Piecing together the puzzle of Pangea

Thick black and magenta lines show northern boundaries of India and Arabia and southern boundary of Eurasia. Dashed light-green line marks outer margin of Pangeides active margin. Dashed yellow line shows approximate boundary between active margin and arc of thick lithosphere. Dashed dark-green line outlines area underlain by thinner lithosphere that now underlies North Africa, Arabia, and western Europe. Inset shows same reconstruction without any lithospheric thickness contours. NA--North America;, Eu--Eurasia; SA--South America; Af--Africa; An--Antarctica; Au--Australia. Click image to expand. [Credit: McKenzie et al., Geology, Geological Society of America].

 

Scientists have pieced together the continent of Pangea (which mean "all land" in Greek) that existed 250 million years ago when all today's continents were joined together.

There aim was to determine the pattern of plate thickness before Pangea broke up and to compare it to today's plate thickness of continents that varies from about 90 kilometres beneath places like California or Western Europe, to more than 200 kilometres beneath the older interiors of the U.S., Eastern Europe, and Russia.

Authors Dan McKenzie, Michael C. Daly, and Keith Priestley were surprised to find the thick parts of the plates all came together to form a boomerang-shaped arc.

The outside of the boomerang consisted of a subduction zone where oceanic plates were returned to the mantle.

The inside of the boomerang consisted of a plate with a thickness of about 100 kilometres which was strongly deformed and heated about 600 million years ago.

Pangea itself was assembled from a number of different plates. The continental deformation that took place during this assembly must have been controlled by the plate thickness, since it produced a continuous boomerang shaped region of thick plate.

Their research was published as The lithospheric structure of Pangea by the geological Society of America.

Satellite captures giant algal bloom in North Sea

[Credit: NASA Earth Observatory images by Jesse Allen, using data from the Level 1 and Atmospheres Active Distribution System (LAADS)]

Phytoplankton blooms in the North Sea tend to be most abundant in late spring and early summer due to high levels of nutrients in the water and increased sunlight.

Conditions are ideal with the intense winds blowing over the relatively shallow sea bringing nutrients to the surface to combine with run-off from European rivers.

But now, sSome researchers have found that numbers of plankton can actually begin to increase in the middle of winter, when growth conditions would seem to be at their worst.

Studies suggest that winter storms churn the ocean and cause deep water mixing. This water mixing allows for phytoplankton to grow and live at depth without being spotted by their predators.

When spring arrives, phytoplankton can fully bloom because not only are the nutrients available, but there is a longer period of sunlight

The image above, acquired in June by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite, shows a mass of phytoplankton blooming between Denmark, the United Kingdom, and Germany. 

You can now listen to NASA Voyager’s ‘Golden Record’, intended for aliens & future humans, on Soundcloud

The Golden Record. [Credit: NASA/JPL]

The Golden Record. [Credit: NASA/JPL]

When NASA launched the Voyager 1 and 2 probes in 1977 to study the outer Solar System, they equipped them with an audio time capsule known as the ‘Golden Record’. The 12-inch golden phonographic record, which consists of sounds from life on Earth, was meant for any aliens or future humans to give them an auditory glimpse of what Earth was like in the 20th century.

And now NASA has treated present-day life on Earth to a treat – some of those recordings are now available on Soundcloud for your listening pleasure.

Artist's impression of Voyager 1. [Credit: NASA/JPL]

Artist's impression of Voyager 1. [Credit: NASA/JPL]

The snippets of the Golden Record recording include an assortment of sounds and audio: greetings from Earth in 50 ancient and modern languages, a crying baby being comforted by a mother, automobile sounds, animal noises, wind and rain, and Morse code. There’s also an electronic ‘Music of the Spheres’ recording, which imagines and emulates planetary motion as harmonies in a ‘celestial choir’ – inspired by Johannes Kepler’s Harmonices Mundi. And the Golden Record begins with an introductory statement by then US President Jimmy Carter.

It is also the same record that includes the brainwaves of Ann Druyan, who was collaborating on the Golden Record and falling in love with Carl Sagan at the time.

Both Voyager probes are currently on their way out to the star known as AC +79 3888 in their mission to explore interstellar space. Voyager 1 is believed to have passed the boundary of the heliosphere, the enormous magnetic bubble that encompasses our Solar System, and entered interstellar space in 2012 – though it will still take about 40,000 years for it to reach AC +79 3888.

You can view the real-time locations of both Voyagers on their NASA website.

Eight-year-old boy becomes the first kid ever to get a double hand transplant

Surgeons have successfully performed the first double hand transplant on eight-year-old Zion Harvey at the Children’s Hospital of Philadelphia (CHOP) in the US, just four years after the same surgical team performed the procedure on an adult patient in 2011.

