Expedition 74

International Space Station (ISS)

International Space Station

Expedition 74 began on December 9, 2025, at 01:41 UTC, with the undocking of Soyuz MS-27 from the International Space Station (ISS). The departing crew included Sergey Ryzhikov (RSA), Alexey Zubritsky (RSA), and Jonny Kim (NASA), concluding their mission and marking the end of Expedition 73.

2025-12-09

Artemis 2

Artemis Program

Orion

2026-03-06

Expedition 73

International Space Station

Expedition 73 began on April 19, 2025, at 21:57 UTC, with the undocking of the Soyuz MS-26 (72S) spacecraft from the International Space Station (ISS, “the station”). The departing crew included Aleksey Ovchinin (RSA), Ivan Vagner (RSA), and Don Pettit (NASA).

2025-12-09

2025-04-19

SANS_CM

envihab

Expedition 71

International Space Station

Expedition 71 began April 6, 2024, upon the departure of the Soyuz MS-24 (70S) from the International Space Station (“ISS,” “the station”).

Expedition 72

International Space Station

Expedition 72 began on September 23, 2024, with the undocking of the Soyuz MS-25 (71S) spacecraft from the International Space Station (ISS). The departing crew included Oleg Kononenko (RSA), Nicolai Chub (RSA), and Tracy Caldwell-Dyson (NASA).

Expedition 70

International Space Station

Expedition 70 began on September 27, 2023, with seven crewmembers on board the International Space Station (ISS, “the station”). Crewmembers transferring from Expedition 69 to Expedition 70 were Jasmin Moghbeli (NASA), Andreas Mogensen (Expedition 70 Commander, ESA), Satoshi Furukawa (JAXA), Konstantin Borisov (RSA), Oleg Kononenko (RSA), Nikolai Chub (RSA), and Loral O’Hara (NASA).

While operating and maintaining the ISS, the Expedition 70 crew continued performing the many research experiments in progress as well as initiating others. Research efforts included technological demonstrations as well as biology, Earth science, human science, and physical science investigations.

While three spacewalks were planned, only two were carried out. Chub and Kononenko completed their planned spacewalk on October 25. Moghbeli and O’Hara completed their spacewalk on November 1. The spacewalk, dubbed USOS EVA 89, lasted 6 hours and 42 minutes during which the pair replaced a bearing that will keep the solar arrays on the ISS rotating properly, performed other maintenance chores, and prepared for removal of an electronics box from a communications antenna.

The third private astronaut mission by Axiom Space launched to the station on January 18, docking on January 20. The Axiom-3 (AX-3) crew focused on scientific research, educational activities, and demonstrations. More than thirty experiments were conducted by the first all European commercial astronaut crew to visit the station. Expected to live and work with the Expedition 70 crew for 14 days, the Axiom-3 crew remained on board several more days due to weather conditions in the splashdown area. Axiom-3 undocked on February 7 and splashed down near Daytona Florida on February 9.

Preparation for the transition from Expedition 70 to 71 began March 3 when SpaceX Crew-8 launched on March 3. With the docking of the Crew Dragon and the opening of the hatch on March 5, Matthew Dominick (NASA), Michael Barratt (NASA), Jeanette Epps (NASA), and Alexander Grebenkin (RSA) joined the Expedition 70 crew.

Less than a week later, on March 10, Mogensen turned command of the ISS over to Kononenko. On March 11, SpaceX Crew-7 undocked and returned Moghbeli, Mogensen, Furukawa, and Borisov to Earth on March 12.

The last crew vehicle to arrive at the station during Expedition 70, Soyuz MS-25 (71S), launched on March 23 and docked to the station on March 25. On board were crewmember Tracy Caldwell-Dyson (NASA) and two visiting crewmembers, Oleg Novitskiy (RSA) and Marina Vasilevskaya (Belarus Space Agency). Caldwell-Dyson will remain aboard for a nominal six-month mission.

Novitskiy and Vasilevskaya joined the ISS crew for a twelve day visit before returning home. O’Hara, having completed 204 days in space on her first spaceflight, joined them in their Soyuz MS-24 (70S) vehicle for their return flight home. The Soyuz MS-24 (70S) undocked on April 5 and landed safely on a Kazakhstan steppe April 6.

With crew rotation complete and the departure of the Soyuz MS-24, Expedition 70 ended on April 6, 2024.

