Ahad, 17 September 2017

Do You Need To Shock Your Hand With An Electric Eel To Be a Scientist?

Electric eel is actually a fish.

Not necessarily you need too, but once someone did it, many others will follow. At least one of the researchers Kenneth Catania of Vanderbilt University, a professor of biological science already did to complete his paper, "Power Transfer to a Human during an Electric Eel's Shocking Leap."

Even though the electric eel potentially producing high voltage of electric potential, the current amount still unable to kill bigger animals (including human), anyway this electrical shock enough to make any potential predator runs away.


The electric eel behavior during an attack.

The setup during the experiment by Professor Catania.

The close up of electric eel.

Electric eel is not the only creatures that can produce electricity. One more example of electricity producing fish is electric rays from the order Torpediniformes. In fact these electric rays had been used by Greek for patient during childbirth and operation.

While the experiment by Catania provide an evident of how the electric eel shock works on their predator with its shocking leap. Plus the measurement also provide more details of current flows during the attack.


With the experiments Catania was able to describe many details related to the electric’s eel electric shocking mysteries. Perhaps he also inspires many others to try the experience in the future.







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Sabtu, 16 September 2017

Giant Flying Bird Not Just a Myth

Haast's eagle try to capture it's prey the moa.

Legend about huge flying bird from native stories not just a myth. Few species of giant flying birds did exist not long ago. Even though they were not killed directly by men, but fighting with men over the same food source can be a bad thing too.

Haast’s eagle (Harpagornis moorei) is another giant birds that just extinct few hundred years ago from its native area, New Zealand. This giant bird has remained as a legend for Pouakai and Maori people until the truth was discovered.

The restoration of the skull.


Haast’s eagle became extinct around 1400 AD when their primary food resources had been hunted by the first Māori that came to the South Island of New Zealand. Compared to men that can easily change their food source, the Haast’s eagle had vanished together like their prey the moa.

The size of Haast’s eagle was even larger than the largest living vultures so it also the largest known true raptors. With the size of females were significantly larger than males, the weight of females were estimates to be in the range of 10–15 kg (22–33 lb) and males around 9–12 kg (20–26 lb).


The different in size between the size of Haast's eagle and its closest living relative, the little eagle.

The model of Haast's eagle attacking a moa at Te Papa. 

The main food sourced for the Haast’s eagle was the large flightless bird species known as moa, with body weight can reach up to fifteen times the weight of itself. The eagle was able to kill the giant bird by swooping it at the speeds up to 80 km/h (50 mph).







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Isnin, 11 September 2017

The Cave of the Crystal Giants


It's hard to believe the picture if you never heard about the Cave of the Crystals or Giant Crystal Cave (Spanish: Cueva de los Cristales) located in Naica, Chihuahua, Mexico. The cave was discovered by miners excavating for new tunnel for mining company Industrias Peñoles in April 2000 while drilling through Naica fault at the depth of 300 meters (980 ft). The cave was discovered by the brothers Eloy and Javier Delgado.

The crystals formed in the cave known as selenite crystals (gypsum, CaSO4·2 H2O), some of the largest natural crystal ever found. The largest crystals so far is 12 m (39 ft) in length, 4 m (13 ft) in diameter and 55 tons in weight. The minerals crystallized at very slow rate over the course of at least 500,000 years to form the crystals found today.



In 1910 miners discovered another cave that was known as Cave of Swords (Spanish: Cueva de las Espadas). This cave is located at the depth of 120 meters (390 ft) above the Cave of Crystals. It also contains crystals formation with 1 m (3 ft 3 in) long crystals.

The cave will never be open to public since the condition inside the cave are not suitable for human. The temperature can reach up to 58 °C (136 °F) with 90 to 99 percent of humidity. Exploration to the cave requires special suites. The geologists ever visited into the cave worn a special designed suits, strewn with ice packs. Without a proper suit, human can only endure approximately 10 minutes of exposure to the condition.



To know more about the cave you also can watch Discovery Channel program Naica: Beyond The Crystals Cave in 2011 production.

The cave was reported to be re-flooded by Penelope Boston in February 2017 to the BBC for the mining operations had been ceased.


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Ahad, 10 September 2017

Blood Not Always Red!



