NGC 685 is rich in star-forming nebulae, seen as glowing pink clouds in the new image from the NASA/ESA Hubble Space Telescope.
This Hubble image shows the barred spiral galaxy NGC 685. The color image was made from separate exposures taken in the ultraviolet, visible and near-infrared regions of the spectrum with Hubble’s Wide Field Camera 3 (WFC3). It is based on data obtained through six filters. The color results from assigning different hues to each monochromatic image associated with an individual filter. Image credit: NASA / ESA / Hubble / J. Lee / F. Belfiore.
NGC 685 is located approximately 64 million light-years away in the southern constellation of Eridanus.
Otherwise known as ESO 152-24, IRAS 01458-5300 or LEDA 6581, the galaxy was discovered by the British astronomer John Herschel on October 3, 1834.
It is about 74,000 light-years across, and has a bright center bar and patchy, curving arms.
“NGC 685 is classified as a barred spiral galaxy because its feathery spiral arms sprout from the ends of a bar of stars at the galaxy’s center,” the Hubble astronomers said in a statement.
“The Milky Way is also a barred spiral, but our Galaxy is a little less than twice the size of NGC 685.”
The astronomers used Hubble to study NGC 685 for two observing programs, both of which focus on star formation.
“It’s no surprise that NGC 685 was chosen for these programs: numerous patches of young blue stars highlight the galaxy’s spiral arms,” they said.
“Many of these star clusters are cocooned in pink gas clouds, which are called H II regions.”
“An H II region is a gas cloud that glows for a short time when particularly hot and massive stars are born.”
“An especially eye-catching H II region peeks out at the bottom edge of the image.”
“Despite the dozens of star-forming regions evident in this image, NGC 685 converts an amount of gas equivalent to less than half the mass of the Sun into stars each year.”
“The Hubble data collected for the two observing programs will allow us to catalogue 50,000 H II regions and 100,000 star clusters in nearby galaxies.”
“By combining Hubble’s sensitive visible and ultraviolet observations with infrared data from the NASA/ESA/CSA James Webb Space Telescope and radio data from the Atacama Large Millimeter/submillimeter Array, we will peer into the depths of dusty stellar nurseries and illuminate the stars forming there.”
