Below are the Twitter #weirdscifacts for the previous week!

326. Feb 02: Daguerre’s photographic process was made “free to the world” in 1839 — w/ exception of Great Britain. Daguerre was competing with British scientist Talbot to perfect the photographic process, and he ended up patenting his invention in England to prevent being “scooped”.  A week later, France (which had then acquired the rights from Daguerre) declared it a process “free to the world”, which by law excluded England!  This unfortunate outcome is said to have hindered British photography research for years.

327. Feb 03: Neutron star density: a sugar cube-sized piece would roughly have mass of entire human population. We all learn in grade school that atoms are mostly “empty space”; this leaves a lot of room for them to be compressed.  When a relatively light mass star runs out of fuel and collapses under its own gravitational “weight”, becoming a tightly-packed aggregate of electrons, protons and neutrons known as a white dwarf.  A star of larger mass possesses larger gravitational “weight”, and can squeeze the electrons and protons together to form neutrons, leaving an even denser object known as a neutron star.  As this fact demonstrates, such objects are incredibly dense: with a mass between 1.35 and 2.0 solar masses, a neutron star might have a radius of only 12 km!

328. Feb 04: The Bay of Fundy has a tidal range (difference in high/low tide) of 55 feet. If it isn’t clear, this means that the difference in water elevation between high and low tide is some 55 feet — perhaps the height of a four-story building!  This is the largest tidal range in the world, statistically tied with Ungava Bay.

329. Feb 05: A classic: Mercury is a liquid so dense that cannonballs will float in it. This can be understood by Archimedes’ principle: “Any object, wholly or partially immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object.”  Mercury has a room temperature density of 13.53 g/cm³, while solid iron has a density of 7.87 g/cm³.  Since Mercury has almost twice the density of iron, the iron will float at a level halfway submerged, as seen in the video.  Mercury is even denser than lead: 11.34 g/cm³.

330. Feb 06: The Casimir effect: in which quantum fluctuations in vacuum exert a pressure! In our current understanding of quantum physics, even empty space is never truly empty: so-called “virtual particles”, pairs of particles and anti-particles, constantly wink into and out of existence, unobserved.  Even though they are unobserved, however, their effects can be felt.  When two metal plates are brought close together, the area between them has the creation of these virtual particles hindered.  Because more virtual particles are created outside the plates, a net pressure is created that pushes the plates together.

331. Feb 07: The fungus that turns carpenter ants into zombies…

332. Feb 08: The odd case of Phineas Gage, who survived an iron rod passing through his head. Gage may not even have lost consciousness when the 1.25” iron rod went through his skull and brain!  The case revised doctor’s views of traumatic brain injuries and provided some of the first insights into behavioral changes brought about by such injuries.  (Link to a classic @scicurious post.)