rhamphotheca:

End-Permian extinction happened in 60,000 years—much faster than earlier estimates, MIT study says

The largest mass extinction in the history of animal life occurred some 252 million years ago, wiping out more than 96 percent of marine species and 70 percent of life on land—including the largest insects known to have inhabited the Earth. Multiple theories have aimed to explain the cause of what’s now known as the end-Permian extinction, including an asteroid impact, massive volcanic eruptions, or a cataclysmic cascade of environmental events. But pinpointing the cause of the extinction requires better measurements of how long the extinction period lasted.

Now researchers at MIT have determined that the end-Permian extinction occurred over 60,000 years, give or take 48,000 years—practically instantaneous, from a geologic perspective. The new timescale is based on more precise dating techniques, and indicates that the most severe extinction in history may have happened more than 10 times faster than scientists had previously thought…

(read more: PhysOrg)

(Image: © John Sibbick / Natural History Museum)

spaceexp:

Successful full scale deployment and tensioning of the James Webb Space Telescope’s giant five layer sunshield system

  1. Camera: Nikon D4s
  2. Aperture: f/13
  3. Exposure: 1/40th
  4. Focal Length: 20mm
spaceexp:

SL9 Fragment Impacting Jupiter 20 Years Ago

spaceexp:

SL9 Fragment Impacting Jupiter 20 Years Ago

beatonna:

so confused 

todaysdocument:

Apollo 11 Astronauts Neil Armstrong and Buzz Aldrin make the first moonwalk, on July 20, 1969.

In these clips they can been seen planting the U.S. Flag on the lunar surface and experimenting with various types of movement in the Moon’s lower gravity, including loping strides and kangaroo hops.

Moonwalk One, ca. 1970

From the series: Headquarters’ Films Relating to Aeronautics, 1962 - 1981. Records of the National Aeronautics and Space Administration, 1903 - 2006

via Media Matters » Stepping Stones to the Moon

todaysdocument:

The Apollo 11 Moon Landing was televised worldwide and watched by 500-600 million, becoming a major cultural touchstone of the 1960s. Crowds from across the globe were mesmerized by the event, as shown in this clips from the film “Moonwalk One,” recently digitized by our colleagues in the National Archives’ Media Preservation Lab.

Moonwalk One, ca. 1970

From the series: Headquarters’ Films Relating to Aeronautics, 1962 - 1981. Records of the National Aeronautics and Space Administration, 1903 - 2006

via Media Matters » Stepping Stones to the Moon