Science news digest – 27th November 2012
In the science news this week, astronomers unlock the secrets of a dwarf planet, Makemake, for the first time, intelligent mannequins that watch you while you shop, worrying signs of ocean acidification in the Southern Ocean, and finally… the island that never was.
Analysis reveals dwarf planet’s secrets
Astronomers have been able to properly study the dwarf planet, Makemake for the first time after it passed in front of the light from a distant star.
Makemake is one of the five dwarf planets found in our Solar System, a list that includes Pluto, which was famously demoted to dwarf planet status in 2006.
The observations of Makemake were carried out in April 2011, when the dwarf planet passed in front of the light from a distant star. All in all, it blocked out the star for about a minute, but it was enough to time for astronomers to discover the dwarf’s size, atmosphere, and density.
The team of astronomers were led by Jose Luis Ortiz from the Andalucian Institute of Astrophysics in Spain, and the study involved seven telescopes situated across Brazil and Chile, reported the BBC.
The size of the dwarf was estimated to be about two-thirds that of Pluto, and this was confirmed by the observation. It was also discovered that Makemake is not quite spherical, measuring 1,430km across in one direction, and 1,500km across the other.
They have estimated the density to be about 1.7 grams per cubic centimetre – similar to that of Pluto, but still less than a third than that of the Earth.
However, most surprisingly, it was found that the dwarf planet has practically no atmosphere at all, explained Dr Ortiz.
"As Makemake passed in front of the star and blocked it out, the star disappeared and reappeared very abruptly, rather than fading and brightening gradually," said Dr Ortiz.
"This means that the little dwarf planet has no significant atmosphere. It was thought that Makemake had a good chance of having developed an atmosphere - that it has no sign of one at all shows just how much we have yet to learn about these mysterious bodies.
"Finding out about Makemake's properties for the first time is a big step forward in our study of the select club of icy dwarf planets."
Market research taken to new levels with intelligent mannequins
An Italian company have fitted shop floor mannequins with facial recognition software that can track the age, sex and race of the customers walking around the shop, reported Wired.
The £3,236 ($4,000) EyeSee mannequins use the same software normally used in high security locations, such as airports, but the shop floor mannequins are being used for marketing purposes rather than security ones. The aim is to improve the layout, branding and marketing within the store based on the shopping habits of their customers.
"It's a system that's able to give demographics about the person passing in front of it," said Max Catanese, the CEO of the company producing the mannequins. "It's based on an algorithm. The algorithm analysed three million faces before going to production and now the number, as well as the accuracy, is rising. Once [companies] read the data, they can implement strategies inside the stores to boost sales."
The technology has already been installed in the stores of five global brands across four countries, including two in Europe, the US and Canada.
The companies piloting the system have already seen an increase in sales. In one store, for example, the system noticed a peak in the number of Asian customers using a particular entrance every day at 5pm. The manager then decided to place two Asian sales assistants by that entrance at that time, and lo and behold, the store saw a 12 per cent increase in sales that day, and a 22 per cent increase in the following days.
Animals under threat by ocean acidification
In a small patch of the Southern Ocean, the shells of sea snails are already starting to dissolve – the first piece of evidence to indicate marine life is being affected as a result of man-made ocean acidification, reported New Scientist.
Geraint Tarling and his colleagues, from the British Antarctic Survey in Cambridge, captured free-swimming sea snails called pteropods in early 2008 from an area in the Southern Ocean. Using an electron microscope, they found that the outer layers of the hard shells of the snails showed signs of unusual corrosion.
Ocean acidification is caused by the additional carbon dioxide in the atmosphere as a result of human activity. The CO2 dissolves in water forming carbonic acid, which changes the pH of sea water, making it less alkaline. This affects organisms that have hard shells, such as corals and molluscs.
These organisms use calcium carbonate from the water to build their shells, but with more carbonic acid in the water, this means there are more hydrogen ions, which react with the carbonate ions, making them unavailable to form calcium carbonate.
The most vulnerable animals are those, like pteropods, that build their shells entirely from a form of calcium carbonate, called aragonite, which is extremely sensitive to increased acidity.
The area where the problems have already become noticeable is a part of the Southern Ocean where deep water is brought up to the surface, which is naturally low in aragonite anyway, but not usually enough to cause a problem.
The island that never was
For more than a decade, Sandy Island has been visible on the world’s maps as a small island in the Coral Sea off Australia - part of the vast Pacific Ocean. So it was somewhat surprising when marine scientists arrived at the island to discover it didn’t exist, reported the Guardian.
The Australian scientists, led by Maria Seaton at Sydney University, set off on a voyage to study plate tectonics. Realising the island lay on their planned route, the scientists decided to visit it, having realised although the island showed up on the Google Earth map, there were no images of it. Equally mysterious, the island featured on the usually reliable world coastline database, but there was no sign of it on their sea chart.
Dr Steven Micklethwaite, a crew member from the University of Western Australia, recalled: "We went upstairs to the bridge and found that the navigation charts the ship uses didn't have it.
"And so at that point we thought: Well, who do we trust? Do we trust Google Earth or do we trust the navigation charts? "
The scientist added: "This was one of those intriguing questions. It wasn't far outside of our path. We decided to actually sail through the island ... Lo and behold there was nothing! The ocean floor didn't ever get shallower than 1300 metres below the wave-base. There's an island in the middle of nowhere that doesn't actually exist."
Danny Dorling, president of the British Society of Cartographers, was not surprised that an error like this had occured. "You can't create a perfect map. You never will," he said. "Our current world map is a collection of highly accurate satellite maps and some of the oldest data collected from Admiralty charts."
The mistake would have been surprising if the location had been a busy shipping lane or populated area, Dorling said. "The Coral Sea is in the middle of nowhere."