Science Sunday 07-01-17

Colony Collapse Disorder

The ongoing concern about declines in honey bee populations worldwide recently made the news again, with a report that neonicotinoid insecticides may play a significant role in colony collapse disorder, a process wherein a healthy bee colony simply disappears (dies off) within a very short time.

Using 33 test sites in Germany, Hungary and England, the researchers determined that neonicotinoids can have a devastating effect on a honey bee colony, depending on how exclusively the bees fed on crops sprayed with these chemicals.

The above Kurzgesagt video well summarizes all the causes of colony collapse disorder, and why the disappearance of bees is such an alarming development.

Better Than Flight Simulator?

Apparently, 360 degree videos are all the rage now, and I am just catching up.  Here we see a 360 video of a complete Airbus 320 flight, from taxi through takeoff, to approach and landing.  You can swivel your view to see what is going on in the entire cockpit, and you can decide what portion of the flight you want to watch or rewatch.

Water Water Everywhere

The nature of dihydrogen oxide, commonly known as water in its liquid state, has been a subject of fascination for me for some time, so I was surprised to find out that physicists now seem firmly convinced that water has two liquid states, one below 40 degrees Celsius and one above 60 degrees Celsius.  The “interphase” range between 40 to 60 Celsius degrees is viewed as a transition range within which various properties of water change abruptly at different temperatures.

You can read about this new development here.

A Possible New Planet in Our Solar System

We all know that Pluto, which we just visited, in no longer considered a solar system planet, but has instead been demoted to the status of dwarf planet, one of five so far recognized by the International Astronomical Union.  Dwarf planets are Trans-Neptunian Objects (TNOs), as they reside farther out than Neptune in our solar system.  They are also called Kuiper Belt Objects (KBOs), as they reside at least part of the time in the Kuiper Belt, which is region in the solar system that is between 30 and 50 astronomical units (AUs) from the Sun.  An astronomical unit is roughly the average distance from the Earth to the Sun, about 93 million miles).

Now comes a new report by researchers from the University of Arizona that a distinct group of KBOs exhibit a common behavior different from most other solar system objects.  The common plane of these KBOs’ orbits are nearly 8 degrees off from the “invariable plane” of most all other solar system objects.  The researchers reason that this is due to a “Mars sized planet” heretofore undetected and residing in the outer regions of the Kuiper Belt.  The researchers are careful to point out that their hypothesized planet (and it would be a real planet if it were the size of Mars) should not be confused with another hypothesized planet, called Planet Nine, that is thought to be 10 times the size of  Earth and be much father out in the solar system (about 700 AU).

Newton’s Third Law

Veritasium has posted a video about a new “water toy” that stably suspends most any lightweight ball at the top of a vertically ascending water jet.  Apparently the jet causes the ball to spin away from it.  The ball carries the water around it in such a way that the water pushes the ball back towards the water jet, producing a hydrodynamic equilibrium state..

To quote our fearless leader, Enjoy!

 

 

Advertisements

Science Sunday 06-18-17

How We All Got Here

In roughly the time it takes for light to get from the Sun to the Earth, astrophysicist Neil de Grasse Tyson explains how the Universe evolved from the Big Bang to us safely ensconced here on Earth.  Courtesy of Minute Physics.

Chocolate and A Fib

Chocolate not only tastes good, but you may need to indulge in its pleasures to avoid or reduce the effects of atrial fibrillation.

Tis The Season

The Summer Solstice moment, the beginning of Summer, is nearly upon us, coming early in the morning of June 21st in sunny old England and late in the previous day in toddling Chicago, where I live.

The Summer Solstice is marked by being the day with the most sunshine for us northern hemispherians.  In Chicago, at roughly 42 degrees north latitude, we will enjoy 15 hrs and 14 minutes of Mr. Sunshine.

Londoners by contrast will enjoy 1 hr and 23 minutes more of direct sunshine, because London is nearly 10 latitude degrees farther north than Chicago.

Chicagoans get a “free” additional 68 minutes of indirect lighting (civil twilight) every day of the year, with half of that time in the morning (dawn) and half of it in the evening (dusk).  Londoners receive an astounding additional 95 minutes of indirect lighting, again because they are 10 latitude degrees farther north than Chicago.

