Astronomers using the NASA/ESA Hubble Space Telescope have captured a striking photo of the ultra-diffuse galaxy GAMA 526784.
This Hubble image shows GAMA 526784, an ultra-diffuse galaxy some 4 billion light-years away in the constellation of Hydra. Image credit: NASA / ESA / Hubble / R. van der Burg / L. Shatz.
Ultra-diffuse galaxies are objects as large as our Milky Way Galaxy but with 100-1,000 times fewer stars.
First discovered in 2015, they are extremely faint and lack star-forming gas, which makes them appear almost like a fluffy cosmic cloud.
Their origins remain uncertain, but astronomers speculate that they could be ‘failed’ galaxies that lost their gas supply early in their lifetimes.
“Ultra-diffuse galaxies such as GAMA 526784 have a number of peculiarities,” Hubble astronomers said.
“For example, their dark matter content can be either extremely low or extremely high — ultra-diffuse galaxies have been observed with an almost complete lack of dark matter, whereas others consist of almost nothing but dark matter.”
“Another oddity of this class of galaxies is their anomalous abundance of bright globular clusters, something not observed in other types of galaxies.”
The ultra-diffuse galaxy GAMA 526784 is located approximately 4 billion light-years away in the constellation of Hydra.
It was discovered in 2015 by astronomers using the Anglo-Australian Telescope as part of the Galaxy And Mass Assembly (GAMA) survey.
The new image of GAMA 526784 comes from a set of Hubble observations designed to shed light on the properties of ultra-diffuse galaxies.
Hubble’s keen vision allowed astronomers to study this galaxy in high resolution at ultraviolet wavelengths, helping to gauge the sizes and ages of the compact star-forming regions studding the galaxy.
The color image was made from separate exposures taken in the visible and near-infrared regions of the spectrum with Hubble’s Advanced Camera for Surveys (ACS).
Two filters were used to sample various wavelengths. The color results from assigning different hues to each monochromatic image associated with an individual filter.
“The ACS instrument was installed in 2002 by astronauts during Hubble Servicing Mission 3B,” the researchers said.
“Since then, the instrument has played a pivotal role in some of Hubble’s most impressive scientific results, including capturing the Hubble Ultra Deep Field.”
“The ACS has also photographed Pluto in advance of NASA’s New Horizon mission, observed gargantuan gravitational lenses and found fully formed galaxies in the early Universe.”
Source link: https://www.sci.news/astronomy/hubble-ultra-diffuse-galaxy-10739.html
