The NASA/ESA Hubble Space Telescope has provided astronomers a detailed new image of the barred spiral galaxy NGC 5668.
In this image of the barred spiral galaxy NGC 5668, Hubble was used to examine the surroundings of the Type II supernova event labeled SN 2004G, seeking to study the kinds of stars that end their lives as this kind of supernova. The color image is composed of near-infrared and optical observations from Hubble’s Advanced Camera for Surveys (ACS). Two filters were used to sample various wavelengths. The color results from assigning different hues to each monochromatic image associated with an individual filter. Image credit: NASA / ESA / Hubble / C. Kilpatrick.
NGC 5668 lies in the constellation of Virgo, approximately 90 million light-years away.
Otherwise known as IRAS 14309+0440, LEDA 52018 or UGC 9363, this galaxy was discovered on April 29, 1786 by the German-born British astronomer William Herschel.
NGC 5668 is a member of two groups of galaxies: the NGC 5638 group and NGC 5746 group.
“At first blush, NGC 5668 doesn’t seem like a remarkable galaxy,” the Hubble astronomers said.
“It is around 90,000 light-years across, similar in size and mass to our own Milky Way Galaxy, and its orientation nearly face-on to us shows open spiral arms made of cloudy, irregular patches.”
“One noticeable difference between the Milky Way and NGC 5668 is that this galaxy is forming new stars 60% more quickly.”
“This fact belies a galaxy with churning clouds and flows of gas, inclement weather that forms excellent conditions for the formation of new stars.”
The astronomers identified about two main drivers of star formation in NGC 5668.
“Firstly, this high-quality Hubble snapshot reveals a bar at the center,” they said.
“It might look more like a slight oval shape than a real bar, but it appears to have impacted the galaxy’s star formation rate, as central bars do in many spiral galaxies.”
“Secondly, high-velocity clouds of hydrogen gas have been tracked moving vertically between the disk of the galaxy and the spherical, faint halo which surrounds it.”
“These can be produced by the strong stellar winds of hot, massive stars, and they contribute gas to new star-forming regions.”
“The enhanced star formation rate in NGC 5668 comes with a corresponding abundance of supernova explosions,” they said.
“Three have been spotted in the galaxy, in 1952, 1954 and 2004.”
Source : Breaking Science News