The existence of dark matter is inferred from various astronomical observations, such as the gravitational effects on galaxies and the large-scale structure of the universe. Dark matter is believed to be a form of matter that does not interact with light or other electromagnetic radiation, hence its name. It does not emit, absorb, or reflect light, making it difficult to directly detect or observe.
While we have not yet directly detected dark matter particles, its presence is strongly supported by its gravitational effects on visible matter. It is estimated that dark matter makes up about 85% of the total matter in the universe, while ordinary matter, which includes the Earth and everything we can see, accounts for only about 15%.
Regarding the presence of a large amount of dark matter around the Earth, the prevailing scientific understanding is that dark matter is distributed throughout the universe, including our galaxy, the Milky Way, and its immediate vicinity. This includes the region around the Earth. The current models suggest that there should be a significant amount of dark matter passing through our planet at any given time.
However, detecting dark matter on a smaller scale, such as around the Earth, is challenging because it interacts so weakly with ordinary matter. Scientists have been conducting various experiments in underground laboratories and using sensitive detectors to try to directly detect dark matter particles. So far, no conclusive direct detection has been made.
While it is possible that our current technology and knowledge are not yet sufficient to detect or observe dark matter directly, ongoing research and future advancements in experimental techniques may provide further insights into this mysterious component of the universe.