MI weekly selection #196
Faraway galaxy made mostly of dark matter
A Milky Way-sized galaxy made up almost entirely of dark matter has been spotted 300 million light years away, and now researchers are looking for one similar to Dragonfly 44 that’s closer to the Milky Way so they might be able to finally detect the mysterious matter. “We think that this galaxy is representative of an entirely new class of object,” said Pieter van Dokkum, lead author of a study published in Astrophysical Journal Letters.
Tiny amounts of water may be present in seasonal Mars’ streaks
A tiny amount of water may be present in dark streaks, called recurring slope lineae, or RSL, on Mars that appear on the planet’s surface during its spring and summer seasons. Researchers studied years of surface-temperature measurements taken by instruments aboard the Mars Odyssey to assess the soil’s water content.
Bacteria spread Lyme disease throughout body via blood vessels
Researchers have discovered how the bacteria that causes Lyme disease uses blood vessels to spread the illness throughout the body. Borrelia burgdorferi form and then break bonds with the vessel walls, in effect swinging from vessel to vessel with the help of the bacterial protein BBK32, and treatments targeting that protein may limit the disease’s spread.
Researchers identify cooling nerve cells in feverish mice
Nerve cells that cool the body have been found in the hypothalamus of mouse brains, according to a study published in Science. The cells contain the protein TRPM2, which reacted to cool off the body when the mice experienced fevers.
Rats remember in reverse to recall where to find tasty treats
Rats replay memories in reverse in order to recall where they found the tastiest food, a new study in Neuron suggests. Researchers charted the brain activity of rats with electrodes implanted in their hippocampi as they retraced their steps to a reward of liquid chocolate.