Why are so many objects in space shaped like discs?

It's one of the most consistent patterns in the unviverse. What causes it?

  • Spinning discs are everywhere – just look at our solar system, the rings of Saturn, and all the spiral galaxies in the universe.
  • Spinning discs are the result of two things: The force of gravity and a phenomenon in physics called the conservation of angular momentum.
  • Gravity brings matter together; the closer the matter gets, the more it accelerates – much like an ice skater who spins faster and faster the closer their arms get to their body. Then, this spinning cloud collapses due to up and down and diagonal collisions that cancel each other out until the only motion they have in common is the spin – and voila: A flat disc.

China refutes U.S. claim that it's pushing space 'arms race'

"Here I want to remind all of you of a fact that the U.S. publicly defines outer space as a new battlefield," a Chinese foreign minister said.

U.S. Air Force
  • A Chinese foreign minister refuted U.S. claims that China and Russia are developing space weaponry.
  • China and Russia have recently ramped up cooperation on space programs.
  • Meanwhile, the U.S. has been skeptical of both nations, arguing that they're likely developing an array of space weapons.
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Spaceflight reactivates herpes virus in astronauts

A NASA-led study suggests the stress of spaceflight seems to trigger various types of herpes to reactivate in astronauts.

  • The study examined saliva, blood and urine obtained from astronauts who went on short- and long-term space missions.
  • The results showed that virus reactivation rates in these astronauts were much higher than controls.
  • Spaceflight seems to weaken the immune system, enabling these once-dormant viruses to reactivate and potentially cause serious health problems.
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Apparently even NASA is wrong about which planet is closest to Earth

Three scientists publish a paper proving that Mercury, not Venus, is the closest planet to Earth.

  • Earth is the third planet from the Sun, so our closest neighbor must be planet two or four, right?
  • Wrong! Neither Venus nor Mars is the right answer.
  • Three scientists ran the numbers. In this YouTube video, one of them explains why our nearest neighbor is... Mercury!
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Mining the Moon

How can we use the resources that are already on the Moon to make human exploration of the satellite as economical as possible?

The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE), a prototype heavy-lift utility vehicle to support future human exploration of extraterrestrial surfaces, at right, is parked beside the Habitat Demonstration Unit - Pressurized Excursion Module (HDU-PEM), at left, a concept off-Earth living and work quarters for astronauts stationed on asteroids, the moon or Mars, 15 September 2010. Photo by: ROBYN BECK/AFP/Getty Images

If you were transported to the Moon this very instant, you would surely and rapidly die. That's because there's no atmosphere, the surface temperature varies from a roasting 130 degrees Celsius (266 F) to a bone-chilling minus 170 C (minus 274 F). If the lack of air or horrific heat or cold don't kill you then micrometeorite bombardment or solar radiation will. By all accounts, the Moon is not a hospitable place to be.

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