to fly, but the most critical activities aboard the Russian Segment of the outpost preparing for the new arrival are expected to take place within a month before the start of the mission.


VKD-48 spacewalk prepares Pirs' departure from ISS (INSIDER CONTENT)

On June 2, 2021, two Russian members of Expedition 65 aboard the ISS, ventured on the exterior of the outpost's Russian Segment in the first of 11 spacewalks laying groundwork for the MLM Nauka module. The spacewalk, designated VKD-48, had the main goal of preparing the separation of the Pirs Docking Compartment, SO1, for the departure from the ISS and clearing the docking port for Nauka.


Nauka's launch scenario (INSIDER CONTENT)

The launch of the MLM Nauka module was scheduled from Pad 39 at Site 200 in Baikonur Cosmodrome. It was to be the first launch of the three-stage Proton variant in 21 years aYesnd the first launch of the rocket configured to carry the TKS-derived spacecraft since 1998, when the Zarya FGB control module kicked off the assembly of the ISS.

Nauka's mission

Nauka lifts off (INSIDER CONTENT)

A Proton-M rocket, carrying 23-ton cargo section lifted off on July 21, 2021, from Baikonur Cosmodrome in Kazakhstan, sending the MLM Nauka module on an eight-day chase of the International Space Station, ISS.


Autonomous flight of the Nauka module (INSIDER CONTENT)

The Nauka's launch encountered only minor glitches, but mission control discovered serious problems with the spacecraft once it had entered an initial orbit.


Preparing Russian Segment for MLM docking after its launch (INSIDER CONTENT)

The second phase of activities aboard the station will have to be cramped into a nine-day period between the launch of the Nauka module and its docking with the outpost. It will culminate with the departure of the Pirs Docking Compartment from the station, concluding its two-decade tenure on the ISS, which poses technical risk of its own.


Nauka integration after ISS docking (INSIDER CONTENT)

The arrival of the Nauka module at the International Space Station, ISS, will mark the long-delayed completion of the first phase in the construction of the outpost's Russian Segment. However, Russian cosmonauts will be busy for many months after the docking of the 20-ton spacecraft to make it a fully functional part of their home in orbit.


VKD-49 spacewalk (INSIDER CONTENT)

Cosmonauts Oleg Novitsky and Petr Dubrov performed the first venture on the exterior of the newly arrived MLM-U Nauka module on Sept. 3, 2021, to connect it to power supply. However, due to lack of time, the crew did not complete the connection of the Ethernet cable, the installation of transfer railings and experimental containers on the exterior. All these tasks had to be deferred to other sorties.


VKD-50 spacewalk (INSIDER CONTENT)

The VKD-50 spacewalk, scheduled on Sept. 9, 2021, was originally focused on connecting rendezvous and TV data cables to the newly arrived Nauka module of the International Space Station. However after several tasks from the preceding sortie had to be deferred due to lack of time, the follow-on excursion on the exterior of the station became even more critical.


The European Robotic Arm comes alive aboard Nauka (INSIDER CONTENT)

The successful completion of the VKD-49 spacewalk aboard the ISS, on September 3, 2021, brought the power supply to the Nauka module necessary for the operation of its equipment associated with the European Robotic Arm, ERA.


ERA activities in 2022 (INSIDER CONTENT)

In early 2022, Russian and European specialists were finalizing a new plan to resume the stalled activation of the European Robotic Arm, ERA, that had arrived to the International Space Station, ISS, with the Nauka module in July 2021.


VKD-52 spacewalk prepares controls for Nauka's robotic arm (INSIDER CONTENT)

On April 18, 2022, Russian cosmonauts made their first outing on the exterior of the Russian Segment of the International Space Station, ISS, to activate the European Robotic Arm, ERA, stored on the newly arrived Nauka module.


Russian spacewalk animates European Robotic Arm (INSIDER CONTENT)

During the VKD-53 spacewalk on April 29, 2022, Russian cosmonauts assisted first movements of the European Robotic Arm, ERA, aboard Nauka. It was the sixth sortie in support of integrating Nauka and Prichal modules with the Russian ISS Segment.

ISS crew members perform add-on spacewalk (INSIDER CONTENT)

Once the European Robotic Arm, ERA, was put into its operational parking position after the VKD-53 spacewalk, the next step in readying the device was to prepare it for carrying a simulated cargo. However that milestone took considerably longer than originally planned to achieve and it required an extra spacewalk.


Spacewalk to outfit European Robotic Arm (INSIDER CONTENT)

After the successful completion of the add-on VKD-ESA spacewalk, the operations to activate ERA, got back to the original plan of carrying a simulated cargo. The work was assisted by a pair of spacewalking cosmonauts who were scheduled to work on the exterior of the Russian Segment for six and a half hours on Aug. 17, 2022, however their sortie was cut short due to a power-supply problem in one of the spacesuits.


Preparing RTOd for the move (INSIDER CONTENT)

In 2022, Roskosmos added an extra sortie into a series of spacewalks aimed to integrate newly arrived Nauka and Prichal module with the Russian Segment of the ISS. Scheduled for Nov. 17, 2022, it was designated VKD-55, according to the sequence of Russian spacewalks aboard the ISS and became the 10th spacewalk since 2021 to integrate the pair of new modules.


NEW, Jan. 27: New push to outfit Nauka (INSIDER CONTENT)

In early 2023, specialists responsible for the outfitting of the Nauka module re-arranged their plans after a major setback caused by the emergency situation aboard the Soyuz MS-22 spacecraft.


First job for European Robotic Arm (INSIDER CONTENT)

Soon after the activation of the European Robotic Arm, ERA, it will have to perform its first major task of outfitting the Nauka with an external radiator. The complex operation will be choreographed with the VKD-56 spacewalk by a pair of Russian cosmonauts.


Nauka to get science airlock (INSIDER CONTENT)

Perhaps the most critical step in making Nauka to live up to its name will be outfitting the module with a science airlock. The installation of the component on Nauka will be assisted by a pair of cosmonauts on the exterior of the Russian Segment during the VKD-57 spacewalk.


How cosmonauts deployed radiator aboard Nauka (INSIDER CONTENT)

During the VKD-58 spacewalk, Russian cosmonauts are scheduled to return to the task of outfitting the Nauka module with an extra radiator. This time, the previously installed heat-rejecting array will be deployed and get readied for operation.


Activating Nauka's airlock (INSIDER CONTENT)

During the VKD-60 spacewalk on Aug. 9, 2023, Russian cosmonauts will perform some of the final tasks in configuring the Nauka module for long-term operation as a part of the Russian ISS Segment.

All articles and illustrations inside this section by Anatoly Zak unless stated otherwise. All rights reserved

Last update: December 2, 2023