A Chalk Walk

Among scientists, a “chalk talk” means a lecture without a laptop and beamer to display fancy graphics, but simply using a blackboard and a piece of chalk to draw diagrams and formulas while you speak. It’s sort of[…]

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Lunar Eclipse over Amsterdam

Last night there was a (complete) lunar eclipse which was visible from Amsterdam. Many thanks to Jo & Piet for sharing their 9th-floor apartment balcony with me, from where the views were just wonderful! Here are some impressions.[…]

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Citizen Science: Schumann Resonances

Schumann resonances (SR) are global electromagnetic resonances generated by lightning in the cavity between the Earth’s surface and the ionosphere. Their existence was predicted mathematically in 1952. However, it took another decade before they could be reliably measured[…]

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