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A pulsing black hole in the centre of a distant galaxy sheds light on black hole and galaxy formation. How fast are black holes rotating and how does that rotation change over its life-span?
Droplets levitate on a bath of liquid nitrogen and are spontaneously self-propelled.
Do negative air ions improve mood, anxiety, depression, alertness?
A bisected grape in the microwave makes plasma. But how does it work? A grape is the right size and refractive index to trap microwaves inside it. When you place two (or two halves) close together the fields interact with each other creating a maximum of electromagnetic energy where they touch. This creates heating, sparks, and plasma, which is further fed with energy directly by the microwaves.
Is it possible to reconstruct sound from high-speed video images?
Compliant mechanisms have lots of advantages over traditional devices. SimpliSafe is awesome security. It's really effective, easy to use, and the price is great.
Research has found human brains can pick up on rotations of geomagnetic-strength fields as evidenced by drops in alpha wave power following stimulus.
I always wanted to know why film looked better than video. Moving electronic images have as long a history but were invented for a different purpose.
We are about to see the first image of a black hole, the supermassive black hole Sagittarius A* at the center of the Milky Way galaxy. But what is that image really showing us?
The Event Horizon Telescope Collaboration observed the supermassive black holes at the center of M87 and our Milky Way galaxy (SgrA*) finding the dark central shadow in accordance with General Relativity, further demonstrating the power of this 100 year-old theory.
The story of three impressive high school science projects. Can you guess which student won $250,000 in the #RegeneronSTS?
Tiny robots activated by magnetic fields may be used in future biomedical procedures.
I took a boat through 96 million black plastic balls on the Los Angeles reservoir to find out why they're there. The first time I heard about shade balls the claim was they reduce evaporation. But it turns out this isn't the reason they were introduced.
My hypothesis is that the algorithm, rather than viewer preference, drives views on the site. As the algorithm shifts, various YouTubers experience burnout (as what used to work no longer works) and right now click-through rate is the key metric. So clickable titles and thumbnails are the only way to get a lot of impressions and hence views - they are the only way to go viral. This leads me to wonder which audiences will become most prevalent on the site and if there will even be a place for educational content. In the long-term, hopefully YouTube is able to measure satisfaction through surveys and other metrics to ensure an optimal experience for everyone on the site.
Aerogels are the world's lightest (least dense) solids. They are also excellent thermal insulators and have been used in numerous Mars missions and the Stardust comet particle-return mission. The focus of this video is silica aerogels, though graphene aerogels are now technically the lightest.
I bought 10,000 shade balls and tried to swim in them. They appear to act like a non-Newtonian fluid: rigid under high shear stress, but they flow like a liquid under low shear.
Aerogel has extraordinary properties but it can be tough to work with. This video looks at modifying aerogels to take advantage of their unique characteristics.
The Vikings suffered many hardships living in the north of Europe: long, cold winters and importantly a lack of sunlight. Luckily, they had cod.
Apollo astronauts trained in nuclear bomb craters at the Nevada National Security Site. But why?
Electric cars are now ready to take over thanks to advances in battery technology and their inherent benefits: torque, handling, maintenance.
The Mars Helicopter aims to make the first powered flight on another planet when it takes off on Mars as part of the Mars 2020 mission. I learned a lot getting to visit the drone right before it was mounted on the rover.
I used a nitrogen membrane and Stirling cryocooler to liquefy nitrogen out of the air.
We put aerogel to the test vs 'not-a-flamethrower', a huge 2000°C flame to a large fiberglass blanket infused with silica aerogel - formerly the lightest solid (that title is now held by graphene aerogel).
A planet has been predicted to orbit the sun with a period of 10,000 years, a mass 5x that of Earth on a highly elliptical and inclined orbit. What evidence supports the existence of such a strange object at the edge of our solar system?
Spinning objects have strange instabilities known as The Dzhanibekov Effect or Tennis Racket Theorem - this video offers an intuitive explanation.
On first glance it's surprising that origami -- a centuries old art of folding paper to achieve particular aesthetics -- is applicable to engineering. But upon closer consideration there are a lot of reasons methods developed for paper folding are also applicable to engineering: origami allows you to take a flat sheet of material and convert it to almost any shape only by folding. Plus for large flat structures, origami provides a way of shrinking dimensions while ensuring simply deployment - this is particularly useful for solar arrays in space applications. Furthermore, motions designed to take advantage of the flexibility of paper can also be used to form compliant mechanisms for engineering like the kaleidocycle. Since the principles of origami are scalable, mechanisms can also be dramatically miniaturized.
Huge thanks to all the YouTubers who organized this. My apologies for the repost.
These videos are from 2012 so my interest in trees goes back a long ways. I think these videos discuss two of the most interesting and amazing facts about our leafy friends: they are made mostly of CO2 (which comes from us breathing out amongst other sources) and they can transport water up a tube higher than any we can currently manufacture. So trees are out to get you. But we do much worse to them so we owe it to them to plant some more. 20 mil is a good start.
Why does shaken soda explode? Does ice melt first in fresh or salt water?
Chaos theory means deterministic systems can be unpredictable.
Scientists like Prof Sinclair have evidence of speeding up, slowing, and even reversing aging.
Common pitfalls of New Year's resolutions and how I plan to avoid them.
