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A short history of robots


Hank Green, from SciShow, presents a short history of robots, from the industrial robots to the humanoid robots we have today. DARPA is hosting a robot contest in this summer and humanoid robots will fight each other to win the trophy the best human robots ever.

Also, see some humanoid robots running:

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science

The Moon: is has a tail and we would have a catastrophic planet without it


The Moon has a tail made up of sodium atoms very thinly dispersed throughout the small Moon exosphere. Moons atmosphere, called exosphere, is so rare that when it is full Moon and it is between us and the Sun, its atmosphere gets pushed around towards the Earth. This way we will be able to reside inside Moon’s tail.

You can read more here.

Also, without the Moon we would have a day that would be only 6-8 hours and the axial tilt would be much greater:

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science

Lakes that explode? Almost: they erupt


Lake Nyos, from Cameroun, released 80 million cubic meters of carbon dioxide gas in its surroundings with a speed of 50 kmph and suffocating everything within a 25 km radius. That is tough.

Since then the researchers have found several such lakes that erupt and all of them are in Africa. These lake eruptions are called limnic eruptions and they are deadly. Now the researchers have measurement devices all over lakes Nyos and Manoon and they also have built pipes to let that carbon dioxide get out and not bursts whenever it pleases to.

Lake Kivu, on the border of Rwanda and Congo seems to have the same accumulation of gases issue. Kivu has also pockets of methane in its belly and right now some of that methane is used to power some of the homes of the 2 million people living on its shores.

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geek science

5 most dangerous chemicals on Earth


Hank Green, from SciShow, presents a list of top 5 dangerous chemicals int he world. Some of these were so dangerous that not even the nazis would dare touch or use them.

What 5 chemicals is it about then? Here they are:
1. ClF3, chlorine trifluoride, also called “substance N” by the nazis – blows up when exposed to air, lethal when inhaled, burns at 2400 degrees Celsius. It can burn bricks or asbestos or concrete and 1 meter or dirt beneath that too. It is a better oxidizer than oxygen.

2. C2N14, azidoazide azide – the most explosive chemical compound ever created. It explodes even when left alone. The researchers left azidoazide azide in a dark room undisturbed and it still exploded.

3. Ch3CdCh3, dimethylcadmium – the most toxic chemical in the world. A few micrograms/cubic meter are enough to kill you. Friction, water, and any movement will make it explode.

4. C3H6S, thioacetone – the worlds smelliest chemical. You can smell a drop of thioacetone from half a kilometer away. In 1989 the whole city of Freiburg was evacuated due to the accidental release of this substance at a factory in that city.

5. H2FsbF6, fluoroantimonic acid – the strongest corrosive agent in the world and the most dangerous acid ever invented. It is 10 million billions times stronger than sulfuric acid. You can only store fluoroantimonic acid in teflon containers because teflon contains bonds of C-F, carbon-fluorine, the strongest bond in the organic chemistry chemical. It eats glass like it is being nothing.

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Motor proteins, the things that make the cell work and divide

The motor proteins are proteins from within our cells that have the role of carrying cellular material around the cell (food, signaling molecules, genetic information). It uses the cells highway system called microtubule cytoskeleton created from a protein called tubulin. This cytoskelton gives the cells their structure.

One of the motor proteins Hank Green speaks about in this video is kinesin which has a head that can hold cargo, a middle area and two feet that can literally walk around on the tubes of the cytoskeleton.

Each motor protein’s foot uses ATP, adenosine triphosphate, a molecule that floats in the cell. When one foot grabs a molecule of ATP it changes shape and then it swings forward. A motor protein can travel with a speed of 1 micrometer/second.

This speed is too small for the nerve cell from our foot, which has a length of about 1 meter, but luckily the motor proteins can travel down this length even in 1-2 hours.

But how to motor proteins help cells divide? They simply job in one place until the microtubules from the cytoskeleton roll along and then break.

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geek learn science

SciShow: what is energy?


Energy can be found everywhere and in many forms. In the same way as the existence of matter, energy as existed since the dawn of the Universe. It is a constant quantity in the Universe: nothing gets lost, but only transformed.

Energy is the ability to do work and mass and energy are the same thing. Remember E=mc^2? Energy can never be created, but only transferred. Also, it seems that we are 98% energy. Veritasium created a great video about mass that really needs to be watched: if mass is energy, it means that the trees are full of energy?

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Estivation, much like the hybernation, but for hot times and areas


Estivation is a process in which animals retain water and slow down metabolism in order to survive a hot dry season. Most of the animals that undergo estivation will cover themselves with a mucus that will keep them protected from warmth like a cocoon.

Estivation can last from weeks, months to sometimes years in Australia where some frogs retain water for up to two years and bury themselves 1 meter int he sand.

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geek learn science

Venus, not the best place for your holydays


Hank Green, from SciShow, explains why Venus is NOT Earth’s twin and why is it dangerous to live in there. In any case, you won’t be able to live in there not for even one second. The probes that landed there in the 70s and 80s coudl not even last for more than 50 minutes due to the temperatures above 480 degrees Celsius.

Also, the atmospheric pressure is 90 times than that of Earths. We would be crushed in an instant. More than 95% of the air from there is CO2 and it rains sulfuric acid. Just great for a trip to Hell. Not recommended.

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What really killed the dinosaurs? It wasn’t the asteroid


Hank Green, from SciShow, explains how researchers got the idea that an asteroid killed the dinosaurs 65 million years ago and why that is not the whole picture. It seems that the asteroid was the last drop in the bucket and that climate change, volcanic eruptions were the ones that started the extinction.

The asteroid came to finish a job that was already started by Earth changes. While the asteroid theory seems compelling we need to look at the bigger picture. Could we survive should such an asteroid hit Earth again? Some of us yes as we have the tech to live underground for many years, but it would be a big cost for humanity.

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Learn all there is to know about Ebola from Scishow


Hank Green, from SciShow, explains what Ebola is, and where is it coming from. It is not contagious as, let’s say, the flu, but it is nonetheless a deadly disease that can kill 90% of the infected victims. Ebola is transmitted to other hosts via direct contact (of your mouth, eyes, or open wound) with bodily fluids from the patients: vomit, urine, fecal matter, semen, blood. It transmits much like Hepatitis B.

So, in case you get near a guy with Ebola make sure to not touch anything they touched and stand at a certain distance. You’ll be safe. I wrote about Ebola before in this blog post. Even if it so deadly, if the patients are quarantined, the there is no such a big deal.