A Chilean jetliner approaching New Zealand came within 20 seconds of being hit by blazing objects hurtling down to Earth, New Zealand aviation officials say.

US space officials said today it was most likely a close encounter with a disintegrating meteor, denying assertions from New Zealand officials that the LAN Chile plane narrowly missed being blasted by Russian space debris that was returning to Earth ahead of schedule.

While it is not uncommon for space junk to fall into the South Pacific, "it is very uncommon to have a plane in the middle of it," said Airways New Zealand spokesman Ken Mitchell.

Mitchell, whose agency handles air traffic control in the region, told New Zealand National Radio that the flaming objects were likely space junk arriving 12 hours ahead of Russian projections.

The airline said in a brief communique that the pilot, who was not identified, "made visual contact with incandescent fragments several kilometres away" during the Monday night flight, and that the incident was reported to authorities in Chile and New Zealand.

But Russia's Federal Space Agency issued a statement saying that its cargo ship Progress M-58 had fallen back to Earth according to the timetable it had warned aviation officials about previously.

In other words, the Russians say the fragments of Progress didn't plunge into the Pacific Ocean east of New Zealand until about around 2330 GMT Tuesday. The fiery near-hit with the jet was reported about 12 hours earlier, a time when the cargo ship was still attached to the international space station.

"Unless someone has their times wrong, there appears to be no correlation," said Nicholas Johnson, orbital debris chief scientist for NASA's Johnson Space Centre.

Johnson said there are no other reports from the US Space Surveillance Network of other re-entering space junk at the time, so the flaming objects must have been fragments of a meteor.

The Lan Chile pilot flying from Santiago, Chile, notified air traffic controllers at Auckland after spotting the flaming objects just five nautical miles (9.2 kilometres) in front of and behind his Airbus 340.

That distance would not have given the pilots much room for manoeuvre, according to World Airliner magazine editor Tony Dickson. "You're talking about 20 seconds and that's not a lot" of separation, he told National Radio Thursday.

About 50 meteoroids enter the Earth's atmosphere every day - mostly burning up as they speed in - said Bill Ailor, director of the Centre for Orbital and Reentry Debris Studies at the Aerospace Corporation of El Segundo, Calif.

Those that survive to hit the earth are called meteorites.

By contrast, about 150 pieces of man-made space junk fall back to Earth each year. About two-thirds of these are unplanned but still known and monitored, and larger man-made space equipment, such as the Progress resupply ship, have motors to guide them back to Earth, Ailor said.

If they are calculated to have more than a 1 in 10,000 chance of hitting people, they are shifted to a safer path, he said, though small errors can lead to large variations in where the debris hits.

"For de-orbit, everything has to be lined up right ... and your math has to be right and also your time has to be precise," Ailor said. "There are lots of places where you can have problems."

No one has ever been killed by man-made space junk, Ailor said, though in 1997, an Oklahoma woman was grazed in the shoulder by falling material.