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OK, we have a lot to get through this week. We have a new president coming along, and even though this charlatan may well usher in the end times, he is certainly known for grabbing ratings (among other things).  Also, last week, I promised to write about why I am having trouble with ‘Romance of three Kingdoms.”  It is a book about deceit, trickery, and cruelty as the tools of leadership. Perhaps now is a good time to talk about its dark lessons.  However before we get to any of that, today let’s take a quick trip off-world to our sister planet Venus (a planet which endlessly fascinates me) where some exceedingly strange developments have been in the works.

Venus is currently being monitored and observed by the Japanese Space Agency probe Akatsuki.  On December 7th, 2015, the probe spotted a huge crescent wave 6,000 miles long in the atmosphere of Venus. The probe lost sight of the massive bow shaped phenomena as it moved through its orbit, and, when it returned to position a few days later, the wave was gone.

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So what produces a 6,000 mile long super cloud on a planet already known for extreme fast moving clouds of sulfuric acid.  Scientists theorize that this was a gravity wave.  Gravity waves are not too be mistaken for the gravitational waves of deep space (which are caused by distortion of spacetime from supermassive objects).  Instead a gravity wave is a wave propagated within a fluid (like air or liquid) through the effects of gravity.  When water flows over a sandbar, gravity restores equilibrium on the other side–which causes a wave effect.  This is a familiar pattern in all sorts of fluid dynamics–including clouds passing over mountains.  It is believed that the giant crescent wave within the atmosphere of Venus originated from the atmosphere flowing over vast mountain ranges on the surface.

lenticular-cloud

Even if this is not as unfamiliar a phenomena as it might deem when first hearing the name and looking at the pictures, it is very beautiful and it is appearing on a scale hitherto unknown in terrestrial parts (although the supermassive planets have their own bizarre cloud structures which put it to shame.  for now lets just enjoy looking at the huge bow shaped cloud on the closest planet to Earth. Thanks JAXA for making this discovery! What will the strange hot caustic atmosphere of Venus do next?

 

 

Mind-blowing diagram comparing Vancouver to a Neutron Star (by Christian Joore)

Most items in the heavens are inconceivably large.  The sun, a fairly ordinary star has a diameter of 1,391,000 kilometers (864,327 miles).  Even a tiny planetoid like the moon has a diameter of 3,474 km (2,159 miles).  However a few noteworthy items in the heavens are so small that we can think of them in human terms—like neutron stars, which are the size of a town or small city with a diameter of only 20 or 30 kilometers (about ten to 15 miles  miles).   But even though they are the size of a small asteroid or Manhattan Island, neutron stars are hardly inconsequential.  These dinky stars can have more mass than the entire glorious sun (which itself is 332,946 times more massive than the Earth and everything on it).  A 1.27 cubic centimeter block of such material (approximately the size of a half an inch sugar cube) would weigh approximately the same as all of the human inhabitants of Earth (give or take).

Neutron stars are left-over fragments of supernovae explosions.  When a star 4 to 8 times more massive than our sun burns through all available fuel, its outer layers blow apart in a supernova which spreads glittering matter across great swaths of space.  The dense remaining portion of the stellar core undergoes a titanic battle between electron degeneracy pressure and gravity.  If the fragment has more than 1.44 stellar masses, gravity wins and the electrons and protons of its constituent matter are crushed into super dense neutrons.  Such explosions are tremendously dynamic and bright.  In 1054 AD, Sung dynasty astronomers recorded such an explosion which outshone the moon.  Contemporary astronomers have determined that the 1054 AD supernova created the Crab Nebula, an oval shaped mass of hydrogen, carbon, oxygen, nitrogen, neon, sulfur, and iron.

The Crab Nebula (which measures 11 light years across and lies 6,500 light-years from Earth) NASA/CXC/SAO/F. Seward

In the center of the Crab Nebula is a spinning neutron star which is emitting jets of particles at a tremendous velocity from its magnetic poles. These jets produce very powerful beams of electromagnetic radiation (which varies in intensity and wavelength according to elaborate nuclear & stellar physics, much of which is not yet understood).  The forces which create neutron stars often leave the stars spinning and pulsing with energy in such a way that they become pulsars.  These pulsars are useful for studying gravity, general relativity, and the behavior of matter at nuclear densities (albeit indirectly).  They also make accurate time measurement devices and useful beacons.  It is strange to think that stars so prominent for vast distances and so useful to astronomers actually have such minimal volume.

A Detailed x-ray image of the pulsar at the center of the Crab Nebula (Chandra)

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