"KM3NeT is a research infrastructure housing the next generation neutrino telescopes. Once completed, the telescopes will have detector volumes between megaton and several cubic kilometres of clear sea water. Located in the deepest seas of the Mediterranean, KM3NeT will open a new window on our Universe, but also contribute to the research of the properties of the elusive neutrino particles. With the ARCA telescope, KM3NeT scientists will search for neutrinos from distant astrophysical sources such as supernovae, gamma ray bursters or colliding stars. The ORCA telescope is the instrument for KM3NeT scientists studying neutrino properties exploiting neutrinos generated in the Earth's atmosphere. Arrays of thousands of optical sensors will detect the faint light in the deep sea from charged particles originating from collisions of the neutrinos and the Earth. The facility will also house instrumentation for Earth and Sea sciences for long-term and on-line monitoring of the deep sea environment and the sea bottom at depth of several kilometers."
See https://www.km3net.org/km3net-detects-the-highest-energy-neutrino-ever-observed/ for a recent observation.
Found via https://xkcd.com/3053

Found on Ryan Barrett's blog https://snarfed.org/2025-01-29_54565

The apparent contradiction between quantum mechanics, where the von Neumann entropy stays constant and the second law of thermodynamics can be resolved by using Shannon entropy.
F. Meier et al., Emergence of a Second Law of Thermodynamics in Isolated Quantum Systems, PRX Quantum 6, 010309 (2025). https://doi.org/10.1103/PRXQuantum.6.010309

Includes US patent 2,883,619 Electrical Probe by John R. Kobbe and William J. Polits awarded on April 21, 1959 for use of a resistive center conductor.
The site was found via a link on the Tektronix wiki https://w140.com/tekwiki/wiki/Risetime_Calculator

Works only for places in Germany. See https://forecast.solar/ for a potential alternative.

Project using the camera of Android or iOS phones to detect cosmic rays.

The General Mission Analysis Tool (GMAT) is the world's only enterprise, multi-mission, open source software system for space mission design, optimization, and navigation. The system supports missions in flight regimes ranging from low Earth orbit to lunar, libration point, and deep space missions. GMAT is developed by a team of NASA, private industry, public, and private contributors and is used for real-world mission support, engineering studies, as a tool for education, and public engagement.

Experiments tracking DCF77 and MSF, using amplitude, phase and correlation to measure time with respect to GPS.

Found via https://www.meteornews.net/2022/10/26/uk-radio-meteor-beacon-project and https://www.raspberrypi.com/news/meteor-beacon-for-astronomy/

The General Mission Analysis Tool (GMAT) is an open-source space mission analysis tool. Found via https://destevez.net/2022/09/more-qo-100-orbit-determination/