sun

A three-minute minutephysics video on the orbital mechanics of why crashing into the Sun takes far more energy than leaving the solar system.

Kurzgesagt explains stellar engines such as the Shkadov thruster and Caplan thruster, which could move the Sun and solar system across the galaxy over millions of years to avoid hazards and reach new regions.

Veritasium shows what the world looks like through a UV camera. It covers how pigments absorb UV, how fluorescence works, and how UV imaging reveals sunscreen effectiveness and skin damage.

Technology Connections takes apart a 1940s Sunbeam Radiant Control toaster. It senses the toast's own browning and lowers and raises it automatically using purely mechanical parts and no electronics.

Ivor Cummins gives an 82-minute presentation on the history and science of vitamin D and human health. He draws on expert interviews to argue that sun exposure and vitamin D status are linked to many chronic diseases.

IEEE Spectrum interviews Samsung display researcher Johan Feenstra on how electrowetting displays work. He explains why they can match LCD capability while being about three times more efficient.

Potholer54 presents the climate science case and a market-oriented, conservative-friendly approach to addressing global warming, with sources listed. It is part one of a two-part series.

Engineering Explained works through whether electric cars are really worse for the environment than gasoline cars. It covers battery production emissions, the electricity mix used to charge, and how long an EV takes to break even on lifetime emissions.

Arthur Keller gives a roughly half-hour crash course on environmental collapse, covering exponential growth, carrying capacity and ecological overshoot.

Real Engineering examines whether greening the Sahara could draw down carbon and slow climate change. It concludes that the effort would be enormously costly and that changes in albedo and other effects undercut the climate benefit.

Numberphile with Simon Pampena on how humans misunderstand randomness, including coin-flip sequences, run lengths and the gambler's fallacy.

A Kurzgesagt animated explainer on how humanity could build a Dyson sphere, a swarm of structures capturing the sun's energy. It covers using Mercury's materials and a step-by-step construction approach.

Mathologer explains epicycles and complex Fourier series, inspired by an animation of Homer Simpson drawn with epicycles. It covers the shape of the Moon's orbit around the Sun and how to make your own epicycle drawings.