Beijing's failure to share the details of the rocket's descent over the Indian Ocean was irresponsible and risky, says NASA.

Long March 5B blasted off July 24 to deliver a laboratory module to the new Chinese space station under construction in orbit.
Long March 5B blasted off July 24 to deliver a laboratory module to the new Chinese space station under construction in orbit. (Reuters file)

A Chinese rocket has fallen back to Earth over the Indian Ocean but NASA said Beijing had not shared the "specific trajectory information" needed to know where possible debris might fall.

US Space Command said the Long March 5B re-entered over the Indian Ocean at approximately 12:45 PM EDT (1645 GMT), but referred questions about "reentry’s technical aspects such as potential debris dispersal impact location" to China.

"All spacefaring nations should follow established best practices and do their part to share this type of information in advance to allow reliable predictions of potential debris impact risk," NASA administrator Bill Nelson said. 

"Doing so is critical to the responsible use of space and to ensure the safety of people here on Earth."

Social media users in Malaysia posted video of what appeared to be rocket debris.

Aerospace Corp, a government funded nonprofit research center near Los Angeles, said it was reckless to allow the rocket's entire main-core stage – which weighs 22.5 tonnes – to return to Earth in an uncontrolled reentry.

READ MORE: Large Chinese rocket segment lands near Maldives in Indian Ocean

China: Debris won't risk anyone

Earlier this week, analysts said the rocket body would disintegrate as it plunged through the atmosphere but is large enough that numerous chunks will likely survive a fiery re-entry to rain debris over an area some 2,000 km long by about 70 km wide.

The Chinese Embassy in Washington did not immediately comment. 

China said earlier this week it would closely track the debris but said it posed little risk to anyone on the ground.

The Long March 5B blasted off July 24 to deliver a laboratory module to the new Chinese space station under construction in orbit, marking the third flight of China's most powerful rocket since its maiden launch in 2020.

The Tiangong space station is one of the crown jewels of Beijing's ambitious space programme, which has landed robotic rovers on Mars and the Moon, and made China only the third nation to put humans in orbit.

The new module, propelled by the Long March 5B, successfully docked with Tiangong's core module on Monday and the three astronauts who had been living in the main compartment since June successfully entered the new lab.

China has poured billions of dollars into space flight and exploration as it seeks to build a program that reflects its stature as a rising global power.

READ MORE: China's rocket out of control but debris unlikely to cause any harm

Source: Reuters