Juliette Collen
AFP
Juliette Collen wrote this article in AFP:
China's rogue rocket is in an uncontrolled free-fall towards Earth and no one knows where or exactly when it will burn through Earth's atmosphere, but the risk of debris hitting an inhabited area remains very small, experts told AFP on Friday.
- What happened?
On April 29, China launched the first module of its "Heavenly Palace" space station, a milestone in Beijing's ambitious plan to establish a permanent human presence in space.
The module was propelled by a powerful Long March 5B rocket, whose first stage is currently descending Earthward.
If Chinese ground engineers have no control over the booster stage's trajectory, it is not due to a technical failure or some unexplained glitch. The rocket was designed that way.
From a low Earth orbit, bodies are drawn gradually by gravity towards the surface of the planet. Such objects are usually consumed by heat as friction from an increasingly dense atmosphere increases on approach.
But the Long March rocket is so massive -- up to 18 tonnes -- that is it unlikely to burn up entirely.
- Likely scenarios?
The most likely landing zone is water, simply because nearly three-quarters of the surface of the planet is covered by oceans.
"The chances of debris landing on an inhabited zone are tiny, probably one in a million," said Florent Delefie, an astronomer at the Paris-PSL Observatory.
Even if fragments of the rocket do land on buildings, the speed of impact will be relatively slow at about 200 kilometres per hour (125 miles per hour). By comparison, a meteorite can reach speeds of 36,000 km/hr as it hurtles towards Earth.
NASA estimates that there are about 34,000 objects of at least 10 centimetres (four inches) in diameter circling Earth's today.
Since the beginning of the space age more than 60 years ago, some 6,000 objects have made an uncontrolled re-entry into Earth's atmosphere, and only once has any debris struck a human being. Even then it did not result in injury, according to Stijn Lemmens, an expert at ESA.
China's rogue rocket is in an uncontrolled free-fall towards Earth and no one knows where or exactly when it will burn through Earth's atmosphere, but the risk of debris hitting an inhabited area remains very small, experts told AFP on Friday.
- What happened?
On April 29, China launched the first module of its "Heavenly Palace" space station, a milestone in Beijing's ambitious plan to establish a permanent human presence in space.
The module was propelled by a powerful Long March 5B rocket, whose first stage is currently descending Earthward.
If Chinese ground engineers have no control over the booster stage's trajectory, it is not due to a technical failure or some unexplained glitch. The rocket was designed that way.
From a low Earth orbit, bodies are drawn gradually by gravity towards the surface of the planet. Such objects are usually consumed by heat as friction from an increasingly dense atmosphere increases on approach.
But the Long March rocket is so massive -- up to 18 tonnes -- that is it unlikely to burn up entirely.
- Likely scenarios?
The most likely landing zone is water, simply because nearly three-quarters of the surface of the planet is covered by oceans.
"The chances of debris landing on an inhabited zone are tiny, probably one in a million," said Florent Delefie, an astronomer at the Paris-PSL Observatory.
Even if fragments of the rocket do land on buildings, the speed of impact will be relatively slow at about 200 kilometres per hour (125 miles per hour). By comparison, a meteorite can reach speeds of 36,000 km/hr as it hurtles towards Earth.
NASA estimates that there are about 34,000 objects of at least 10 centimetres (four inches) in diameter circling Earth's today.
Since the beginning of the space age more than 60 years ago, some 6,000 objects have made an uncontrolled re-entry into Earth's atmosphere, and only once has any debris struck a human being. Even then it did not result in injury, according to Stijn Lemmens, an expert at ESA.
