Magnitude +11.2 face-on spiral galaxy NGC 6814 lies in the constellation Aquila, 74.4 million light-years from Earth. Click the image for a full-size view. Image credit: ESA/Hubble & NASA. Acknowledgement: Judy Schmidt.Spiral galaxies together with irregular galaxies make up approximately 60 percent of the galaxies in the local Universe. However, despite their prevalence, each spiral galaxy is unique — like snowflakes, no two are alike. This is demonstrated by the striking face-on spiral galaxy NGC 6814, whose luminous nucleus and spectacular sweeping arms, rippled with an intricate pattern of dark dust, are captured in this NASA/ESA Hubble Space Telescope image.
NGC 6814 has an extremely bright nucleus, a telltale sign that the galaxy is a Seyfert galaxy. These galaxies have very active centres that can emit strong bursts of radiation. The luminous heart of NGC 6814 is a highly variable source of X-ray radiation, causing scientists to suspect that it hosts a supermassive black hole with a mass about 18 million times that of the Sun.
As NGC 6814 is a very active galaxy, many regions of ionised gas are studded along its spiral arms. In these large clouds of gas, a burst of star formation has recently taken place, forging the brilliant blue stars that are visible scattered throughout the galaxy.
Hubble Space Telescope observations have taken advantage of gravitational lensing to reveal the largest sample of the faintest and earliest known galaxies in the universe, formed just 600 million years after the Big Bang. Astronomers have determined, for the first time with some confidence, that these small galaxies were vital to creating the universe that we see today.
To understand the physics of the evolution and formation of galaxies it is crucial to know at what rate galaxies form stars, referred to as the star-formation rate. A group of researchers used Earth- and space-based telescopes to create a complete multi-wavelength picture of distant galaxies.
A supermassive black hole at the heart of galaxy NGC 1097 powers a brilliant nuclear ring of run-away star formation as imaged by the European Southern Observatory’s Very Large Telescope.