STS-69

BRIC-06,DSO69,NIH.C4

Shuttle Program

Endeavour

11 days

STS-69 was the 9th flight of the Space Shuttle Endeavour and the 71st flight of the Space Shuttle System. The launch was postponed two times. The first postponement was needed to correct a minor fault with the solid rocket booster O-rings, and the second was due to an anomalous condition in one of the fuel cells. The crew was nicknamed the "Dog Crew" and awoke to Elvis Presley's song, "You Ain't Nothing But A Hound Dog", to begin their first full day in space. The orbiter crew included Commander David M. Walker, Pilot Kenneth D. Cockrell, Payload Commander James S. Voss, and Mission Specialists James H. Newman and Michael L. Gernhardt.

The primary objective of STS-69 was the deployment and retrieval of the Wake Shield Facility (WSF). The WSF is a 12 foot diameter, saucer shaped, stainless steel satellite that flew free of the Shuttle for several days. While the WSF flew free of the Shuttle, it generated an "ultra-vacuum" environment in space. Inside the vacuum, thin semiconductor films for next-generation advanced electronics were developed. The commercial applications for these new semiconductors include digital cellular telephones, high-speed transistors and processors, fiber optics, opto-electronics and high definition television (HDTV).

A second objective was the deployment and retrieval of the Spartan 201 astronomy satellite. The Spartan 201 mission was a scientific research effort aimed at investigating the interactions between the Sun and its outflowing wind of charged particles. Spartan's goal was to study the outer atmosphere of the Sun and its transition into the solar wind that constantly flows past the Earth. This flight was intended to coincide with the passage of the Ulysses spacecraft over the sun's northern polar region. Ulysses was a cooperative deep space mission between the European Space Agency (ESA) and NASA, which was launched from the Space Shuttle in 1990 (STS-41) with the goal of studying the Sun at high heliographic latitudes.

Life sciences payloads aboard STS-69 included the National Institutes of Health Cells (NIH-C4) and the Biological Research in Canister (BRIC-6). NIH-C4 was the fourth in a series of eight collaborative missions between NASA and the National Institutes of Health. The two experiments in NIH.C4 were designed to study the effects of microgravity on bone cells. One experiment studied whether space flight caused changes in osteoblasts consistent with a reduction in bone formation and an increase in bone resorption. The second experiment was designed to study the effect of space flight on bone cell formation and loss. Two established bone-cell lines, one rat and one human, were used in each of the experiments. The cells for each experiment were loaded into cartridges and placed into the Space Tissue Loss-A (STL-A) module, which fits inside a Shuttle middeck locker. The automated STL-A collected and stored cell fractions during flight for analysis upon return to Earth.

STS-69 was the sixth flight of a BRIC payload. BRIC payloads consist of passive experiments contained within a metal canister placed in a middeck locker with foam padding used to dampen vibrations. The BRIC-06 payload was specifically designed to study the gravity-sensing mechanism within mammalian cells. BRIC experiment specimens were exposed to the temperatures, carbon dioxide, oxygen, atmospheric pressure and humidity conditions of the middeck.

Other life sciences experiments performed during the STS-69 mission were those classified as Detailed Supplementary Objectives (DSOs). A DSO is a NASA-sponsored investigation performed by Space Shuttle crewmembers, who serve as the test subjects. These studies are designed to require minimal crew time, power and stowage. Biomedical DSOs focus on operational concerns, including space motion sickness, cardiovascular deconditioning, muscle loss, changes in coordination and balance strategies, radiation exposure, pharmacokinetics and changes in the body's biochemistry.

Additional payloads flying aboard Endeavour were the combined Capillary Pumped Loop-2/Gas Bridge Assembly, the International Extreme Ultraviolet Hitchhiker and the Electrolysis Performance Improvement Concept Study. Several Get Away Special (GAS) payloads also flew on STS-69. Get Away Special (GAS) payloads are payloads in canisters mounted to the side wall of the Shuttle payload bay or on a cross bay truss structure. These payloads are operated by the Shuttle's crew and provide their own battery power. These experiments investigated areas such as the interaction of spacecraft attitude and orbit control systems with spacecraft structures, fluid-filled beams as structural dampers in space and the effects of smoldering combustion in a long-term microgravity environment.

On the tenth flight day, Mission Specialists Jim Newman and Mike Gernhardt performed a 6-hour spacewalk to evaluate and verify specific assembly and maintenance techniques for the International Space Station. In addition, the spacewalk evaluated spacesuit design modifications that will protect astronauts from the extremely cold environment of space.

STS-69 landed on September 18, 1995, at Kennedy Space Center in Florida.

