in low-earth orbit. Giving the International Space Station a neighbor. And it's working

on a tight deadline, because once that rocket lifts off, the countdown begins. That's

because the space agency hopes to finish the station by 2022, marking an ambitious plan

to push the boundaries of the country's human spaceflight program.

China is no stranger to building space stations and this latest attempt will actually be its

third one. The country has launched two previous experimental space laboratories: Tiangong-1

and Tiangong-2. Translating to “heavenly palace”, Tiangong-1 was the country's

first ever prototype space station that launched in 2011.The space station was in orbit for

a few years and even had multiple visits from Chinese astronauts known as taikonauts until

CMSA lost contact with it after a technical issue in 2016.

Eventually, Tiangong-1 had to come down, but no one knew exactly where it would land. Luckily

for everyone, it re-entered over the Pacific Ocean in the spring of 2018. Their second

attempt, Tiangong-2 was more successful, as it far surpassed its planned two-year lifespan.

It was then deliberately deorbited in 2019 after giving the scientists the data they needed.

But now it's time for a new space station and it begins with the launch of the first

module, Tianhe-1. Translating to “joining of the heavens'', this core component is the

most crucial part. It's the main living space and life support system that's designed

for up to three astronauts for a stay of about six months. On top of that, the module will

also provide the propulsion and power element of the station.

And while Tianhe-1 is the first module to launch, it won't be the last, as it's

part of a multi-module space station design. The other components will be dedicated

to conducting science experiments in microgravity. But to complete the station, an additional

11 flights are planned all throughout 2022. And well, that's already much less than

the more than 30 missions it took to build the ISS over the span of a decade. So, talk

about crunch time. Now, as for its ride, Tianhe-1 will be launching

on a Long March 5B rocket. It's China's latest version of its most powerful rocket,

the Long March 5 and can carry up to 25 metric tons of cargo into low-earth orbit. Standing

at roughly 53 meters tall, the rocket is crucial to China's space program as it was designed

specifically to haul the many components of its space station. So to launch these massive

payloads, the rocket produces roughly 10,600 kilonewtons of thrust. That's thanks to

the rocket's two core engines powered by cryogenic liquid hydrogen and four strapon boosters.

But what's unique about the Long March 5b rocket is that it doesn't have a second

stage. So during launch, this means that the rocket's four strapon boosters are the ones

that provide most of the thrust at liftoff. After those engines detach, the core's main

engines take over and push the cargo into orbit for payload separation.

And because the rocket doesn't have reignitable engines, that means that the core will eventually

re-enter the atmosphere and, wait for it... in an uncontrolled way. And while you might

be worried about that happening in the future, newsflash, it's happened before. Back in

2020, a Long March 5b core had an uncontrolled reentry over the Atlantic Ocean, allegedly

just missing New York City.

As for launch day, Tianhe will lift off from Wenchang Satellite Launch Center, on the island

of Hainan. And this will be the first step, because after its launch, there will be a

flurry of rockets just waiting to take to the skies to try and complete the station by the ambitious deadline, with taikonauts already training to head up to their new space

dwellings. Their launch dates are still unknown, but hey, better to be ready than never.

For more Countdown to Launch, check out our playlist here.

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let us know in the comments below.

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