A team of 40 physicians, nurses and surgeons from CHOP and Penn Medicine carried out the 10-hour surgical procedure earlier this month.

Zion, who’d had both his hands and feet amputated and later a kidney transplant due to a severe infection, waited three months after being put on the wait-list for a donor to come through.

“Each year, there are only 15 children, based on the databases, that would even be eligible to donate hands,” says lead surgeon L. Scott Levin in the Children’s Hospital video that tells the story of Zion’s transplant. “And then it comes down to the organ procurement organisations approaching families at a terrible time – the loss of a child. So the fact that he was put on the waiting list for hands in April, and three months later, this came along – that in and of itself is a remarkable story.”

Check out the video to watch the full story of bright little Zion and his new hands.


Hubble uses microlensing to find Uranus-sized planet around distant star

NASA’s Hubble Space Telescope and the W.M. Keck Observatory in Hawaii have independently confirmed the discovery of a giant exoplanet orbiting far from its central star. The planet was discovered through a technique called gravitational microlensing.

This findings were published in two papers in the The Astrophysical Journal.

The discovery is significant as most exoplanets found so far orbit very close to their host stars. Techniques for finding the distant worlds favour finding planets in these shorter orbits, which is why scientists are also the microlensing technique, which can find more distant and colder planets in long-period orbits.

Microlensing, explained in the video above, occurs when a foreground star amplifies the light of a background star that momentarily aligns with it.  If the foreground star has planets, then the planets may also amplify the light of the background star, but for a much shorter period of time than their host star. The exact timing and amount of light amplification can reveal clues to the nature of the foreground star and its accompanying planets.

The system where the giant was discovered has been cataloged as OGLE-2005-BLG-169. It was discovered in 2005. Now the Hubble and the Keck Observatory teams have found that the system consists of a Uranus-sized planet orbiting about 600 million kilometres from its parent star, slightly less than the distance between Jupiter and the Sun. The host star, however, is about 70% as massive as our Sun.

“These chance alignments are rare, occurring only about once every 1 million years for a given planet, so it was thought that a very long wait would be required before the planetary microlensing signal could be confirmed,” said David Bennett, the lead of the team that analysed the Hubble data.

“Fortunately, the planetary signal predicts how fast the apparent positions of the background star and planetary host star will separate, and our observations have confirmed this prediction. The Hubble and Keck Observatory data, therefore, provide the first confirmation of a planetary microlensing signal.”

Microlensing is such a powerful tool that it can uncover planets whose host stars cannot be seen by most telescopes.

“It is remarkable that we can detect planets orbiting unseen stars, but we’d really like to know something about the stars that these planets orbit,” explained Virginie Batista, leader of the Keck Observatory analysis.

“The Keck and Hubble telescopes allow us to detect these faint planetary host stars and determine their properties.” 

Oceanographers use backtracking models to trace MH370 wreckage's route

Modelling of the dispersal pattern of possible debris from missing Malaysia Airlines jet MH370. [Credit: University of Western Australia: Charitha Pattiaratchi and EMS Wijeratne]

Modelling of the dispersal pattern of possible debris from missing Malaysia Airlines jet MH370. [Credit: University of Western Australia: Charitha Pattiaratchi and EMS Wijeratne]

The University of WA oceanography department is using special reverse computer modelling to re-create the drift of wreckage found on Reunion Island to determine how it got to the remote Indian Ocean island.

A section of a wing from a Boeing 777 was found on the island and is presumed to be that of Malaysian Airlines flight MH370, which disappeared 16 months ago.

By analysing ocean currents, University of Western Australia Professor of coastal oceanography Charitha Pattiaratchi predicted more than a year ago that any debris from MH370 would come ashore in East Africa or nearby islands.

The anticlockwise Indian Ocean current flows up the Australian coast and west to Africa.

Professor Pattiaratchi told reporters that he expected the reverse modelling of the drift pattern of the wing part would confirm that search teams were looking in the right area — to the south-west of Perth.

3D-printed house assembled in just three hours

Chinese media are reporting that a 3D-printed house has been assembled in Xi’an, capital city of Shaanxi province, in just three hours.

Engineers on the project said the modules took about 10 days to print.

“It takes about half a year to build a traditional villa, but not to build a 3D house,” said An Yongliang, developing engineer of the company that designed and produced the house.

The house has six modules, with each weighing over 1000 kilograms. The costs of materials vary from 2,500 to 3,500 yuan (US$400-460) per square metre. print.

An said that the house is strong enough to survive a Magnitude 9 earthquake.