• The Parker Solar Probe is set to uncover a mystery about the sun: Why is it's corona hotter than its surface?
  • NASA's ability to fly a probe so close to the sun is a marvel of engineering.
  • Michelle Thaller, an astronomer at NASA, explains why the Parker Solar Probe is so hot right now.
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This is not what an atom really looks like

Artistic depictions of the atom have deceived us all.

  • Though artistic renderings suggest otherwise, electrons do not, in fact, move around a nucleus the same way the planets move around a star — at all.
  • Electrons also are not tiny balls, they're more wavelike. Also, in regard to their location, a single electron can also be an entire sphere around the nucleus of an atom.
  • As for their movement, electrons do have a spin, but they're not actually spinning. They're not actually moving around. You can think of them as clouds that exist in different locations around the nucleus based on how much energy they have.
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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.
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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."
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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.
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