Vanessa Glau

Since falling in love with #sciencefiction, I have been curious about the #science behind it. This week was dedicated to reading and taking notes on The Future of Humanity in which futurist and physicist Michio Kaku discusses different ideas and possibilities for colonizing space and evolving into a multiplanetary species. Everything is explained in layman's terms so that even my non-physicist brain can understand and appreciate the wonders of the galaxy and human invention. Here's some intriguing slices of knowledge about our solar system.

Snowstorms

The huge, deadly layer of radiation surrounding the gas giant Jupiter is the source of much of the static we hear on radio and TV. Another small fraction of it comes from the Big Bang itself! This also means, however, that shielding from radiation will be a big priority for astronauts traveling near Jupiter in the future. All the interference would make communication difficult as well.

The goldilocks question

Planets or moons with liquid water are among the most interesting to scientists as they would be prime candidates for colonization. The range of distance from the sun or mother star with just the right temperatures for water to remain liquid is called the 'goldilocks zone' or habitable zone.

However, liquid water has been discovered outside of the goldilocks zone. Europa, one of Jupiter's moons, is covered with a thick smooth layer of ice. Underneath that ice there is a huge ocean of liquid water two to three times the size of all the Earth's oceans. This is because Europa's oceans make up most of its interior while Earth's oceans lie only on the surface.

Why does Europa have liquid water even though it is far outside the goldilocks zone? The answer is tidal forces. Jupiter's gravity is so great that it pulls and squeezes Europa at all times and the friction created by rocks being compressed inside the moon's core creates enough heat to melt the ice, at least on the inside of the moon.

Mercury's orbit

Mercury's orbit is weird and unique in the solar system. As explained in this article, the motion of planetary orbits rotating around the sun is called precession.

The orbits of the planets are slight ovals, with the sun located toward one end of the oval. The point at which the planet comes closest to the sun is the perihelion, and the farthest point of the oval is the aphelion. The oval orbits themselves move. As if the sun were a pin stuck into them, the orbits slowly rotate around it, in a motion called precession.

While this is accounted for by Newton's laws of motion, Mercury's orbit makes its round about 7% faster than predicted. At first, astronomers thought there was an undiscovered planet dubbed Vulcan tugging at it. That planet was never found though.

Eventually Albert Einstein showed that Mercury's orbit could be explained by the warping of space-time according to his general theory of relativity. It states that the more massive the star, the greater the warping of space-time around it. This warping does not affect planets far from the sun very much, but Mercury is so close to it that its strange precession is clearly noticeable. As a result, Mercury is tidally locked into a so-called 3:2 spin-orbit resonance.

UFO sightings

Have you ever wondered why the moon seems to be following you driving in your car? This is due to a phenomenon called parallax: We judge distances by moving our heads so that close objects like trees shift the most, while distant objects like mountains do not change position as much. Since objects immediately next to us like the car's steering wheel also do not seem to change position, we tend to confuse the moon with such an object and perceive it as if it was moving consistently alongside us.

Apparently many sightings of UFOs trailing after cars are actually sightings of the planet Venus that can be explained by parallax as well.

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Do you have similar science facts that might interest a curious fiction writer? Let me know on Twitter!