Tag Archives for art

The Nightmare

The Nightmare

Artist Johann Heinrich Füssli

Sleep paralysis is a phenomenon in which people, either when falling asleep or wakening, temporarily experience a sense of inability to move, similar to when an arm or leg goes to sleep, but not associated with numbness. More formally, it is a transition state between wakefulness and rest characterized by complete muscle atonia (muscle weakness). It can occur at sleep onset or when awakening. It is believed a result of disrupted REM sleep, which is normally characterized by complete muscle atonia that prevents individuals from acting out their dreams. Sleep paralysis has been linked to disorders such as narcolepsy, migraines, anxiety disorders, and obstructive sleep apnea; however, it can also occur in isolation. When linked to another disorder, sleep paralysis commonly occurs in association with the neuromuscular disorder narcolepsy.

Apollo 14 Moon Rock

Apollo 14 Moon Rock

Between 1969 and 1972 the National Aeronautics and Space Administration (NASA) successfully landed 12 astronauts on the lunar surface. The astronauts who visited the Moon carefully collected 2,196 documented samples of lunar soils and rocks weighing a total of 382 kilograms (843 pounds) during approximately 80 hours of exploration. It is important to note that these samples were gathered from a harsh lunar environment that included wildly fluctuating temperatures in an almost complete vacuum, dangerous solar radiation, and the uncertainty of return to Earth due to equipment failure.

Galaxy Evolution Discovery Surprises Scientists

Galaxy Evolution Discovery Surprises Scientists

Disk galaxies like our own Milky Way put the finishing touches on their stunning shapes relatively recently, a new study suggests.

Image: This spectacular image of the large spiral galaxy NGC 1232 was obtained on Sept. 21, 1998, during a period of good observing conditions. Credit: ESO

The find will likely surprise many scientists, who had thought such galaxies had been static for more than half of the universe’s 13.7-billion-year existence.

“Astronomers thought disk galaxies in the nearby universe had settled into their present form by about eight billion years ago, with little additional development since,” lead author Susan Kassin, of NASA’s Goddard Space Flight Center in Greenbelt, Md., said in a statement. “The trend we’ve observed instead shows the opposite — that galaxies were steadily changing over this time period.”

Kassin and her colleagues used NASA’s Hubble Space Telescope and the Keck Observatory in Hawaii to study 544 blue galaxies, whose color indicates that stars are forming within them.

They found that the most far-flung, ancient galaxies tend to be the most disordered, with organization steadily increasing as galaxies are observed closer and closer to the present day. Over time, the galaxies’ rotation speeds increase, and they settle into proper, well-behaved disks.

The trend holds for galaxies of all masses, but the biggest systems are always the most highly organized, researchers said.

“Previous studies removed galaxies that did not look like the well-ordered rotating disks now common in the universe today,” said co-author Benjamin Weiner of the University of Arizona. “By neglecting them, these studies examined only those rare galaxies in the distant universe that are well-behaved and concluded that galaxies didn’t change.”