The effect of gravity continues to shape celestial entities like our very own galaxy. This shifting of gravity can also have smaller effects. Mineralogy of meteorites from Earth gives us 250 different minerals in a variety of meteorites, because we know what materials were present in the local stars, we can tell that these minerals likely came about from the forming and fracturing of planetesimals. Clays, Mica, and Zircon all become the building blocks of Earth and other rocky planets. At the very least in our section of the milky way, the Orion Arm, our very own spiralised arm address.

This may have happened because of the galactic coalition between The Milky Way and Gaia Enceladus, the resulting turmoil of gravity and introduction of more gasses and dust lead to there being an increase in stars, estimated to be about 10 times higher than it is today. Because the stars within our galaxy are that much closer we are able to determine their age a lot better, and because we know about the various interactions our galaxy has with other celestial objects it helps us determine what caused these fluctuations in star formation.

The amount of gas available in the disk has been depleted and the disk stops actively creating new stars.

We know a little more about this collision than the first. We also know that Sagittarius Dwarf and the resulting fragments collided with the Milky Way multiple times. Parts of it can still be seen in the far reaches of the galaxy, and will likely collide again. There are so many types of celestial bodies within the Milky Way, planets come in many varieties. Tidally locked planets; where one side is always in starlight, the other in darkness. Occurring when the rotation of a planet matches its orbit around its star. Hot Jupiters; Gas giants that orbit close and fast to their suns, usually completed within five days. As a result they are extremely hot, forming cloud droplets made from molten glass and high wind speeds. There are moons with cryovolcanism such as Miranda, Titan, and Ganymede. All of which are found in our solar system. Enceladus is a planet with sub-oceans under a 60-kilometre ice sheet. Our astronomical ecosystem is varied and wondrous, these collisions were probably the cause of an explosion of star formations, which included our own yellow giant, the Sun.

Some solar systems have multiple stars, the most common in our galaxy are double star systems, but there are triple systems as well, and in just one of these solar systems we have our home. The rocky inner planets Mercury, Venus, Earth and Mars formed when intense pulses of solar winds separated hydrogen and helium from the heavier elements, carbon, nitrogen, oxygen phosphorus and sulphur, sweeping the lighter gaseous elements outwards to the domain of the giant planets, Jupiter, Saturn, Uranus and Neptune. The same separation effect can be seen in the structure of Earth, heavier molecules collect and settle at the centre, forming the metal-rich core. There are of course more details that brought the Earth’s structure as we know it into being.