STS-63

BRIC-03,CHROMEX-06,DSO63,Immune.2,NIH.C3,STS-63

Shuttle Program

Discovery

8 days

The Space Shuttle Discovery (STS-63), which launched on February 3, 1995, was the first mission to be flown with a female pilot, Astronaut Eileen M. Collins. The other orbiter crewmembers were Commander James D. Wetherbee, and Mission Specialists C. Michael Foale, Janice E. Voss, Bernard A. Harris, Jr., and Vladimar G. Titov.

The primary objective of the STS-63 mission was to perform a rendezvous and flyby of the Russian space station Mir. The objective of this flyby was to verify flight techniques, communications and navigation aid sensor interfaces and engineering analyses to prepare for the STS-71 mission, the first Shuttle mission planned to dock with the Mir station.

Additional objectives for this flight were to perform the operations necessary to fulfill the requirements of experiments located in Spacehab-3 and to deploy and retrieve the Spartan-204 payload. Spartan-204, the Shuttle Pointed Autonomous Research Tool for Astronomy, was a free-flying retrievable platform designed to obtain data from diffuse sources of light in the far ultraviolet region of the spectrum. Two crewmembers, C. Michael Foale and Bernard A. Harris, also performed a five-hour spacewalk to evaluate how well they could manipulate this 3,000-pound satellite in weightlessness and test new thermal devices designed to warm their spacesuits. This EVA made Harris the first African-American to walk in space.

Life sciences payloads on this mission included the Immune Response Experiment (Immune.2), National Institutes of Health Cells Experiment (NIH-C3), Biological Research in a Canister (BRIC-3) and Chromosome and Plant Cell Division Experiment (CHROMEX-06). IMMUNE.02 was a collaborative project between NASA and Chiron Corporation that tested the ability of polyethylene glycol interleukin-2 (PEG IL-2) to prevent the short-term suppression of the immune system observed during microgravity exposure. This work has possible applications for treating disease- and age-related immunosuppression on Earth.

The NIH.C3 life sciences payload was a continuation of the studies initiated on NIH.C1, (STS-59) designed to examine the possible effects of space flight and microgravity on a number of aspects of osteoblast cell growth and gene expression. In particular, the studies examined the hypothesis that unloading bone cells in space flight will result in altered bone matrix production and mineral formation.

STS-63 was the third flight of the Biological Research in a Canister (BRIC-03) small payloads flight project. The payload consisted of passive experiments contained within a metal canister placed in a middeck locker with foam padding for vibration dampening. BRIC-03 experiments were specifically designed to study the development and differentiation of soybeans, as well as the effects of microgravity on the plant's carbohydrate metabolism, which provides plants the energy they need to grow. BRIC experiment specimens were exposed to the temperatures, carbon dioxide, oxygen, atmospheric pressure and humidity conditions of the middeck; little to no crew interaction with the payload was required.

STS-63 was the sixth flight of the Chromosome and Plant Cell Division Experiment (CHROMEX-06). CHROMEX payloads fly in the middeck of the Shuttle. The payload consisted of experiments using the Plant Growth Unit (PGU), which allowed scientists to grow whole plants in orbit. The plants were allowed to grow for the length of the mission and were analyzed postflight to determine the effects of microgravity and space flight on their cell wall structure; little to no crew interaction with the payload was required.

Other life sciences experiments performed during the STS-63 mission were those classified as Detailed Supplementary Objectives (DSOs). A DSO is a NASA-sponsored investigation performed by Space Shuttle crewmembers, who serve as the test subjects. These studies are designed to require minimal crew time, power and stowage. Biomedical DSOs focus on operational concerns, including space motion sickness, cardiovascular deconditioning, muscle loss, changes in coordination and balance strategies, radiation exposure, pharmacokinetics and changes in the body's biochemistry.

Additional payloads flying aboard STS-63 included the Cryo Systems Experiment, Shuttle Glow experiment, Cosmic Radiation Effects and Activation Monitor, Orbital Debris Radar Calibration Spheres, the Solid Surface Combustion Experiment, the Air Force Maui Optical Site (AMOS) Calibration Test and the Midcourse Space Experiment.

Space Shuttle Discovery landed at Kennedy Space Center on Saturday, February 11, 1995, after a successful 8-day mission.

