Astronomers using the NASA/ESA Hubble Space Telescope have captured an amazing new photo of the blue compact dwarf galaxy Markarian 178.
This Hubble image shows the blue compact dwarf galaxy Markarian 178. Image credit: NASA / ESA / Hubble / F. Annibali / S. Hong.
Markarian 178 is located approximately 13 million light-years away in the constellation of Ursa Major.
Also known as Mrk 178, LEDA 35684 or UGC 6541, the galaxy has a diameter of 5,700 light-years.
“Mrk 178 is one of more than 1,500 Markarian galaxies,” the Hubble astronomers said in a statement.
“These galaxies get their name from the Armenian astrophysicist Benjamin Markarian, who compiled a list of galaxies that were surprisingly bright in ultraviolet light.”
“While the bulk of the galaxy is blue owing to an abundance of young, hot stars with little dust shrouding them, Mrk 178 gets a red hue from a collection of massive stars, which are especially concentrated in the brightest, reddish region near the galaxy’s edge.”
“This azure cloud is home to a large number of rare objects called Wolf-Rayet stars.”
“Wolf-Rayet stars are massive stars that are casting off their atmospheres through powerful winds,” the astronomers explained.
“Because Mrk 178 contains so many Wolf-Rayet stars, the bright emission lines from these stars’ hot stellar winds are etched upon the galaxy’s spectrum.”
“Particularly ionized hydrogen and oxygen appear as a red color to Mrk 178 in this photo, observed using some of Hubble’s specialized light filters.”
“Massive stars enter the Wolf-Rayet phase just before they collapse into black holes or neutron stars.”
“Because Wolf-Rayet stars last for only a few million years, we know that something must have triggered a recent burst of star formation in Mrk 178.”
“At first glance, it’s not clear what could be the cause — Mrk 178 doesn’t seem to have any close galactic neighbors that could have stirred up its gas to form new stars.”
“Instead, we suspect that a gas cloud crashed into Mrk 178, or its gas may have been disturbed as the galaxy swims through the intergalactic medium, lighting up this tiny galaxy with a ripple of bright new stars.”
