A new image captured by the Hubble Space Telescope shows the galaxy NGC 2217, a barred spiral galaxy that we see almost face-on from Earth, a situation that allows astronomers to study its structure with various instruments to try to understand its evolution. The bar passing through its center is quite faint in this galaxy, but astronomers think it’s important to funnel gas from the galactic disk to its center, where it could form new stars or be devoured by the central supermassive black hole.
About 65 million light-years from Earth, the galaxy NGC 2217, also known by other designations depending on the catalog, has a diameter of about 100,000 light-years, and this means that it’s similar in size to the Milky Way. It was discovered in 1835 by the English astronomer John Herschel and is the central galaxy of a group that, for this reason, is also known as NGC 2217.
Many stars of the galaxy NGC 2217 are concentrated around its nucleus while the rest of the disk is quite faint. For this reason, it’s sometimes classified as a lenticular galaxy, a class characterized by the scarcity of interstellar matter. A similar case can occur if gas was lost or was consumed by generations of stars. The consequence is that the most of the stars that compose it are old.
The bar that passes through the center of the galaxy NGC 2217 represents an interesting object of study within it for the role it has in its evolution. There are various discussions regarding the presence of a bar that passes through the center of the Milky Way: observations conducted with the Spitzer Space Telescope offered evidence of the existence of that type of formation, but the results led to the hypothesis that it’s temporary.
Seen from Earth, a bar of that type of galaxy looks like a continuous structure, but is actually made up of a group of stars just like the spiral arms, which are also faint in NGC 2217’s case. According to astronomers, the bar funnels gas towards the center of the galaxy, where it can form new stars or be devoured by the central supermassive black hole.
Seeing the galaxy NGC 2217 almost face-on is useful for observing it at its best. This image was captured by the Hubble Space Telescope’s Advanced Camera for Surveys (ACS) instrument using some optical frequency filters. Colors were also obtained using data from the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). Every detail can be useful to better understand the evolution of this galaxy and in general the processes that take place within a galaxy.