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Newton, Principia Mathematica - publicatie (1687)
2026-07-05
Philosophiae Naturalis Principia Mathematica (Lat.: “De wiskundige beginselen van de natuurfilosofie”, kortweg de Principia) is een werk van Isaac Newton gepubliceerd op 5 juli 1687.
Bekend is dat Newton het werk van ruim 500 pagina’s schreef tussen augustus 1684 en april 1686 (minder dan twee jaar dus) naar aanleiding van een bezoek dat Edmond Halley aan hem bracht. Het is echter zeer waarschijnlijk dat hij zijn ideeën erover al eerder ontwikkelde omdat hij tegenover Halley gewag maakte van zijn oplossing voor het probleem van de banen van de planeten (de reden voor Halley’s bezoek). Al in november 1684 zond hij hem en de Royal Society een uitgewerkte wiskundige beschrijving daarvan, onder de titel De motu corporum in gyrum (Over de beweging van lichamen in een baan), een artikel van negen pagina’s. Hierop liet Halley weten dat de Royal Society graag meer van zulk werk zou ontvangen, en het ook zou uitgeven. Volgens ooggetuigen werkte Newton vervolgens bijna dag en nacht aan het boek. Toen Newton de Principia afgerond had, had de Royal Society echter net haar hele budget gespendeerd aan de uitgave van De historia piscium, een boek over vissen, geschreven door Francis Willughby. Dat boek verkocht zeer slecht, en uiteindelijk financierde Edmond Halley de eerste druk van de Principia. Het werk is een van de invloedrijkste publicaties ooit verschenen in de exacte wetenschappen.
Links:
Philosophiæ naturalis principia mathematica

In de geschiedenis
2026-07-06, 2026-07-07, 2026-07-08, 2026-07-09, 2026-07-10, 2026-07-11, 2026-07-12, 2026-07-13 and 15 more dates
Links:
Wikipedia

Tuinvlindertelling 2026
2026-07-10 - 2026-07-12 | Nederland, Nederland
Welke soorten vlinders vliegen er in jouw tuin? Tel mee met de tuinvlindertelling en help de vlinders beter in kaart te brengen!
Loop tijdens de tellingdagen een rondje door de tuin en noteer gedurende 15 minuten alle vlinders die je ziet. Maar tel deze waarnemingen niet bij elkaar op, want dan kan het zijn dat je vlinders twee keer telt. Geef van elke vlindersoort het hoogste aantal door in het telformulier dat je tegelijk hebt gezien. Voorbeeld: je ziet eerst 3 dagpauwogen tegelijk. Tien minuten later zijn er weer 2 dagpauwogen. Dan geef je door: 3 dagpauwogen. Zie je later op de dag of één van de andere teldagen weer vlinders? Dan kun je die doorgeven via een nieuwe telling. Heb je een vlinder gezien die niet in de tellijst staat? Dat kan; we tellen alleen de meest voorkomende soorten tuinvlinders. Je hoeft deze waarneming dan niet in te vullen. Belangrijk: als je geen vlinders ziet is het ook belangrijk om dit door te geven. Deze data zijn net zo belangrijk als tellingen waar wel vlinders gezien zijn. Vul dan ‘0 dagvlinders gezien’ in in het telformulier.
Links:
Tuinvlindertelling

Space, mountains, oceans: Science at the frontiers of exploration (TV CERN webcast)
2026-07-11 16:00 - 23:00 (Europe/Amsterdam)
On Saturday 11 July 2026, join us at CERN Science Gateway from 16:00 onwards for an evening celebrating curiosity and discovery.
From space to oceans, to artificial intelligence, cosmic rays and the search for life in the Universe, “Future Explorers” will bring together scientists, engineers, astronauts, sailors, and artists to explore the frontiers of the unknown.
Links:
CERN

Citizen science platforms must mitigate against the threat of generative AI - publication
2026-07-13
In the commentary ‘Citizen science platforms must mitigate against the threat of generative AI’ in the science journal Nature, researchers warned that hundreds of fake images have already been discovered on popular databases for recording species, they said that the true scale of the issue is unknown – as many could go undetected – and could contaminate records collected by the public.
Links:
AI-altered images on birdwatching forums putting research at risk

Most Of The Universe Is Missing And We Don't Know Why (TV New Scientist webcast)
2026-07-17 17:00 - 20:00
Everything you see, touch and are built from is a minority of what the universe is actually made of, and the closer physics looks at the rest, the less the picture holds together.
In 3 hours, we move outwards through that problem: from the 85 per cent of matter that is invisible, to the visible matter whose textbook description is admittedly unfinished, to a dimension of space that scientists are now building by hand in a lab, and finally to the question of whether we can ever truly know what reality is made of at all.
Links:
What If Dark Energy Comes From Space-Time Itself?

