Image Credit: Credit: NASA/NOAA/GSFC/Suomi NPP/VIIRS/Norman Kuring
This image of the Earth from space makes an excellent wallpaper for your computer.
Via Flickr
Here’s another excellent photo via APOD, and it looks great as computer wallpaper!
More on this image via APOD:
Explanation: Fix your digital camera to a tripod, start a long series of exposures, and you too can record star trails. The concentric arcs traced by the stars as planet Earth rotates on its axis often produce dreamlike scenes in otherwise familiar situations. Fall asleep, though, and the results might surprise you. Setting up on a summer night, photographer Mike Rosinski began his exposures, initially planning to capture about 45-55 minutes worth of star trails from his yard in Hartland, Michigan, USA. But he dozed, only to awaken some 3 hours later to find his camera had continued to run until the battery died. Composing the resulting images, the graceful concentric star trails were expected, along with light from a late rising Moon glinting on windows. Still, as he slept on the warm night a blizzard of yellow streaks flooded the scene, not left by fairies but fireflies.
This image, via APOD, was constructed by sandwiching two night skies, showing the Milky Way, from two different locations — one from each hemisphere.
More via APOD:
Explanation: A quest to find planet Earth’s darkest night skies led to this intriguing panorama. In projection, the mosaic view sandwiches the horizons visible in all-sky images taken from the northern hemisphere’s Canary Island of La Palma (top) and the south’s high Atacama Desert between the two hemispheres of the Milky Way Galaxy. The photographers’ choice of locations offered locally dark skies enjoyed by La Palma’s Roque de los Muchachos Observatory and Paranal Observatory in Chile. But it also allowed the directions to the Milky Way’s north and south galactic poles to be placed near the local zenith. That constrained the faint, diffuse glow of the plane of the Milky Way to the mountainous horizons. As a result, an even fainter S-shaped band of light, sunlight scattered by dust along the solar system’s ecliptic plane, can be completely traced through both northern and southern hemisphere night skies.
Voyager 1 and Voyager 2 are about to pierce the heleosphere, which protects our solar system from cosmic radiation, and enter interstellar space. The probes have already collected a wealth of data about our solar system, and they’re now collecting data about the edge of our solar system and soon, they’ll collect data about what lies beyond our solar system.
In addition to collecting information about our solar system and what lies beyond, each probe also contains a special record that contains information about our planet and humanity. Via NASA:
Each probe is famously equipped with a Golden Record, literally, a gold-coated copper phonograph record. It contains 118 photographs of Earth; 90 minutes of the world’s greatest music; an audio essay entitled Sounds of Earth (featuring everything from burbling mud pots to barking dogs to a roaring Saturn 5 liftoff); greetings in 55 human languages and one whale language; the brain waves of a young woman in love; and salutations from the Secretary General of the United Nations. A team led by Carl Sagan assembled the record as a message to possible extraterrestrial civilizations that might encounter the spacecraft.
“A billion years from now, when everything on Earth we’ve ever made has crumbled into dust, when the continents have changed beyond recognition and our species is unimaginably altered or extinct, the Voyager record will speak for us,” wrote Carl Sagan and Ann Druyan in an introduction to a CD version of the record.
Image via la picarita on Flickr
Anthropogenic activities are resulting in rapid habitat degradation, loss, and fragmentation, which fuel more extinctions of species that can’t adapt to human-dominated environments. This period of Earth’s history, which is dominated by human activities, is often referred to as the anthropocene. According to recent research, mass extinction, which is currently fueled by an increase of human populations and activities, may forever change the outcome of evolution. More via Wired.com:
Rates of species diversification — the speed at which groups adapt and fill open ecological niches — seemed to predict what’s flourished in the aftermath of past planetary cataclysms. But according to the calculations of Macquarie University paleobiologist John Alroy, that’s just not the case.
“Mass extinction fundamentally changes the dynamics. It changes the composition of the biosphere forever. You can’t simply predict the winners and losers from what groups have done before,” he said.
. . .
In the past, many evolutionary biologists thought life would eventually recover its present composition, said Alroy. In 100 million years or so, the same general creatures would again roam the Earth. “But that isn’t in the data,” he said.
Instead Alroy’s analysis suggests that the future is inherently unpredictable, that what comes next can’t be extrapolated from what is measured now, no more than a mid-Cretaceous observer could have guessed that a few tiny rodents would someday occupy every ecological niche then ruled by reptiles.
“The current mass extinction is not going to simply put things out of whack for a while, and then things will go back to where we started, or would have gone anyway,” said Alroy. Mass extinction “changes the rules of evolution.”
The author or licensor of this image does not endorse my work or me and their image is protected under an attribution license.
