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.
This NASA/ESA Hubble Space Telescope image captures the glow of distant stars within NGC 5264, a dwarf galaxy located just over 15 million light-years away in the constellation of Hydra (The Sea Serpent). NGC 5264 clearly possesses an irregular shape — unlike the more common spiral or elliptical galaxies — with knots of blue star formation.
While truly massive stars go out in a blaze of glory, intermediate-mass stars — those between roughly one and eight times the mass of the Sun — are somewhat quieter. Such stars eventually form cosmic objects known as planetary nebulae, so named because of their vague resemblance to planets when seen through early, low-resolution telescopes.
Some of the Milky Way’s “celebrity stars” — opulent, attention-getting, and short-lived — can be found in this Hubble Space Telescope image of the glittering star cluster called Trumpler 14. It is only 500,000 years old, has one of the highest concentrations of massive, luminous stars in the entire Galaxy and is located 8,000 light-years away in the Carina Nebula.