Liquid oxygen sticks between the poles of a strong magnet until it
boils away into its gas state. This is because it has unpaired electrons, which make each oxygen molecule a tiny magnet
with a dipole. Normally, when oxygen is in a flask or in the air, these
microscopic magnets point in all directions, cancelling out and meaning that
there’s no net magnetic field. When it pours over the permanent magnet, the magnetic
molecules all slightly align, creating an induced
magnetic field, which reacts with the permanent magnet, making the oxygen stick
to the poles. This is called paramagnetism. Click here to watch the video.
The Craters of the Moon volcanic field in Idaho represents large outpourings of basaltic lava formed between 16000 and 2000 years ago. The full field covers an area the size of the state of Rhode Island; this is a tiny fragment of one of those lava flows, the Blue Dragon lava flow.
The texture you see is a signature of pahoehoe lava – once the lava is exposed at the surface its top layer cools and solidifies quickly while the center remains hot and continues flowing. Occasionally that lava breaks out at the edges of the flow, forming toe-shapes like these. However, it’s not the pahoehoe texture that is unique in this flow – it’s the color.
Scientists have discovered what are called “dead zones” in the
tropical North Atlantic, and they could potentially lead to mass fish
kills, according to new research.
Dead zones are areas of the ocean with extremely low levels of
oxygen. Most marine animals, like fish and crabs, cannot live within
these regions, where only certain microorganisms can survive. These
zones not impact the environment, but also are an economic concern for
commercial fishing. For example, very low oxygen concentrations having
been linked to reduced fish yields in the Baltic Sea and other parts of
And now, several hundred kilometers off the coast of West Africa,
a team of German and Canadian researchers have discovered the lowest
oxygen levels ever recorded in Atlantic open waters.
“Before our study, it was thought that the open waters of the North
Atlantic had minimum oxygen concentrations of about 40 micromole per
liter of seawater, or about one milliliter of dissolved oxygen per liter
of seawater,” lead author Johannes Karstensen, a researcher at GEOMAR,
the Helmholtz Centre for Ocean Research Kiel, in Kiel, Germany, said in a
Although this concentration of oxygen is low, most fish can still
survive in such waters. However, this latest study shows that the
minimum levels of oxygen are actually about 20 times lower than the
previous estimate, making the dead zones nearly void of all oxygen and
unsuitable for most marine animal