Does anyone know since when we are close to building in space?

We have been actively contemplating and working towards building in space for a considerable period, with origins tracing back to the early days of space exploration. While the grand visions of O'Neill Cylinders from the 1960s and 70s are not yet a reality, the foundational steps for practical space construction have been achieved, and the field is advancing rapidly towards more ambitious construction projects in the near future.

Early Concepts and Milestones (1950s-1970s)

In the 1950s, directly following the dawn of the space age, discussions around space construction began. This era saw the emergence of significant theoretical contributions, such as Gerard O'Neill's space colony proposals, famously the O'Neill Cylinders, in the 1960s and 70s. These concepts envisioned large orbital habitats for human habitation and industrial activities. NASA's early Space Station Program plans in the 1960s also laid some groundwork, even if not fully realized at the time.

Initial Steps and The International Space Station (1970s-Present)

The 1970s marked the launch of NASA's Skylab (1973), the first U.S. space station, demonstrating that large structures could be utilized in space. The Soviet Mir space station (1986-2001) further proved the feasibility of long-term human presence and modular system maintenance in orbit. The Space Shuttle Program (1981-2011) was crucial for transporting heavy payloads and crew, becoming a prerequisite for later construction efforts. However, the most definitive proof of our ability to build in space is the International Space Station (ISS). Its assembly, which began in 1998 and continued over two decades, is a testament to modular construction and collaborative in-orbit building.

Modern Era and Future Prospects (2000s-Present)

Today, we are witnessing a crucial shift from simply launching pre-built modules to embracing in-situ construction, manufacturing, and assembly in orbit. This is largely driven by:

• ·Private Space Companies: Companies like SpaceX and Blue Origin are making space access more affordable and frequent with reusable rocket technology.
• ·In-Orbit Manufacturing and 3D Printing: Companies like Made In Space (now Redwire) have demonstrated 3D printing in space on the ISS, creating tools and spare parts. Projects like Archinaut aim for autonomous robotic assembly.
• ·Robotic Assembly: The use of robotic arms like Canadarm2 on the ISS, and the development of new autonomous robotic systems, are critical for assembling larger and more complex structures.
• ·In-Space Assembly (ISA) Techniques: These techniques, exemplified by the unfolding of the James Webb Space Telescope's mirror, are becoming increasingly sophisticated.

Current and Upcoming Projects:

• ·Lunar and Mars Habitats: NASA's Artemis program plans to establish a sustainable human presence on the Moon, serving as a stepping stone for Mars exploration. SpaceX's Starship is also key to this endeavor.
• ·Commercial Space Stations: Companies like Axiom Space and Bigelow Aerospace are developing commercial platforms for research, manufacturing, and tourism.
• ·Large Space Solar Power Satellites: While still largely conceptual, the idea of building massive solar power arrays in orbit is gaining traction.
• ·Orbital Construction Facilities: Ventures like ThinkOrbital's ForgeStar aim to establish dedicated facilities for construction in space.

We are increasingly close to systematic, large-scale construction in space, driven by the need to reduce launch mass and cost, and to enable structures impossible to launch fully assembled. The focus is shifting towards autonomous robotic assembly, in-situ resource utilization (ISRU) leveraging lunar or asteroid materials, and the development of permanent, expandable, and self-repairing infrastructure for power, science, and commercial use within the next decade.