2201
«Necktie knots are inherently topological structures; what makes them tractable is the particular manner in which they are constructed»
[T. Fink, Y. Mao, «Tie knots, random walks and topology»: buff.ly/3L85fKn]
2202
The southern cassowary has three-toed feet equipped with a lethal dagger-like claw up to 12 cm on the inner toe ow.ly/JusO30nm4e1. This photo by Sarah Davis shows a male southern cassowary's claws, possibly erasing any doubt that birds are dinosaurs buff.ly/2DCxsYg
2203
The Butterfly Mendocino Motor by Semyon Nazarov is the simplest version of this kind of motor with only two photovoltaic cells mounted with care to ensure precision balance. This motor will spin quietly to high RPMs on any sunlit windowsill [read more: buff.ly/3qGqGpJ]
2204
Psychotria elata is a tropical tree found in the rain forests of Central and South American countries. The plant has become internet-famous because of its flowers or rather the shape of the red bracts (modified leaves) before the flowers mature [source: buff.ly/2EIv5QY]
2205
An impressive eruption of the Volcán de Fuego, Guatemala, captured on August 27, 2022
[📹 Rob Brown: buff.ly/3xgyGUR]
2206
Sweden (like other countries) has long had a can & bottle deposit system giving people money back when they recycle—for aluminium cans, and since 1994 for plastic bottles. Each year Swedes recycle 1.8 billion bottles using the so-called pant system buff.ly/31oDdp6
2207
There's an amazing tabletop mountain in South America, with sheer 400 meter high cliffs on all sides: Mount Roraima [read more: bit.ly/2cf33mN]
2208
Mount Erebus is the second-highest volcano in Antarctica and the southernmost active volcano on Earth. This is what the ice towers that form around its steaming vents look like in a great picture by photographer George Steinmetz [read more: buff.ly/2ETU4RJ]
2209
A 2016 study found that sea turtles rest for ~11 hours per day, using just half the amount of oxygen that they use during foraging. Watch one taking a nap in this clip by Drew Sulock
[read more: buff.ly/3cCm6nV]
[video: buff.ly/3xdY24n]
2210
Saltwater Brewery is known for their beer, but also because of its development and widespread marketing of a biodegradable 6-pack ring that is edible to sea life [source, read more: buff.ly/2HleZlP]
2211
It has 600 million year of distance from us, three hearts, no bones, a beak with a venomous bite and a gut that runs though its brain and yet it can befriend a human teenager. Meet Laurel and her pet octopus Heidi [full video: buff.ly/2nfbc1t]
2212
Photographer Murat Öztürk captured this imrpressive scene containing an ant trying to take down a flying wasp buff.ly/2EL92ZW [the scene was not captured live and there's an article about the process used availble in Turkish, here: ow.ly/lwHc30nibJS]
2213
Induction hardening is a type of surface hardening in which a metal part is induction-heated and then quenched
[read more: buff.ly/2CtAXPl]
[source of the gif: buff.ly/3eqyDgz]
2214
It is generally thought that, in average, the largest amount that an ant could drink is about 35 μl. The clip also shows how ants need space to store water in their abdomen
[read more: buff.ly/31hEAIc]
[Ajith Subramanyan: buff.ly/3E5kDT7]
2215
Crops under solar panels can be a win-win, and in dry places, shade can reduce water use, increase CO₂ uptake and water-use efficiency; and crops are on average 30% bigger and healthier
[read more: buff.ly/2ZQCdW8]
[📹: buff.ly/3d8TSoP]
2216
Odd as it may seem, this occurred in 2020 in Ogre, Latvia and it's another example of how smart are corvids. This crow was literally explaining to a hedgehog that it had to cross the road
[read more: buff.ly/2SKBBQH]
[📹: buff.ly/3nJ5cbK]
twitter.com/cryptogemhodl/…
2217
A bicycle's performance is extraordinarily efficient
[read more: buff.ly/3RCD7RN]
[Chart from S. S. Wilson, Bicycle Technology, Scientific American, 1973: buff.ly/3Qv9tMV]
2218
«Science is more than a body of knowledge, it's a way of thinking»
— Carl Sagan
Last interview with Charlie Rose, May 27, 1996
[full interview: buff.ly/3BaU4f0]
2219
When first hatched, tawny frogmouth chicks have thick, white and fluffy plumage, weighing between 17-19 grams, looking like balls with a mouth
[source read more, Bonorong Wildlife Sanctuary: buff.ly/3xmjILB]
2220
NASA only uses 15 digits of π for calculating interplanetary travel. At 40 digits, you could calculate the circumference of a circle the size of the visible universe with an accuracy that'd fall off by less than the diameter of a single hydrogen atom ow.ly/rhmO30o4k7G
2221
These cups are made of linear mirrors with 24 sides: when put on the saucer the anamorphic design reveals a hidden image. Bonus: some of them also use a moiré effect, to give an even more impressive, animated result buff.ly/3RClrWt
2222
Located in Lishui, China, this water slide is 2723.08 m (8,933 ft 11 in) long with waterway winding its way down the side of Puhuasi Mountain and it's the record-breaking World [read more: buff.ly/3RBE6So-] twitter.com/AmazingPosts_/…
2223
This impressive tornado was filmed by Amie Kuxhaus in Martin, Soth Dakota on June 30, 2019
[read more: buff.ly/3d2T1Gi-]
2224
Have we ever seen the skin of a dinosaur? In some places, mummified dinosaurs' rests have been found and a process called permineralization (also responsible for the formation of petrified wood) preserved their skin too [source, read more: buff.ly/2EJveng]
2225
In the heart of this grove among the mountains of Mexico, half a billion Monarch butterflies lie sleeping. This spy hummingbird ventures to witness a breathtaking swarm
[📹 John Downer Productions: buff.ly/2VUVLbQ]
Astronomy, astronautics, meteorology, physics. Engineer, trying to build the big picture of #science via selected & curated pics, videos & links