Galactic Center

The Galactic Center (or Galactic Centre) is the rotational center of the Milky Way galaxy.

Baade's Window on the Milky Way

The Galactic Centre, as seen by one of the 2MASS infrared telescopes, is in the bright upper left portion of the image

The crowded centre of the Milky Way

It is a supermassive black hole of 4,100 ± 0.034 million solar masses. It powers the compact radio source Sagittarius A*.^[1][2][3][4]

It is 8 ± 0.4 kiloparsecs (26,100 ± 1,300 ly) away from Earth^[5] in the direction of the constellations Sagittarius, Ophiuchus, and Scorpius where the Milky Way appears brightest.

Baade's window

Walter Baade searched for the centre of the Milky Way galaxy in the mid-1940s. He used the 100-inch (2.5 m) Hooker telescope at Mount Wilson Observatory in California.

Up until then the structure and position of the galactic center was not known for sure.^[6]

In 2006, the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS) conducted a survey of 180,000 stars for seven days. The objective was to detect extrasolar planets by the transit method.^[7]

OGLE and other observation programs have successfully detected extrasolar planets orbiting around central bulge stars in this area by the gravitational microlensing method.