The NASA/ESA Hubble Space Telescope has captured a stunning new image of a flocculent spiral galaxy called NGC 3521.
This Hubble image shows the spiral galaxy NGC 3521. The image was taken by the Wide Field and Planetary Camera 2 (WFPC2) on board Hubble. Image credit: NASA/ ESA / Hubble / S. Smartt, Queen’s University Belfast / Robert Gendler.
NGC 3521, also known as the Bubble Galaxy, is a mere 46 million light-years away, toward the constellation Leo.
It was discovered by the British astronomer William Herschel in 1784.
Through his larger, 47-cm aperture, telescope, Herschel saw a ‘bright center surrounded by nebulosity,’ according to his observation notes.
The object is easily visible in small telescopes but often overlooked by amateur imagers in favor of other Leo spiral galaxies.
Spanning about 50,000 light-years, NGC 3521 has a bright and compact nucleus.
Like other flocculent galaxies, this spectacular galaxy lacks the clearly defined, arcing structure to its spiral arms that shows up in galaxies such as Messier 101, which are called grand design spirals.
In flocculent spirals, fluffy patches of stars and dust show up here and there throughout their discs.
Sometimes the tufts of stars are arranged in a generally spiraling form, as with this galaxy, but illuminated star-filled regions can also appear as short or discontinuous spiral arms.
About 30% of galaxies share NGC 3521’s patchiness, while 10% have their star-forming regions wound into grand design spirals.
