Introduction
The International Space Station (ISS) continues to serve as humanity's outpost in low Earth orbit, requiring regular maintenance to ensure its operational longevity. In an exciting development for space enthusiasts, NASA has announced comprehensive coverage of two upcoming U.S. spacewalks, designated as US EVA 94 and US EVA 95. Scheduled for January 8 and January 15, these extravehicular activities (EVAs) will involve NASA astronauts venturing outside the station to perform critical tasks. These spacewalks underscore the ongoing commitment to the ISS program, even as the station approaches its planned deorbit in 2030. According to NASA's official news release, the first spacewalk on January 8 will begin at 8 a.m. EST and last approximately six hours and 30 minutes, with live coverage starting at 6:30 a.m. EST NASA News Release.
Background on ISS Spacewalks
Spacewalks, or EVAs, have been a cornerstone of the ISS program since its assembly began in 1998. These high-risk operations allow astronauts to perform repairs, upgrades, and installations that cannot be done from inside the station. Historically, the U.S. has conducted numerous EVAs, with the numbering system tracking American-led spacewalks. For context, the first U.S. spacewalk on the ISS occurred in 1998 during STS-88, when astronauts installed the Unity module NASA ISS Elements. Over the years, these activities have evolved from construction to maintenance, including battery replacements and solar array enhancements.
The ISS, a collaborative effort involving NASA, Roscosmos, ESA, JAXA, and CSA, orbits Earth at an altitude of about 250 miles (400 kilometers) and travels at 17,500 mph (28,000 km/h) NASA ISS Overview. Spacewalks are essential for sustaining this $150 billion orbital laboratory, which has hosted over 3,000 research investigations from more than 108 countries since 2000 NASA ISS Research. Recent EVAs have focused on upgrading power systems, as seen in 2023 when astronauts installed new International Space Station Roll-Out Solar Arrays (iROSAs) to boost energy efficiency NASA Solar Arrays Feature.
Details of US Spacewalks 94 and 95
US EVA 94 is set for January 8, with astronauts expected to exit the Quest airlock for a duration of around 6.5 hours. The second, US EVA 95, follows on January 15, maintaining a similar timeline. NASA will broadcast both events live on NASA Television, the agency's website, and the NASA app, starting coverage 90 minutes before each spacewalk begins NASA News Release. These spacewalks are part of Expedition 72, the current crew rotation on the ISS, which includes a mix of NASA astronauts and international partners.
Preparation for these EVAs involves rigorous training on Earth, including simulations in NASA's Neutral Buoyancy Laboratory, a massive pool that mimics microgravity NASA NBL Overview. Astronauts wear Extravehicular Mobility Units (EMUs), spacesuits weighing about 280 pounds (127 kg) on Earth but neutrally buoyant in space, providing life support for up to eight hours NASA Spacesuit Facts.
Astronaut Profiles
The astronauts participating in these spacewalks are seasoned professionals from NASA's corps. For US EVA 94 and 95, the primary spacewalkers are expected to include NASA astronauts Matthew Dominick and Michael Barratt, based on current Expedition 72 crew assignments NASA Expedition 72. Matthew Dominick, a U.S. Navy test pilot, is on his first spaceflight. Selected as an astronaut in 2017, Dominick holds degrees in electrical and systems engineering and has logged extensive hours in high-performance aircraft NASA Astronaut Bio: Matthew Dominick.
Michael Barratt, a veteran astronaut and physician, brings a wealth of experience. This is his third spaceflight, having previously conducted EVAs during Expedition 19/20 in 2009 and STS-133 in 2011. Barratt, who joined NASA in 2000, specializes in aerospace medicine and has contributed to medical research on the ISS NASA Astronaut Bio: Michael Barratt. Supporting roles may involve Jeanette Epps or Tracy C. Dyson, both of whom have EVA training and are part of the current crew rotation NASA Expedition 72.
Objectives and Tasks
The primary objectives of these spacewalks revolve around maintenance and upgrades to the ISS's power and communication systems. Specifically, astronauts will focus on removing and replacing a faulty radio communications component and conducting microbial sampling on the station's exterior. These tasks are crucial for ensuring reliable data transmission and studying how microorganisms survive in space, which has implications for planetary protection in future missions NASA News Release.
In addition, the EVAs may include preparations for future installations, such as routing cables for new scientific instruments. Technical details include working with the station's truss structure, where solar arrays generate up to 120 kilowatts of power NASA Solar Arrays. The microbial sampling involves collecting samples from the station's hull to analyze biofilm growth, building on studies like the 2019 Microbial Tracking-2 investigation NASA Microbial Tracking.
Technical Analysis
From a technical standpoint, these spacewalks highlight the challenges of operating in the vacuum of space. Astronauts must contend with extreme temperatures ranging from -250°F (-157°C) in shadow to 250°F (121°C) in sunlight, managed by the EMU's thermal control system NASA Spacesuit Facts. The tasks require precise coordination, using tools like the Pistol Grip Tool, a battery-powered device for torquing bolts with accuracy to within 0.1 foot-pounds NASA Pistol Grip Tool.
Analysis of past EVAs shows a success rate of over 95% for U.S. spacewalks, with contingencies in place for issues like suit malfunctions, as occurred during EVA 23 in 2013 when water leaked into an astronaut's helmet NASA EVA Mishap Report. For these upcoming EVAs, NASA has implemented enhanced safety protocols, including real-time monitoring from the Johnson Space Center.
Implications for Future ISS Missions and Beyond
These spacewalks are not just routine maintenance; they have broader implications for the ISS's role in preparing for deep space exploration. By ensuring the station's power and communication systems remain robust, NASA is facilitating ongoing research that informs the Artemis program, which aims to return humans to the Moon by 2026 NASA Artemis. Microbial studies from these EVAs could influence habitat designs for Mars missions, where contamination control is vital.
Industry-wide, the spacewalks highlight the growing commercialization of low Earth orbit. With companies like Axiom Space planning private modules for the ISS by 2026, these maintenance activities ensure a stable platform for public-private partnerships Axiom Space Station. Looking ahead, as the ISS nears retirement, lessons from EVAs 94 and 95 will inform the design of future orbital outposts, such as NASA's proposed Lunar Gateway NASA Gateway. Speculation suggests that advancements in robotic assistance could reduce human EVA risks in the future, though this remains unconfirmed without specific program announcements.
Conclusion
As NASA gears up for US Spacewalks 94 and 95, the space community watches with anticipation. These EVAs exemplify the dedication required to maintain our foothold in space, blending human ingenuity with cutting-edge technology. For space enthusiasts, tuning into the live coverage offers a front-row seat to history in the making. With the ISS paving the way for lunar and Martian ambitions, these activities remind us of the collaborative spirit driving space exploration forward.
