Context: Recently, the Hubble Space Telescope is tracking down a suspected black hole that shredded a wayward star that came too close for comfort.
Background

• The famed space observatory made the find while hunting down the source of a powerful burst of X-rays caught in 2006 by two other cosmic telescopes: NASA's Chandra X-ray Observatory and the European Space Agency's X-ray Multi-Mirror Mission (XMM-Newton).

Key Findings

• Astronomers have long studied supermassive black holes and smaller black holes that form when massive stars implode, but they have searched for intermediate-mass black holes for years.

• Now, thanks to observations by the Hubble Space Telescope, astronomers have found their "missing link" to understand how black holes evolve. They were able to confirm the observation of an intermediate-mass black hole, known as an IMBH, inside a dense cluster of stars.

• At the time, astronomers weren't sure if the X-rays had come from inside or outside of the Milky Way galaxy, but new high-resolution photography by Hubble shows that the X-ray source (known as 3XMM J215022.4−055108) is located in a star cluster at the edge of another galaxy.  
• The team's work further suggests the star cluster may have been the core of a small dwarf galaxy disrupted long ago, when the dwarf galaxy strayed too close to the larger galaxy that currently hosts the star cluster. 
• Gravitational interactions with the larger galaxy may have ripped the dwarf galaxy apart, leaving only a small cluster of stars in its wake. In much the same way, astronomers believe that the gravitational pull of the black hole inside this cluster shredded a star that got too close, thereby producing the X-ray flare detected in 2006. 
• IMBHs(intermediate-mass black hole) have been particularly difficult to find because they are smaller and less active than supermassive black holes; they do not have readily available sources of fuel, nor as strong a gravitational pull to draw stars and other cosmic material which would produce telltale X-ray glows. 
• IMBHs are believed to be a "missing link" in our understanding of how black holes evolve. Astronomers have seen many examples of small black holes that are similar in size to a star, and other examples of much larger black holes that typically reside in the centers of galaxies. But IMBHs remain difficult to confirm as astronomers struggle to understand how supermassive black holes got so big, compared to stellar-sized black holes. 
• Hubble also helped track down another possible IMBH in 2009. The object, called HLX-1, was spotted on the edge of a galaxy known as ESO 243-49, and also resides in a star cluster that could have been a dwarf galaxy in the ancient past.
• Studying the origin and evolution of the intermediate mass black holes will finally give an answer as to how the supermassive black holes that we find in the centers of massive galaxies came to exist.