As technology advances, so do plans for space exploration, as evidenced by the idea of a space elevator. Moreover, the Universe is immeasurable and replete with countless cosmic objects with amazing properties that deserve further scientific attention. In the meantime, here are 8 things that are (re)discovering about our Universe that might surprise you. 
1. Saturn can float on water
Known for its many rings, the planet Saturn is the 6th planet in the solar system, the most distant from our star, and the 2nd largest after Jupiter. Now imagine being able to sink this huge star into the heart of a giant ocean. Despite having a mass 95 times that of Earth, the planet will float. Why? Very simple, because the phenomenon of buoyancy is directly related to the density of the object, and not to its mass. Saturn's density (687 kg/m3) is lower than that of water (1000 kg/m3) because it is composed primarily of gas rather than solid matter like our blue planet.
2. The planets of the solar system do not revolve around the center of the Sun
Have you thought that the Earth revolves around the center of our star? Think again! The Sun itself revolves around a point - the barycenter of our Solar System. All bodies influence each other under the influence of gravity, and the more massive the object, the greater the force of its attraction. Only the Sun has the greatest mass in its immediate vicinity (99.854% of all bodies in the system). Thus, this central point is located approximately 750,000 kilometers from the center of the Sun, slightly above its outer layer.
3. A quarter of a billion years later, the Earth returns to its starting point
Everything in the Universe rotates. Without this rotational motion there would be no accumulations of gas and dust, no stars. Besides, life could not exist.
The Earth rotates around itself at a speed of 1,600 km/h at the equator and moves around the Sun at a speed of 107,000 km/h. The solar system orbits the Milky Way's central supermassive black hole, Sagittarius A*, at more than 850,000 km/h. One complete revolution of 165,000 light years, which corresponds to one galactic year, takes 230 million years. This means that the last time our planet was in the same position as it is today in relation to Sagittarius A*, dinosaurs walked the soil of our good old Earth.
4. Supermassive black holes will be less dangerous for astronauts than stellar black holes
It would be very interesting for the world of astrophysics to be able to get inside black holes if humanity ever gets there. However, this journey will be one way for everyone who decides to go there.
However, supermassive black holes (on the order of several million to several billion solar masses) will be much "softer" than stellar ones (on the order of several solar masses) because their tidal forces are weaker and their singularity is much further from the horizon than their smaller cousins. When approaching a black hole of just a few solar masses, these forces would instantly kill the daring astronaut before he or she even crossed the event horizon. This is a spaghetting phenomenon that is caused by differential gravitational force and tends to stretch any object.
5. Uranus “rolls” in its orbit, and Venus’s rotation is retrograde
Our blue planet has an axis of rotation tilted 23° to the perpendicular of its orbit around the Sun. All neighboring planets have an axis tilt ranging from 0° to 30°. The only exceptions are two planets. Uranus' axis is tilted at 98°, causing the effect of rolling along its stellar trajectory, like a billiard ball thrown at high speed. Venus, on the other hand, has an axis closer to 177°. Therefore, it rotates in the opposite direction compared to its counterparts. This is called retrograde rotation.
6. Mastodon stars
To get up to speed, let's start by assessing the characteristics of the Sun. Its diameter is about 1,400,000 kilometers, and its mass is about 2 × 10^30 kg (2 and 30 zeros). This sounds phenomenal to us, but our star looks like a baby compared to some giants.
R136a1, the most massive star known, is located 170,000 light-years from Earth. Located at the heart of the Tarantula Nebula in the Large Magellanic Cloud galaxy, it is 265 times heavier than the Sun and 10 million times brighter. According to scientists, the maximum mass of a star should not exceed 150 solar masses. So this is a strange case that astronomers are trying to explain.
The largest star that can be observed is in the constellation Scutum, at a distance of 5,000 light years. Its name is UY Shield. At 1,700 times the size of our star (more than two billion kilometers in diameter), this red supergiant may contain, brace yourself, more than 3.6 billion Suns.
7. Jupiter, the failed star
We are used to waking up with only one sun. However, binary and multiple systems are commonplace in space. According to astrophysicists, the Sun may have had a satellite during its long life of ten billion years.
Jupiter, the largest planet in our vicinity, has a diameter of 143,000 km at the equator. Moreover, 1300 Earths could easily be squeezed into it. The gas giant might have started nuclear reactions like the Sun if the protoplanet 4.3 billion years ago had collected much more space debris during the formation of the solar system. Because its mass was too small for nuclear fusion to occur, the body never ignited and remained forever part of the family of planets orbiting the Sun.
8. Jupiter's Great Red Spot
This large reddish eye is a storm of enormous power. Slightly larger than Earth, it has wind speeds of over 700 km/h. It was first observed in 1665, and since then this high-pressure system has continued to sweep through Jupiter's atmosphere. Moreover, it is so large that a small telescope with a diameter of 15 cm is sufficient to observe it.
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