Bharatiya Antariksha Station

The Indian Orbital Space Station, officially called, Bharatiya Antariksha Station (lit. 'Indian Space Station'),  (ISO: ) is a planned modular space station to be constructed by India and operated by the Indian Space Research Organisation (ISRO). The space station would weigh 52 tonnes and maintain an orbit of approximately 400 kilometres above the Earth, where astronauts could stay for 15–20 days. Originally planned to be completed by 2030, it was later postponed to 2035 due to delays caused by technical issues related with the Gaganyaan crewed spaceflight mission and the COVID-19 pandemic in India. As of December 2023, the first module is expected to be launched in 2028 on an LVM3 launch vehicle, with the remaining modules to be launched by 2035 on the Next Generation Launch Vehicle.

History
In 2019, ISRO chief K. Sivan presented the features of the proposed space station for the first time, saying that the space station may weigh up to 20 tons. Three years later, in his New Year's speech delivered before retiring as chairman, Sivan stated that India's first crewed spaceflight project Gaganyaan had completed the design phase and entered into the testing phase, hinting that the organization has achieved a breakthrough in reaching the space mission milestone.

In 2023, chief S. Somanath said: "Our Gaganyaan programme is towards a human space flight capability to space and once that happens, we will be able to look at space station building in subsequent modules. The timeline for this space station project spans the next 20 to 25 years. We will be definitely looking at manned exploration, a human spaceflight for a longer duration, space exercise there in our agenda". Following on from the Gaganyaan project, completing the station and conducting a crewed Moon landing by the year 2040 has been set as ISRO's goal for the upcoming decade, with a whole host of new projects and undertakings to come up in support of the mission.

During his visit to India in November 2023, NASA administrator Bill Nelson expressed NASA's readiness to support India's goal of building a commercial space station by 2040 if India seeks such collaboration. This potential partnership could leverage the expertise and experience of both countries, fostering innovation and advancing human presence in space between the two Artemis Accords signatories. In December 2023, Somanath stated that ISRO had a 25-year roadmap extending to the year 2047. This included plans to launch the first space station module in 2028 and complete the station by 2035.

A polymer electrolyte membrane Fuel Cell Power System (FCPS) created by the Vikram Sarabhai Space Center (VSSC) was successfully launched by ISRO on 1 January 2024, as part of the PSLV-C58 mission. Its purpose is to evaluate the possible power supply for the future Indian Space Station. The PSLV Orbital Experiment Module, or POEM-3, will be used for technological validation. Additionally, new silicon-based high-power energy cells will be tested by VSSC.

The successful test of FCPS, a 100 Watt payload, onboard POEM-3 was reported by ISRO on 2 January 2024. Under high pressure, a chemical reaction was sparked using oxygen and hydrogen, when moved through a fuel cell assembly. It assisted in producing 180 Watt electricity and clean drinking water as byproduct. The complete system functioned as planned in radiation-filled, temperature-extreme, and weightless environment.

The next phase will be the construction of a 100 Kilowatt system. Fuel cells have already been constructed by ISRO and provided to other organizations for testing. The International Space Station (ISS) is already using this technology, but ISRO is working to broaden its application. On board POEM-3, the 10 Ampere-hour high-power energy cells based on silicon–graphite anode were also tested. These lithium-ion batteries are lightweight, have a compact design, and an improved energy density thanks to the silicon-graphite content. The energy cells have crimped sealing based design which reduces the hardware and fabrication costs. It is expected to save 35-40% of battery mass on future space missions.

The chairman of ISRO, S. Somanath revealed that he had been reviewing the designs of the Indian Space Station when speaking with media during India International Science Festival 2024. Developmental tests for the space station could begin from 2025. ISRO is planning to establish a basic, preliminary model of the space station in 2028 before building the larger, final version in 2035. The space agency is in discussions with industry to produce, evaluate, and introduce the first module by 2028.

ISRO will start testing docking capabilities in SPADEX mission, before being deployed on Chandrayaan-4 and future missions to Gaganyaan and Indian Space Station. A project report that includes all the information, a study and internal evaluation, and a cost estimate has been prepared and is about to be approved by the government.

Design
BAS is currently in the conceptualisation phase. ISRO is studying the overall architecture, including the number and types of modules and docking ports required for the project. The financial aspects are yet to be analysed.

The Bharatiya Antariksha Station will have 5 modules connected via the Common Berthing Mechanism. The entire station will have dimensions of 27m × 20m, and is estimated to have a mass of around 52 tonnes, significantly greater than the previously planned 25 tonnes. It will have a maximum short duration crew capacity of 6 astronauts and a nominal crew size of 3-4 astronauts. BAS will orbit between 400-450 km with an inclination of 51.6° making it accessible to American, Russian, Japanese as well as ESA's spaceports. The establishment of the Bharatiya Antariksha Station is poised to enhance India's presence in space research and exploration significantly as it will provide a unique platform for conducting scientific experiments in microgravity and foster advancements in space technology, potentially leading to economic activities based on lunar resources 2047.

According to ISRO Chairman S Somanath, the Indian Space Station is in the final stages of design as of February 2024. The electronics for the station will be produced at the U R Rao Satellite Centre (URSC) in Bengaluru, while Vikram Sarabhai Space Centre (VSSC) will help in hardware development.

Two to four astronauts could stay in space on the Bharatiya Antariksha Station. The crew module and rocket that will transport humans to and from the space station will dock at one end of the station. India is creating a unique docking port that will work with the International Space Station's docking port (ISS). At least four pairs of solar panels and four distinct modules are possible for the Indian Space Station once it is finished. In case of an emergency, it will also feature a permanently docked safety crew module escape system. According to the existing blueprints, the Bharatiya Antariksha Station would be powered by two sizable solar panels in the initial phase.

In June 2024, S Somanath informed NDTV about the completion of detailed design work for the space station's Phase-1 module, which is scheduled to launch on LVM3 in 2028. The complete project and cost estimate report is ready for government approval. The module will initially accommodate robotic operations. Human activity will start from 2035.