It is fun to observe the shadows cast by street sign poles on the “longest day”.  Here is Chicago, the shadow will be a little more than 35 degrees south of east at sunset.

V Sauce Michael above talks at length at issues regarding time and our planet’s motion relative to the Sun in the video above.

To play with your location’s sunrise, sunset, and civil twilight times, visit this delightful site.

The Bigger They Are

The deeper they live.  I speak of deep sea gigantism, aka abyssal gigantism, the tendency of sea dwelling invertebrates to grow larger the deeper in the oceans they live.  Examples abound: the giant isopod, the giant amphipod, the Japanese spider crab, the giant oarfish, the deepwater stingray, the seven-arm octopus, and a number of squid species including the colossal squid (up to 14 m in length) and the giant squid (up to 13 m).

No one knows for sure why there is this tendency, but one speculation is that the larger the body, the lower the skin surface to body mass ratio, an important characteristic for creatures living in very cold water and high hydrostatic pressure, where conversation of body heat is a matter of life and death.

A related rule called Bergmann’s rule states that crustaceans tend to be larger the higher in latitude they are observed.  A similar rule applying to humans called Allen’s rule is supported by observation that indigenous people living at higher latitudes have shorter limbs.

For a more general review of the mysteries of the barely explored deep ocean, check out this fascinating video:

Schlieren Imaging

There’s an old type of dimly lit photography (and videography) called shlieren imaging that reveals the subtle differences in densities (and refractive indices) of moving fluids, like hot air ascending from a burning match, or the ejecta from your mouth and nose when you sneeze.  Veritasium’s video above is a great take on this cool optical phenomenon.

Science Sunday 06-03-17

Popular Science Cassini Retrospective

CassiniEarth

Popular Science has put together an amazing retrospective collection of images from NASA’s Cassini spacecraft.  It’s just one web page, so it will probably blow out your browser’s temporary memory, but check it out anyway.  There are quite a few worthy wallpaper images you can use.  Click on the link above to see this collection.

The white dot next to the arrow is Earth.

Icarus Redux

NASA just announced that it will be sending a probe to the Sun to study the Sun’s corona and its solar wind, among other things.

The probe is named after University of Chicago professor Eugene Parker, who first hypothesized the existence of a supersonic solar wind emanating from our star.

The probe will launch in July of 2018 and will fly to within 6.2 million kilometers of the Sun.  That’s about 96% of the way from the Earth to the Sun, so the probe will have to withstand very high temperatures and immense solar radiation.

Minority Report

The BBC reports that Dr. Doris Tsao has shown that a mere 200 neurons in a monkey’s brain completely specify the image seen and remembered by the monkey.

Dr. Tsao was able to take the excitation pattern of the 200 neurons and recreate with remarkable accuracy the image that the monkey actually saw.

In principle, this means that at least for visual memories, it might soon be possible to “read” a person’s mind and accurately recreate the visual image the person is seeing in her mind.  Police could use this technique to produce significantly more faithful “sketches” of an eyewitness’ visual account of a reported criminal.

A New Ripple From Outer Space

Scientists at Caltech have just announced that a third gravitational wave (or space-time ripple) has been detected.  The wave detected is due to two black holes merging after circling each other.  The combined mass of the two black holes was estimated to be 49 solar masses (49 times the current mass of the Sun).

The two LIGO observatories have localized this latest collision to a spot 3 billion light years away, meaning the event detected in January, 2017, actually occurred 3 billion years ago.  Talk about ancient history!

The previous two instances of gravitational wave detection were also black hole mergers, the first having a combined mass of 62 solar masses, and the second having a combined mass of 21 solar masses.

For a primer on gravitational waves and why they are so important, check out this video:

Godel’s Incompleteness Theorems

As is often the case, I stumbled upon a series of Numberphile2 videos about a fellow named Godel who basically showed that there are some truths (statements known incontrovertibly to be true) that cannot be proven within the axiomatic boundaries of mathematics.

The above video (which is the third of three videos) deals with the suggestion that maybe theology can invoke Godel’s theorems to “save itself” from the ongoing assault of science on various religious assertions.