Hello again science fans,
안녕하세요 과학 팬 여러분, (Over 60,000 Bay Area residents speak Korean at home.)
BIOLOGY
Above is an artist’s representation of a flagellar motor that spins a bacterium’s flagella. The spinning flagella propel the bacterium through water. The colorful squiggly things represent proteins. The big wheel isn’t big. It would take 10 million of them side by side to span a single centimeter (0.4 inch). A typical rate of spin is 30,000 rpm, or 500 times a second. When you get the chance, come back here to watch this über-fascinating 23-minute video about this amazing bit of biomechanics.
A new study estimates that LUCA lived less than half a billion years after the formations of planet Earth. LUCA stands for Last Universal Common Ancestor. LUCA was a single solitary one-celled organism, and every living thing on our planet descended from it. ¿Every living thing? Yes. We are certain, because all living things share the same basic biochemistry: from the coding of specific peptides by triplets of nucleic acids in DNA to the use of adenosine triphosphate as a currency of energy. LUCA itself descended from other living organisms that must have differed in some aspects and biochemistries. But LUCA and its descendents were so successful that they likely drove all other versions of life to extinction.
Speaking of extinction, we are guilty as charged. We humans have always been suspected of driving over 30 genera of large mammals in the Americas to extinction after migrating here over 20,000 years ago. But doubts remained since the extinctions coincided with huge environmental changes as the Earth rebounded from the last glacial period. A new study incorporating AI data analyses concludes that humans were indeed chiefly responsible. Gone are the American mammoths, mastodons, camels, horses, glyptodonts, ground sloths, sabertooth cats, cheetahs, giant beavers, cave bears, ad nauseam. ¿What is a glyptodont? Apparently they were well worth eating.
Most of the mammals that lived during the reign of dinosaurs were small creatures, but not all. The recently described Patagomaia chainko was the size of a large fox and weighed about 14 kg.
CLIMATE
The Biden administration has approved over 9,000 drilling permits for oil and gas in its first three years; about the same as the previous Trump administration. The 2024 Republican Party Platform exclaims, “We will DRILL, BABY, DRILL and we … will harness that potential to power our future.” ¿Are there any bright spots for addressing climate change? Yes. Our school teachers are devoting more classroom time to recent global warming than before. The White House is working to modernize America’s energy grid to allow it to carry more clean energy and reduce planet-warming pollution. A Norse company is using the world’s first all-electric cargo ship to shuttle minerals to their processing plant. (It’s only about 25 km each way, but it’s a start.) The Lunaz company in Great Britain is converting garbage trucks from diesel-powered to all-electric.
MEDICINE / HEALTH
Prior to development of a vaccine in the 1980s, just about everyone contracted chickenpox, an affliction caused by the varicella zoster virus. Everyone – except the seriously immune compromised – recovered with un-fond memories of the dis-ease. But the viruses were not totally vanquished. They take up long-term residence inside of nerve cells. Decades later they painfully manifest themselves as ‘shingles’. Thankfully, i had a ‘Shingrix’ shot prior to the reëmergence of my population of varicella zoster virus, so my shingles symptoms were very mild. Odd discovery: the Shingrix vaccine delays the onset of dementia. It is possible that one cause of Alzheimer’s is our immune response to brain infections. Stay tuned!
A health tip: the use of hair relaxers is associated with the onset of breast and uterine cancers.
SPACE
The Perseid Meteor Shower is ongoing this week and will peak next Sunday night/Monday morning (11-12 August). My favorite location is Inspiration Point in the Berkeley hills. (Note: it gets crowded with delightful folk).
The Boeing Starliner crew, Sunita Williams and Butch Gilmore, have been busy helping the regular ISS crew with experiments and house cleaning. (“No. It’s YOUR turn to clean the zero-g toilets!”) NASA’s “return readiness review” has been postponed and the latest update is that “NASA is evaluating all options for the return of agency astronauts Butch Wilmore and Suni Williams.” Consider it an extended vacation with an unsurpassed view.
¿How many galaxies are in the observable universe? Estimates range from 100,000,000,000 to 2,000,000,000,000. Those are the galaxies we can see that have a million stars or more. Our observable universe is – at most – only 3% of the total universe. The total universe could, however, be infinite in expanse and hold an infinite number of galaxies. (My head hurts.)
FUN (?) NERDY VIDEOS
The Limelight – Show & Tell – Joe Schwarcz – 3 mins
Madagascar’s Tenrecs – Bizarre Beasts – Sarah Suta – 6 mins
Why Weeks are 7 Days – Star Talk – Neil deGrasse Tyson & Chuck Nice – 9 mins
Floods, Geography, & LIDAR – PBS Terra – Joe Hanson – 10 mins
U.S. Grid Battery Revolution – Just Have a Think – Dave Borlace – 11.5 mins
The Nancy Grace Roman Telescope – Dr. Becky – Becky Smethurst – 12 mins
Chaos & the Three Body Problem – Up & Atom – Jade Tan-Holmes – 14 mins
Dark Oxygen – Dr. Ben Miles – 15 mins
Euclid’s 5th Postulate & Non-Euclidean Geometry – Veritaseum – Derek Muller – 30 mins
Sea Change: The Gulf of Maine – PBS NOVA – 53 mins
Have a great week celebrating existence and practicing empathy,
Dave Almandsmith, Bay Area Skeptics
“For millions of years, mankind lived just like the animals. Then something happened which unleashed the power of our imagination. We learned to talk and we learned to listen. Speech has allowed the communication of ideas, enabling human beings to work together to build the impossible. Mankind’s greatest achievements have come about by talking, and its greatest failures by not talking.”
– Stephen Hawking (1942 – 2018) English theoretical physicist