Demystifying galaxy tides

  What is a galaxy tidal
  tides in coastal areas is a common natural phenomenon, referring to the sea in the celestial (mainly the moon and the sun) periodic motion under gravity produced.
  This kind of phenomenon also exists between galaxies in the universe, which is called galaxy tide. When two galaxies are close together, it will cause strong tidal forces. This strong tidal force will cause different forces on various parts of the two galaxies and cause changes in their shapes. The front part of the two galaxies attracts each other due to tidal force, while the tail part due to the small tidal force, the stars and gas in these areas will lag behind, forming a tidal tail. For example, the Twin Mouse Galaxy and the Tentacle Galaxy are two prominent examples of tidal tails caused by collisions (see picture).
  Galactic tides brought to Earth
  comet showers
  edge of the solar system is the Oort cloud, here is the headquarters of the comet. The comet orbits the sun in an orbit that is 100,000 times greater than the distance between the earth and the sun. However, scientists have discovered that every 30 million years the earth will usher in a shower of comets. Why would comets come to visit the earth? What mysterious force “regularly” disrupts their orbits, causing comets to enter the inner solar system and fall into the earth? This confuses scientists.
  Recent studies have shown that the tidal motion of galaxies in the Milky Way may be the reason why comets hit the earth on a regular basis.
  Scientists analyzed the material left by the comet in the crater on the earth and found that the meteorites are about 30 million years apart. Another more convincing point is: the orbit of the solar system itself, it fluctuates up and down the plane of the Milky Way every 30 million years, which causes other galaxies in the Milky Way to produce changes in the tidal force of the solar system. This change changed the orbit of the comet and brought the “regular” shower of the comet to the earth.
  Galaxy tides may affect the evolution of life on Earth
  The galaxy tides in the Milky Way are strong enough to affect comets in the Oort Cloud, which means that it may also affect life on Earth. The tides of the moon have always been a force that has always existed in the history of the earth, helping the earth to shape all kinds of life landscapes. It is now also believed that the galaxy tides of the Milky Way may have also played an important role in the evolution of the Earth.
  We already know that the tides of the moon are crucial to the evolution of life on earth. The constant ebb and flow of the ocean brings life at sea to land, forcing these creatures to adapt to the living conditions on land. Astrobiologists also believe that comet showers brought by tides have also played an important role in the evolution of life on Earth. According to photos taken by the polar satellites launched by NASA, there is continuous space precipitation on the periphery of the Earth’s atmosphere. This unknown “comet rain” not only brings abundant water resources to the earth, but also contains primitive chemical substances such as hydrogen, oxygen, nitrogen and carbon. These substances may even be related to the origin of life on the earth.
  Recently, Japanese scientists claimed that they proved through experiments that the early comet impact on the earth might convert amino acids into peptides, which became the earliest building blocks of life on earth. This discovery can not only explain the origin of life on Earth, but may also have an impact on the existence of extraterrestrial life.
  What key role did galaxy tides play in the origin and evolution of life on Earth? Scientists still have a lot of work to do in the future.