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This is an ongoing list of fairly recent scientific discoveries, findings, theories, and observations that I've heard or read about lately. Areas of study most likely to be represented include astronomy, cosmology, astrophysics, quantum physics, complex systems, computer science, maybe a little biology, paleontology.... and if you don't see it, just ask!
"Vodka factory in space." Twenty five years ago, astronomers thought the interstellar medium within our galaxy consisted of single atoms. But using radio telescopes and detectors sensitive to radiation emitted by molecules, "they found that 10 to 50 percent of the gas in our galaxy is molecular -- atoms stuck together -- and that it tends to cluster in giant clouds. About 99 percent of this gas is molecular hydrogen... but at least 53 other molecules have been detected, including ethyl alcohol, or vodka. The clouds of gas near the center of our galaxy contain enough vodka to fill more than 10,000 goblets the size of earth." [Heinz Pagels, Perfect Symmetry]
"Tree stem diameters fluctuate with tides." This was the title of a bit of scientific correspondence from Zurcher and Cantiani in the April 16, 1998 issue of Nature. They said "The diameter of tree stems... undergoes rhythmic fluctuations. We find a strong correlation between these fluctuations and the timing and strength of tides. This correlation suggests that the Moon is influencing the flow of water between different parts of the trees."
June 5, 1998: A collaboration of scientists announced they found evidence that NEUTRINOS HAVE MASS. In the physics world, this is big-time stuff with potentially significant consequences on prevailing theories. One writer went so far as to say,
"These new results could prove to be a key to finding the holy grail of physics, the unified theory, and work towards understanding of the origins of the matter from which we are made and the ultimate fate of the universe."Of course, neutrinos were always suspected to have a small mass. Cosmologists always hoped the neutrino had a small mass so as to help "close" the Universe and explain what's keeping galactic clusters as well as galaxies themselves from flying apart. But the mass reportedly found for the muon neutrino -- .07 plus or minus .04 electronVolts -- is about 100 times smaller than any estimate I've ever heard for a possible mass, and according to the book I happen to be reading, a neutrino mass lower than a few eV ceases to be "cosmologically interesting." The comments from the physics pros at Dr. Neutrino's website are rather derogatory and disbelieving of this finding! :-) This is understandable since at least two such neutrino-mass claims have been made before -- as far back as the early '80s. These were later contradicted.
The huge gamma ray burst (GRB) of December 14, 1997, was quite a headline grabber. Some papers reported that this single, short-period burst released as much energy as all the stars in the entire Universe. Understandably, they're now calling it a hyperburst. There were three articles in the May 7, 1998 journal Nature about this event. (That's when the headlines occurred.) The extremely high estimates of energy output are in major part derived from the association of the GRB with a host galaxy at the very high redshift of z = 3.42, an area of the Universe about 10 billion lightyears distant which shows us a time when the Universe was only about 10% its present age. Also increasing the estimate, it was assumed the "emission" was isotropic, meaning roughly the same in all directions. At least one peer reviewer said "firm conclusions may await an answer to the question of whether emission is beamed," presumably the way a pulsar is "beamed." [Pulsars are neutron stars, small but ungodly dense objects, the remnants of supernovas that are spinning many times per second, with fountains or jets of energetic particles being spewed out in two narrow beams along the magnetic poles.]
Even if estimates have to be revised, we know something big happened out there. The oldest model envisions GRBs result from the merger of two neutron stars. Another model has the core of a very massive star collapsing directly into a black hole, leaving a dense torus of material briefly orbiting. But it may not even take that much. It may just be the rapid gravitational collapse of about a solar mass of matter into a neutron star or black hole...
Nemesis: the search continues... Not only did the dinosaurs go extinct, but paleontologists have noticed in the oceanic fossil record that there were many mass extinctions throughout Earth's history, and quite a few of these extinctions occur in an eerily set pattern -- roughly every 25 million years or so, I believe it is. The Nemesis theory suggests that another star or a 'companion' star to the Sun periodically sweeps through its nearest orbit and perturbs our system's Oort cloud, resulting in more Earth-orbit-crossing comets and asteroids, which can have fairly significant effects on Earth ecosystems. As shown numerous times on the big screen recently, a properly placed cometary impact can definitely ruin someone's entire day.
At any rate, a couple of researchers at the University of Iowa recently measured with fair accuracy the velocity of Algol, a triple star system now 63 lightyears from our system. They calculated that Algol would have been within 13 lightyears a little over 4 million years ago, but their figures show that this isn't close enough to generate any increased cometary threat. Having six times the mass of the sun, if it was within 4 lightyears, Algol could trigger some of the Oort cloud comets to fall out of their distant orbits and essentially become solar slingshots, occasionally colliding with one of the inner planets. But luckily, they don't see Algol getting that close anytime soon.
Another star that was checked is "Gliese 710." With only half the mass of the sun, Gliese 710 would have to come within one lightyear to cause any gravitational anomalies. But a million years from now, Gliese 710 will only come within a comfortable 3 lightyears. No problem! Nemesis: the search goes on...
The expansion of the Universe is speeding up, not slowing down as was widely believed. This was reported in March 1998. I believe this finding is still rather tentative and has yet to be "duplicated" or otherwise supported independently. If true, though, this would necessitate a fairly major change in the prevailing cosmological model.
This would also imply that the vacuum itself must still contain a certain "expansion" energy that is counter to the "contraction" force of universal gravitation. Physics folks recognize this energy term as Einstein's cosmological constant. Yes, the same term Einstein later labeled as his "greatest blunder." Was he right in the first place? We'll see how well this finding holds up. Michael Turner of Fermilab says...
"With a slew of supernova observations awaiting analysis and several new... experiments set to measure the microwave background, the case for or against an anti-gravity force may be settled by 2000."
Early galaxies are already strongly clustered... In January 1998 Cal Tech's Charles Steidel and his colleagues announced that they had surveyed over 400 galaxies which are at least 12 billion lightyears distant. Such "old light" shows a time when the Universe was quite young. Surprisingly, the galaxies identified "are as strongly clustered in the early universe as they are today."
As I understand it, this would seem to support the "top-down" cosmological model, where initial structures are already large-scale. It hurts the "bottom-up" theory which starts in the small-scale and only later develops the larger-scale structures. This finding also lends support for the theory of cold dark matter, which has gravitational force but is not subject to the electromagnetic force, hence it is able to coalesce cosmologically sooner than ordinary matter, providing a kickstart to the overall structure that we observe.
Mexican ball court dated 3,400 years old. In Nature, April 30, 1998, Hill and Blake report on their unexpected discovery of a ball court in Pacific coastal Chiapas which is at least five centuries older than any previously excavated in Mesoamerica. This discovery demonstrates that formal ball courts "have been present from the very inception of settled village life."
By the time of the Spanish conquest, "ball courts were elaborate open-air masonry structures with two parallel platforms and a central alley where players competed to pass a rubber ball through a wall-mounted hoop. Ball games and their associated rituals were more than simple sporting events..."
The myth of glass as a liquid... Have you ever seen window panes in old houses (or stained glass windows in medieval cathedrals) which are thicker at the bottom? It was commonly thought the glass was slowly flowing downward like a viscous fluid. A new study calculated the time needed for viscous flow to noticeably change the thickness of glass. It was found that the required time is "well beyond the age of the universe." The difference in thickness in antique windows results from old manufacturing methods. Window glass was blown into a large globe, then flattened into a disk. Whirling the disk introduced ripples and thickened the edges. Structurally it makes sense to install the thick portions in the bottom of the pane. [Science News, May 30, 1998]