STS-58

BSP58,DSO58,SLS-2

Shuttle Program

Columbia

14 days

The Spacelab Life Sciences 2 (SLS-2) mission was the second in a series of flights dedicated to the study of life sciences in space utilizing the orbiting scientific laboratory, Spacelab. The first mission, SLS-1, flew in June 1991 and provided the first opportunity since Skylab to comprehensively study changes in human physiology upon exposure to microgravity. The SLS-2 mission, which was a continuation and extension of the SLS-1 studies, consisted of 14 experiments that investigated the cardiovascular, cardiopulmonary, endocrine, renal, hematological, muscular, skeletal and vestibular systems in rodents and humans. The SLS-2 crew included Commander John E. Blaha, Pilot Richard A. Searfoss, and Mission Specialists M. Rhea Seddon, William S. McArthur, Jr., David A. Wolf, Shannon W. Lucid, and Martin Fettman.

Four investigations fell in the discipline of regulatory physiology, studying the renal/endocrine and the hematological systems. The renal/endocrine system consists of the kidneys and endocrine glands that control hormones regulating blood volume, blood pressure and essential electrolytes (dissolved salt and minerals, such as sodium, potassium, calcium and phosphate) in the blood. The regulatory function of the renal/endocrine system exhibits both acute (hours to days) and adaptive (days to weeks) responses to microgravity in conjunction with the cardiovascular response to the headward fluid shift. Renal/Endocrine and hematology investigations studied two components of blood: plasma and red blood cells. By analyzing plasma, the fluid portion of the blood, investigators can identify the types of nutrients circulating throughout the body to determine if an astronaut is well-nourished and hydrated. Researchers also studied the noted decrease in red blood cell production that is regarded as a potential space flight problem that could acquire increased significance with inflight illness or injury, particularly on long-duration missions.

Scientists hypothesize that there are many ways weightlessness affects the cardiovascular and cardiopulmonary system. Results from SLS-1 showed an increase in the heart rate, heart size and cardiac output, presumably in response to the initial increase in central blood volume caused by the fluid shift. Three SLS-2 investigations assessed the function of this system by monitoring cardiac output (volume of blood pumped per minute), heart rate, arterial and venous blood pressure, blood volume and the amount and distribution of blood and gases in the lungs.

In microgravity, the musculoskeletal system is not used as intensively as it is on Earth. The absence of gravitational force results in changes to load-bearing tissues, causing a reduction of bone and muscle. Astronauts float instead of using their legs for locomotion. In addition, the metabolic state of the musculoskeletal system may be altered by changes in dietary intake and exercise levels and also space motion sickness. In turn, losses from gravity-bearing tissues contribute to the reduced fitness of astronauts when they return to Earth. The general objective of the five musculoskeletal investigations was to study the changes in protein and calcium metabolism and bone homeostasis that occur in microgravity.

Neurovestibular changes related to equilibrium and body orientation affect the early inflight performance of astronauts probably more than any of the other physiological changes. The awareness of body orientation on Earth is attributed, in part, to the detection of gravity by the otolith organs in the inner ear. Gravity sensors in the joints and touch sensors in the skin also are involved, and the eyes contribute by sensing the body's relationship to other objects. In weightlessness, information sent to the brain from the inner ear and other sense organs no longer corresponds to the cues experienced in Earth’s environment. These conflicts can cause disorientation or space motion sickness. Although adaptation occurs within a few days and crewmembers are usually able to operate efficiently, investigators are working to better understand and counter these negative effects. The goals of the two neuroscience investigations of SLS-2 were to document the changes that occur in the neurovestibular system, to investigate the mechanisms involved in these changes and to identify countermeasures to alleviate the effects of space motion sickness.

Detailed Supplementary Objectives (DSOs) were also performed on this mission. A DSO is a NASA-sponsored investigation that is performed by Space Shuttle crewmembers, who serve as the test subjects. These studies are designed to require minimal crew time, power and stowage. Biomedical DSOs focus on operational concerns, including space motion sickness, cardiovascular deconditioning, muscle loss, changes in coordination and balance strategies, radiation exposure, pharmacokinetics and changes in the body’s biochemistry.

Many of the SLS-2 experiments were conducted in whole or in part on the SLS-1 mission. Contrary to the consistent repeatability of the physical and chemical sciences, studies of physiological systems involve variations in responses from one individual to another. To reduce the influence of the biological variability and to improve the quality of the experimental results, data are collected on multiple individuals and compared through statistical analysis. The SLS-2 mission not only contributed to the statistical assessment of those portions of the experiments performed on SLS-1 but also extended the data collection to studies and procedures being performed for the first time in the flight environment.