MH370 found its way to Antarctica

On July 29th, a part of the wreck was washed up off the island of Reunion Island. A week later, the Malaysian government announced: Maintenance documents from Malaysia Airlines would clearly show that it was a rudder of the missing Boeing 777. The French authorities, which are currently investigating the wreckage, did not confirm this, but speak of "strong indications".

What does the wreckage mean for the search?

Experts value the first part of the wreck as an important clue in the difficult and so far costing 120 million euros search for the Malaysia Airlines plane that disappeared almost 17 months ago. Current models show that wreckage from the suspected crash area could be washed to exactly where the rudder was found. Experts are now trying to calculate back how the wreckage came to La Réunion.

In this respect, the find encourages the specialists that at least they are not looking in the wrong place. The 12,000 square kilometer search corridor cannot be narrowed down any further thanks to the partial wreckage.

Why can't the search area be restricted?

The sea in the search region does not flow in one direction like a river. There are significant currents that cause the wreckage to drift and swirl it for thousands of kilometers along the ocean floor. "There are smaller currents everywhere in the sea," says Detlef Quadfasel, professor at the Institute for Oceanography at the University of Hamburg, "but they change a lot over time." The wreckage therefore does not take the straight path along the main flow. "It is drifting with the mean current," says Quadfasel, "but the part is always torn back and forth. The ocean is pretty chaotic."

That is why it is impossible for scientists to calculate the exact route. The eddies in the ocean can be calculated better than with the weather, but no statements are possible over a period of 17 months, says Quadfasel. There is no trace of the wreckage as a carpet of rubble in the water.

How did the part of the wreck get to shortly before Africa?

With the help of the ocean current. This is mostly caused by wind and the tides on the surface, but can also occur in deeper sea areas due to differences in water temperature or salinity. In the Indian Ocean there is the Agulhas Current, named after Cape Agulhas, the southernmost point of Africa. This is a large vortex that rotates counterclockwise between Australia, Africa and Antarctica. "It's about a thousand kilometers wide, wind-driven ocean current," says Quadfasel. "The current flows at a typical speed of ten centimeters per second." In this way, the part of the wreck could have been driven in the past 17 months until shortly before Madagascar.

Which parts can a sea current transport?

The rudder and the window part recently found according to the Malaysian government - reports from Kuala Lumpur have also found an airplane window and pieces of aluminum on La Réunion, but Paris denies this - are rather small parts compared to the overall size of a Boeing 777. But a sea current can also transport large parts.

"If the wreck can swim freely and is not broken, the whole plane could drift through the sea," says Quadfasel. Once the wreck has reached the bottom of the sea, however, it is unlikely that it will be moved again. "The wreck will probably have shattered on impact," says Quadfasel, "one part will then have sagged, another part, especially the isolated parts in which air is trapped, will then drift around."

What do the shells on the wreckage mean?

Researchers at the University of Cologne believe they have recognized barnacles on the washed up steering wheel. The organisms can also give an indication of the crash site.

Barnacles are small crustaceans. They drift on the surface until they settle on a solid object - that can also be a part of the wreckage drifting past. A cold-loving species of barnacle that Lepas australis, lives only in temperate waters in the southern hemisphere. "It must now be investigated whether this species can be found on the part of the wreck," says Hans-Georg Herbig, Professor of Paleontology at the University of Cologne, "then that would be an indication that the aircraft really flew south and southwest must have crashed from Australia. "

Why is it so difficult to search in the Indian Ocean?

The search area is located in one of the most inhospitable marine regions in the world, between Australia, South Africa and the Antarctic, thousands of kilometers from any land mass. The current in the area is one of the strongest in the world and the waves can reach heights of up to nine meters. The sea floor is up to 6000 meters deep and very rugged in places. Nobody knows the exact depth because it has not yet been measured. The US ocean floor specialist Walter Smith from the National Oceanic and Atmospheric Administration's Laboratory in Maryland said the knowledge is significantly less "than that about the moon, Mars and Venus."

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