The State of Food Security and Nutrition in the World 2026
2026-07-21
Global hunger declined for a third consecutive year in 2025, demonstrating that progress is possible. However, the improvements remain fragile, unevenly distributed and insufficient to achieve the Sustainable Development Goals by 2030, according to The State of Food Security and Nutrition in the World 2026 (SOFI 2026) report, released on Tuesday by five United Nations specialized agencies.
The report estimates that 7.8 percent of the global population faced hunger in 2025, down from 8.1 percent in 2024 and 8.6 percent in 2022, confirming a sustained, albeit slow, improvement. This means that around 645 million people were affected by hunger in 2025, representing a reduction of nearly 14 million compared to 2024 and 43 million compared to 2022. Despite global progress, recovery remains uneven across regions. Asia, together with Latin America and the Caribbean, has recorded steady improvements in recent years. In contrast, Africa is now home to approximately 309 million hungry people, compared with 292 million in Asia. Although Africa’s previously rising trend is beginning to stabilize, with the share of its population facing hunger decreasing from 20.3 percent in 2024 to 20.0 percent in 2025, the continent now has the highest number of hungry people in absolute terms amid a rapidly growing population. Broader measures of food access tell a similar story. In 2025, an estimated 25.8 percent of the global population (around 2.1 billion people) experienced moderate or severe food insecurity, meaning they were at times forced to compromise on the quality or quantity of the food they ate. This is down from 27.1 percent in 2024 and 28.7 percent in 2020 – equivalent to nearly 86 million fewer people than in 2024 and 135 million fewer than in 2020, though still above pre-pandemic levels. Regional disparities remain stark. More than half of Africa’s population (56.6 percent) faced moderate or severe food insecurity in 2025, compared to 20.3 percent in Asia, 22.9 percent in Latin America and the Caribbean, and 8.7 percent in Northern America and Europe. Food insecurity also continues to be more prevalent in rural areas than in peri-urban and urban areas, while women remain disproportionately affected, although the gender gap narrowed slightly in 2025.
Links:
The State of Food Security and Nutrition in the World 2026

Pi Approximation Day / Pi-benaderingsdag 2026
2026-07-22
Pi Approximation Day is observed every year on July 22 all around the world.
The fraction 22/7 is an approximate value of Pi, and there behind lays a specific reason why this day is observed on July 22. This day is celebrated on July 22 every year because the value of Pi is denoted by the fraction 22/7. Here, in the fraction 22/7 which denoted Pi, the numerator 22 symbolizes the date (22nd day of the month) and numerator 7 indicates the month (July). Approximations for the mathematical constant pi (π) in the history of mathematics reached an accuracy within 0.04% of the true value before the beginning of the Common Era. In Chinese mathematics, this was improved to approximations correct to what corresponds to about seven decimal digits by the 5th century. Further progress was not made until the 14th century, when Madhava of Sangamagrama developed approximations correct to eleven and then thirteen digits. Jamshīd al-Kāshī achieved sixteen digits next. Early modern mathematicians reached an accuracy of 35 digits by the beginning of the 17th century (Ludolph van Ceulen), and 126 digits by the 19th century (Jurij Vega), surpassing the accuracy required for any conceivable application outside of pure mathematics. The record of manual approximation of π is held by William Shanks, who calculated 527 decimals correctly in 1853. Since the middle of the 20th century, the approximation of π has been the task of electronic digital computers (for a comprehensive account, see Chronology of computation of π). On June 28, 2024, the current record was established by the StorageReview Lab team with Alexander Yee’s y-cruncher with 202 trillion (2.02×1014) digits.
Links:
Pi Approximation Day History, Meaning, Significance, other Celebration ideas
