The Milky Way in Unprecedented Clarity
This image was produced by combining infrared images taken during 144 orbits of the Hubble Space Telescope with images captured by the Spitzer Space Telescope.
The Hubble’s contribution to the panoramic image, which was released yesterday at a meeting of the American Astronomical Society, covers an area near the center of the Milky Way roughly 300 by 115 light years in size and is ten times sharper than the sections previously captured by the Spitzer Space Telescope. Astronomers use infrared light to capture images of this section of the galaxy as it is largely unaffected by dust in the region, whereas visible wavelengths are, for the most part, scattered and absorbed.
The sharper image reveals approximately 600,000 stars. The majority of the massive stars near the center of the Milky Way are found near its black hole or in either the Quintuplet or Arches star clusters, so it came as a surprise to find a new population of roughly 200 massive stars that appear to be in isolation.
The black hole, which appears in the image as a bright spiral within a torus of dust and gas, may be the reason for the rogue stars. Its approximate weight of 4 million Suns would produce such a massive gravitational force that it may have scattered the stars as it tore apart clusters that once occupied the surrounding region. Researchers are, however, unsure if the black hole is to blame or if the stars were simply born outside of the typical clusters.
Image credits: Hubble image: NASA/ESA/Q D Wang/UMass Amherst; Spitzer image: NASA/JPL/S Stolovy/Spitzer Science Center/Caltech
