It's another small sliver of information in the expanse of mystery surrounding Malaysia Airlines Flight 370.

A failed satellite phone call suggests the missing passenger jet may have turned south slightly earlier than previously thought during its enigmatic journey, Australian authorities said Thursday.

But despite the new information, the general search area for the aircraft in the southern Indian Ocean "remains the same," Australian Deputy Prime Minister Warren Truss said at a news conference in the Australian capital, Canberra.

He explained that after Flight 370 dropped off radar on March 8, Malaysia Airlines ground staff tried to make contact with the plane using a satellite phone.

The attempt was unsuccessful, Truss said, but subsequent analysis of the failed call has given experts a better idea of the aircraft's position and where it was traveling.

MH370 vanished with 239 people on board during a flight that was meant to go from Kuala Lumpur, Malaysia, to Beijing. The search operation, described by Australian officials as the largest in history, has so far turned up no debris from the plane.

International aviation experts have relied on information from radar and satellites to try to plot the Boeing 777's course, concluding that it went down in a remote part of the southern Indian Ocean, far off Australia's west coast.

The experts are sticking to the same vast search zone announced in June, Truss said at the news conference Thursday.

But some of the information the analysts now have suggests that areas a little to the south may be of "particular interest," he said, noting that the zone continues to be refined as experts keep reviewing the available data.

Flight 370 was last detected by radar flying northwest over the sea between Peninsular Malaysia and the Indonesian island of Sumatra.

A series of subsequent communications between satellite systems and the errant plane -- known as "handshakes" -- determined that at some point MH370 turned south toward the southern Indian Ocean.

It was initially assumed that the southern turn took place at the northwestern tip of Sumatra. But the team of experts has since said there's no conclusive evidence about where the turn to the south took place.

To calculate the current search area, they said they took two approaches to the uncertainty surrounding the turn. They analyzed the satellite data using a range of assumed locations for the turn, and also without any assumption for where the turn took place.

The final radar detection of MH370, by the Malaysian military, occurred nearly an hour after the plane had veered off its planned course. Three minutes later, a satellite handshake indicated that the plane was still traveling northwest.

The unanswered phone call took place fourteen minutes after the handshake, according to information previously released by Australian authorities. Just over an hour later, a second handshake suggested that plane had turned and was heading south or southeast.

It's unclear from Truss' comments Thursday how much more clarity the analysts now have on the timing and location of the turn.

The crucial question of why the aircraft flew wildly off course also remains unanswered. Without the aircraft's wreckage and flight recorders, investigators are struggling to piece together what happened.

(CNN)