China is all set to send a three-person crew to its under-construction space station on Tuesday in a bid to embark upon its ambitions of hosting a permanently inhabited space station soon. The Shenzhou-15 crewed spaceship will be launched from the Jiuquan Satellite Launch Centre in northwest China, the China Manned Space Agency (CMSA) announced on Monday.?

The announcement comes amidst intensifying competition with the United States, and other nations, wherein many have hopped on a race to conquer space, by deploying sovereign space stations. Against this backdrop, earlier this year, India too announced an ambitious plan to launch a space station before 2030. Here’s all you need to know about space stations and what is the significance for the countries hosting one:

What are space stations and how are they useful?

A space station is a spacecraft-like artificial structure capable of supporting human habitation in space for an extended period of time. Usually stationed in the Lower Earth Orbit (LEO), it also provides an avenue for other spacecraft to dock.

According to a Britannica study, space stations can serve as the host country’s base for a myriad set of activities, ranging from resource mapping to surveillance as they offer unique views to study the Earth's weather, landforms, vegetation, oceans and atmosphere. They are also significant in supporting crucial research and collection of scientific data, including studies on the effects of long-term space flight on the human body.?

As private interests hope to capitalize on space tourism and space flights become increasingly desirable around the globe, space stations’ role as a laboratory can enable its use for commercial purposes as well.?

In some cases, sovereign space stations function as a country’s ‘eye from the sky,’ which enables round the clock monitoring of friends and foes alike. This also has immense military applications as well as implications as nations run in the race to establish independent space stations.?

Which countries presently operate space stations?

At present, the International Space Station (ISS), a collaborative project between five space agencies, is the only operational and permanently inhabited space station. The ISS became operational in November 2000, and was a $100 billion project built together by NASA, European Space Agency, Russia’s ROSCOSMOS, Japan’s JAXA, and the Canadian Space Agency.?

It flies at an average altitude of 400 kilometers above Earth in the LEO and circles the globe every 90 minutes. Over the years, the ISS has achieved many milestones in scientific research that will aid future strides in space exploration. For instance, in 2018, NASA’s Cold Atom Lab became the first facility to produce a fifth state of matter in space, called a Bose-Einstein condensate. Earlier in 2016, a NASA astronaut sequenced DNA in space for the first time. Over 200 astronauts from 19 countries have been carried into space so far.?

The ISS is expected to cease operations by 2024 and by 2031, studies suggest that it will fall out of its orbit into the waters of the South Pacific Ocean. The space station will be descended into the South Pacific Oceanic Uninhabited Area (SPOUA), referred to as Point Nemo, which functions as a space cemetery for defunct and decommissioned space debris.?

Against this backdrop, earlier this year in January, NASA proposed a ‘transition plan’ for the ISS to “maximize returns” from the space station before 2031.?

Which nations have announced?autonomous space stations?

With the ISS’ lifespan quickly approaching an end, countries are once again caught up in a space race. While the US government is making efforts to push for extending the ISS’ life until 2031, countries including China, Russia, and more recently India have declared plans to have their own sovereign space stations in time to come.?

Amid escalating tensions between Russia and western nations in the aftermath of the Ukraine war, the Kremlin has said that it will terminate its association with the ISS by 2024. Furthermore, Moscow has also revealed that its space agency is working on an autonomous space station, which is expected to be launched by 2025.?

China has made considerable progress in making its space station, Tiangong, habitable and operational for 10 years. Tuesday’s launch of a crewed spaceship, which will stay in orbit until May 2023, will further this goal.The China Manned Space Program began in 1992 and aims to “construct China’s Space Station (CSS) to accommodate long-term man-tended utilization on a large scale.” Once functional, CSS in the LEO will be a key competitor to the ISS.?

In fact, in January 2022, Indian Space Research Organisation too announced plans to send a space station by 2030 in furtherance of the Gaganyaan mission, the country’s first manned space mission.?

What progress has been made on the Indian space station?

According to a press release, ISRO’s space station is anticipated to weigh about 20 tonnes, will be placed 400 km above the Earth in the LEO and serve as a facility where astronauts can stay for upto 15-20 days in space. It will be used to conduct microgravity experiments in space, including a study on the effect of weightlessness in the human body. ?

A space station is a natural progression after a country successfully sends and returns a crewed space flight, and hence ISRO plans to start work on the space station after Gaganyaan’s success. This will make India only the fourth country across the globe to achieve the feat of sending a manned space flight and hosting a space station.?

ISRO has initiated work on perfecting the ‘spadex’ technology, which is crucial for making the space station functional as it allows transferring humans from one spacecraft to another.

What are some challenges and concerns with establishing sovereign space stations?

India’s path towards operationalizing its own space station is fraught with many challenges. First and foremost, the construction and maintenance of a space station requires immense budgetary allocations. As per reports, NASA incurs $3 billion annually to maintain the ISS.?

Moreover, technological capabilities need to be significantly ramped up for any nation to single handedly build and operate a space station. For example, Russia’s withdrawal from the ISS can have dire consequences as Roscosmos has been responsible for making course corrections to the orbit of the ISS, which makes it possible to safeguard the station from space debris. Additionally, the Kremlin also ferries astronauts from the Earth and back. In this regard, each space agency has a specialized role to play in ensuring the continuity of the collaborative project, all of which can be cumbersome for one country to assemble independently.?

Finally, the race to space has also been critiqued by analysts who point to the risk of increasing space debris, which can be detrimental for critical satellites operating in space.?

Countries have also expressed reservations over the potential misuse of space stations for weaponizing and militarizing space and even raised alarm over possible space wars. For instance, the US government highlighted concerns with Tiangong station, which will be equipped with a robotic arm. The US emphasized that it “could be used in a future system for grappling other satellites.”