Sky Survey -SDSS-III map

* 이 사진의 점 하나는 60억년전의 은하의 위치를 가리킨다. 우리 은하도 저런 점 하나밖에 안된다.

Image credit: Daniel Eisenstein and the SDSS-III collaboration
A slice through a map of our Universe

This is one slice through the map of the large-scale structure of the Universe from the Sloan Digital Sky Survey and its Baryon Oscillation Spectroscopic Survey. Each dot in this picture indicates the position of a galaxy 6 billion years into the past.

The image covers about 1/20th of the sky, a slice of the Universe 6 billion light-years wide, 4.5 billion light-years high, and 500 million light-years thick.  위 사진의 범위는 (넓이 60억 광년 x 높이 45억 광년 x 두께(깊이?) 5억 광년 의 범위) - sky (천구?)의 1/20 

Color indicates distance from Earth, ranging from yellow on the near side of the slice to purple on the far side.

Galaxies are highly clustered, revealing superclusters and voids whose presence is seeded in the first fraction of a second after the Big Bang. This image contains 48,741 galaxies, about 3% of the full survey dataset. Grey patches are small regions without survey data.

Image credit: Jeremy Tinker and the SDSS-III collaboration

A section of the three-dimensional map constructed by BOSS

The rectangle on the far left shows a cutout of 1000 sq. degrees in the sky containing nearly 120,000 galaxies, or roughly 10% of the total survey. The spectroscopic measurements of each galaxy — every dot in that cutout — transform the two-dimensional picture into a three-dimensional map, extending our view out to 7 billion years in the past. The brighter regions in this map correspond to the regions of the Universe with more galaxies and therefore more dark matter. The extra matter in those regions creates an excess gravitational pull, which makes the map a test of Einstein’s theory of gravity.  - SDSS July 14, 2016