We and many other animals share the same colour of the blood that is red. Anyway there are many other creatures living on earth with different colours of blood. Here we are going to find out what color and why they are coloured so.

Red blood caused by the protein known as haemoglobin. Iron atom in this molecule bind to the oxygen we breathe in order carry it to other parts of the body. The reaction changes haemoglobin's structure so it absorbs and reflects light differently; that's the reason why the oxygenated blood appears red while deoxygenated blood is darker.


While the green blood belong to some marine worms and leeches. They have molecule called chlorocruorin in their blood. The protein have similar structure to haemoglobin, anyway it make their blood green instead of red. There are also animals with blood contains both chlorocruorin and haemoglobin, and it makes their blood color closer to red. So the green blood are not belong to alien out of the space!


There are also creatures with blue blood such octopuses, squid, spiders and some other molluscs. The blue color produced by protein called haemocyanin. Haemocyanin flows freely in the vessels, and contains copper atoms rather than iron. It might appear blue when oxygenated, it is actually colourless when deoxygenated.


When those colours might be in your imagination but not this one, 'purple'. Purple blood colours belong to some species of marine worms and brachiopods. This colour contribute by the protein called haemerythrin. Similar to haemocyanin, haemerythrin is colourless in deoxygenated. While this protein contains iron atoms, compared to haemoglobin it isn't suited to binding with oxygen molecules.

So that's it. There are many other colours of blood that we can include in the next horror movies. 


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Ahad, 3 September 2017

Mechanical Calculator Another Marvelous Invention

Curta mechanical calculator, one of the marvelous mechanical calculators ever invented.

Why we need to take a look at mechanical calculator when today the digital calculator can works better? Well, the invention of mechanical calculator itself is the result of complicated calculation and mechanical precision, so you can think how useful it was before the digital edge.

Before we go to more complicated mechanical calculator we might want to know more about the simple calculation apparatus such as abacus that had been used in ancient China. This device has been used until today in order to teach kid to know the concept of additional and subtraction.

The advancement of mathematical knowledge requires human to do more repetitive calculation, in large numbers and more complicated task. To safe time on calculations instead of the ideas itself such as in astrology and geometries, the calculation apparatus are very important.

The Napier's bones.

Page from a 1619 book of mathematical tables by Matthias Bernegger, showing values for the sine, tangent and secant trigonometric functions.

A typical ten-inch student slide rule.

There were many types of mechanical calculation apparatus since ancient times. Some of them showing of the result of the calculation rather than input numbers such as the Antikythera mechanism or simplification such as for the astrolabes.

Back to mechanical calculator machine that use specifically to calculate numbers, few of them being invented since as early as 17th century. One of the best inventions was Pascal's calculator, invented by Blaise Pascal in 1642. On the same century there were few other tools invented like Napier's bones, logarithmic tables and the slide rule. We are all wondering what are those things are!

In 18th century more complicated mechanical calculator was invented by Giovanni Poleni in 1709. In fact there were many others trying to invent calculation machines such as German Johann Helfrich Müller, French Lépine, German Antonius Braun, French Hillerin de Boistissandeau, German Philipp Matthäus Hahn, and English Lord Stanhope. Maybe there were few others that not documented.

Perhaps the best mechanical calculator ever invented was "Difference Engine No. 1," the invention of Charles Babbage in 1822. The machine has more capabilities of calculating up to seven numbers up to 31 decimal digits each. It also the first calculating machine that comes with printer. The project was abandoned in 1842. Anyway the working replica was built in 2005 by London’s Science Museum.


The working difference engine, built a century and a half based on Charles Babbage's design on display at London Science Museum.

Four of Pascal's calculators and one machine built by Lépine in 1725, display at Musée des Arts et Métiers.
Curta Type I, on display at the Musée des Arts et Métiers, Paris.


Yes, there were many other working mechanical calculators invented before the digital edge provides us with cheaper pocket calculator. The pocket version of mechanical calculator knows as Curta was invented by Curt Herzstark in the 1930s in Vienna, Austria. Until today this mechanical calculator still become one of the favorite for mechanical calculator’s fan to be part of their collection. Some fan even rebuilt this calculator using 3D printer such as the one bought by Adam Savage in his video and we all so envy with it.






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