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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  • There is no way to shield astronauts on earth from the effects of gravity.
  • Astronauts train for space by going on an airplane that flies high at an arc so that the force lifts them in the air. However, we can only achieve about a minute's worth of weightlessness this way.
  • NASA researchers have nicknamed this plane the "Vomit Comet."

Is time real or is it an illusion?

Light exists outside of time.

  • Time can change depending on how fast you're moving through space. Also, time can "flow" at different rates for different observers.
  • Light doesn't experience time — it exists outside of time.
  • We perceive space and time differently, but they may be woven together. For instance, they both balance each other out: If you are still, time goes by at a natural rate. However, if you move through space very fast, time begins to slow down.