Short answers, pulled from the story.
The Indian mathematician and astronomer Brahmagupta proposed that gravity is an attractive force drawing objects to Earth in 628 CE. He used the term gurutvākarshana to describe this pull.
Isaac Newton published his groundbreaking book Philosophiæ Naturalis Principia Mathematica in 1687. It unified terrestrial acceleration with celestial mechanics under one universal law.
Albert Einstein developed general relativity in 1915 to explain Mercury's orbital eccentricity. Astronomers noticed the planet's perihelion increased by about 42.98 arcseconds per century before his theory accurately modeled the orbit.
The LIGO observatory detected faint gravitational waves on the 14th of September 2015. Waves originated from a black hole merger occurring 1.3 billion light-years away.
About five-sixths of total universal mass consists of dark matter interacting only through gravity without electromagnetic interactions. Dark matter halos attract hydrogen leading to star and galaxy formation.