According to a plane spotter, who was tuning into a high frequency radio broadcast at the time, the pilot "reported that the rumbling noise from the space debris could be heard over the noise of the aircraft. "He described he saw a piece of debris lighting up as it re-entered [the earth's atmosphere].

"He was one very worried pilot, as you would imagine. "Auckland is talking to [an] Aerolineas Argentinas [pilot] who is travelling [in the] opposite direction at 10 degrees further south asking if they wish to turn back to Auckland. "They have elected to carry on at the moment.

"[It's] not something you come across everyday and I am sure the Lan Chile crew will have a tale to tell." The assistant secretary of the Australian and International Pilots Association, Captain Steven Anderson, who flies for Qantas, said that based on the details of the report, the debris could have caused catastrophic consequences had it actually struck the aircraft.

"For [the pilot] to have heard it, one of two things - [the debris] was a lot closer than he thinks or it was bigger and going at quite a high speed. "In other words, it's caused the piece to break the speed of sound which is what he's heard - the sound barrier.'' A spokesman for Airways New Zealand, which provides air navigation services across airspace known as the Auckland Flight Information Region, confirmed the incident to smh.com.au this morning.

He said it occurred about 10 minutes after the Lan Chile flight had entered the Auckland Flight Information Region. Airways New Zealand had been warned by Russian authorities almost two weeks ago that a satellite would be entering the earth's atmosphere sometime today between 10.30am and midday [NZ time].

Airways New Zealand then provided that information to airlines and pilots that would be travelling in that region at that time. They could then decide for themselves whether they wished to fly during that period. "But clearly there has been a timing issue," the spokesman said.

"Either the time that was indicated to us was incorrect or the satellite de-orbited early." Because the timing was wrong, the coordinates of where the satellite was supposed to enter the Earth's atmosphere also turned out to be incorrect.

A formal report about the incident has been logged and recordings of conversations between the pilot and air traffic controllers were expected to be handed over to investigators in the next few days, he said. The Lan Chile flight landed safely at Auckland Airport at 3.55am today, he said. The Airways New Zealand spokesman was not aware of the name of the Russian satellite but it was likely to have been the Russian Progress 23P cargo freighter.

The unmanned spacecraft left the International Space Station on Tuesday and was due to burn through the upper layers of the Earth's atmosphere over the Pacific Ocean about 11.20am today [NZ time], the Spaceflight Now website reports. The Russian Progress 23P had docked at the ISS last October to supply fuel, oxygen and repair parts, it said.