Malaysia Airlines flight 370: NOAA Seafloor experts publish new view of potential crash zone

This is the seafloor topography in the Malaysia Airlines flight MH370 search area. 

Dashed lines approximate the search zone for sonar pings emitted by the flight data recorder and cockpit voice recorder popularly called black boxes. 

The first sonar contact (black circle) was reportedly made by a Chinese vessel on the east flank of Batavia Plateau (B), where the shallowest point in the area (S) is at an estimated depth of 1637 meters. 

The next reported sonar contact (red circle) was made by an Australian vessel on the north flank of Zenith Plateau (Z). 

The deepest point in the area (D) lies in the Wallaby-Zenith Fracture Zone at an estimated depth of 7883 meters. 

The Wallaby Plateau (W) lies to the east of the Zenith Plateau. 

The shallowest point in the entire area shown here is on Broken Ridge (BR). Deep Sea Drilling Project (DSDP) site 256 is marked by a gray dot. 

Seafloor depths are from the General Bathymetric Chart of the Oceans [2010] (GEBCO). 

Credit: Walter H.F. Smith and Karen M. Marks

A new illustration of the seafloor, created by two of the world's leading ocean floor mapping experts that details underwater terrain where the missing Malaysia Airlines flight might be located, could shed additional light on what type of underwater vehicles might be used to find the missing airplane and where any debris from the crash might lie.

The seafloor topography map (above) illustrates jagged plateaus, ridges and other underwater features of a large area underneath the Indian Ocean where search efforts have focused since contact with Malaysia Airlines flight MH370 was lost on March 8.

The image was published today in Eos, the weekly newspaper of the Earth and space sciences, published by the American Geophysical Union (AGU).

The new illustration of a 2,000 kilometer by 1,400 kilometer (1,243 miles by 870 miles) area where the plane might be shows locations on the seafloor corresponding to where acoustic signals from the airplane's black boxes were reportedly detected at the surface by two vessels in the area. It also shows the two plateaus near where these "pings" were heard.

It points out the deepest point in the area: 7,883 meters (about five miles) underneath the sea in the Wallaby-Zenith Fracture Zone – about as deep as 20 Empire State buildings stacked top to bottom.

Undersea mountains and plateaus rise nearly 5,000 meters (about three miles) above the deep seafloor, according to the map.

This image, originally appeared on the NOAA map and it shows the possible crash area's location, to the west of Australia.

The illustration, designated as Figure 1 of the Eos article, was created by Walter H.F. Smith and Karen M. Marks, both of the (National Oceanic and Atmospheric Administration) NOAA's Laboratory for Satellite Altimetry in College Park, Maryland, and the former and current chairs, respectively, of the Technical Sub-Committee on Ocean Mapping of the General Bathymetric Chart of the Oceans, (GEBCO).

GEBCO is an international organization that aims to provide the most authoritative publicly available maps of the depths and shapes of the terrain underneath the world's oceans.

Satellite altimetry has made it possible to depict the topography of vast regions of the seafloor that would otherwise have remained unmapped, Smith said.

To illustrate the topography of the search area, Smith and Marks used publicly available data from GEBCO and other bathymetric models and data banks, along with information culled from news reports.

Smith said the terrain and depths shown in the map could help searchers choose the appropriate underwater robotic vehicles they might use to look for the missing plane.

Knowing the roughness and shape of the ocean floor could also help inform models predicting where floating debris from the airplane might turn up.

Smith cautions that the new illustration is not a roadmap to find the missing airplane. Nor does the map define the official search area for the aircraft, he added. "It is not 'x marks the spot'," Smith said of their map.

"We are painting with a very, very broad brush."

Search efforts for the missing airplane have focused on an area of the southern Indian Ocean west of Australia where officials suspect that the plane crashed after it veered off course.

After an initial air and underwater search failed to find any trace of the airplane, authorities announced this month that they will expand the search area and also map the seabed in the area.

Smith pointed out that the search for the missing plane is made more difficult because so little is understood about the seafloor in this part of the Indian Ocean.

In the southeast Indian Ocean, only 5 percent of the ocean bottom has been measured by ships with echo soundings.

Knowledge of the rest of the area comes from satellite altimetry, which provides relatively low-resolution mapping compared to ship-borne methods.

"It is a very complex part of the world that is very poorly known," Smith said.

More information: Paper: onlinelibrary.wiley.com/doi/10.1002/2014EO210001/pdf

New improved view of supernova explosion and death throes

Three-dimensional turbulent mixing in a stratified burning oxygen shell which is four pressure scale heights deep. 

The yellow ashes of sulphur are being dredged up from the underlying orange core. 

The multi-scale structure of the turbulence is prominent. 

Entrained material is not particularly well mixed, but has features which trace the large scale advective flows in the convection zone. 

Also visible are smaller scale features, which are generated as the larger features become unstable, breaking apart to become part of the turbulent cascade. 

The white lines indicate the boundary of the computational domain. 

Credit: Arnett, Meakin and Viallet/AIP Advances

A powerful, new three-dimensional model provides fresh insight into the turbulent death throes of supernovas, whose final explosions outshine entire galaxies and populate the universe with elements that make life on Earth possible.

W. David Arnett

The model is the first to represent the start of a supernova collapse in three dimensions, said its developer, W. David Arnett, Regents Professor of Astrophysics at the University of Arizona, who developed the model with Casey Meakin and Nathan Smith at Arizona and Maxime Viallet of the Max-Planck Institut fur Astrophysik.

Described in the journal AIP Advances, it shows how the turbulent mixing of elements inside stars causes them to expand, contract, and spit out matter before they finally detonate.

Arnett, a pioneer in building models of physical processes inside stars, traces his fascination with turbulence to 1987A, the first supernova of 1987.

Located in a nearby galaxy, it was bright enough to see with the naked eye.

The star puzzled astronomers, Arnett recalled, because the material ejected by its explosion appeared to mix with material previously ejected from the star.

Existing models could not explain that. "Instead of going gently into that dark night, it is fighting. It is sputtering and spitting off material. This can take a year or two. There are small precursor events, several peaks, and then the big explosion.

"Perhaps what we need is a more sophisticated notion of what an explosion is, to explain what we are seeing," Arnett concludes.

More information: The article, "Chaos and turbulent nucleosynthesis prior to a supernova explosion" by David Arnett, Casey Meakin and Maxime Viallet appears in the journal AIP Advances (DOI: 10.1063/1.4867384). 

The article will be published online on March 18, 2014. dx.doi.org/10.1063/1.4867384