What is called Boötes void?

Discovered by astronomer Robert Kirshner and his team in 1981, the Boötes void, sometimes called the Great Void, is a huge, spherical region of space that contains very few galaxies. It is approximately 700 million light years from Earth and located near the constellation Boötes, which is how it got its name.

The void measures 330 million light-years in diameter, representing approximately 0.27% of the diameter of the observable universe, which itself is estimated at 93 billion light-years across. It is the largest known void in the universe.

Astronomers were initially only able to find eight galaxies across the void expanse, but later observations have revealed a total of 60 galaxies. That might still seem like a lot, but the Milky Way has approximately two dozen galactic neighbours in a region of space 3 million light-years across. Using the average distance between galaxies elsewhere in the Universe as a few million light-years, and considering the volume of the Boötes void, then it should contain several thousands of galaxies.

Visitors to the area would surely feel isolation from the extreme distances between galaxies and the blacker-than-black view of distant space, with no starscape to gaze upon when looking into the night sky.