Beijing, March 27: China's first experimental space lab is expected to fall back to Earth between March 31 and April 4 and should burn up in the atmosphere, space authorities said. Tiangong-1 has officially stopped sending data and entered its final phase of life on March 16, a statement issued yesterday by the China Manned Space Engineering Office said.

The Tiangong, or Heavenly Palace, is orbiting at an average height of about 216.2 km, the announcement noted but did not disclose any re-entry location. It is impossible to name the exact re-entry location at this stage, a Chinese aerospace expert told state-run 'Global Times'.

The approximate re-entry location cannot be decided until the last two hours before it starts to fall based on international precedents, he said. The lab will likely enter the atmosphere between March 31 and April 4, according to Beijing Aerospace Control Centre and other agency estimates. The China Manned Space website will supply daily updates.

Launched in September 2011, Tiangong-1 an experimental had a design life of two years. The heavenly vehicle successfully docked with the Shenzhou-8, Shenzhou-9 and Shenzhou-10 spacecraft and undertook a series of experiments. The lab completed its main missions following Shenzhou-10's return in June 2013. During its extended flight, Tiangong-1 conducted experiments in space technology, space-earth remote sensing and space environment exploration, the office said. China plans to finalise its space station to rival Mir, the Russian space station currently in orbit by 2022.