Hubble Space Telescope Zooms in on Markarian 178
Astronomers using the NASA/ESA Hubble Space Telescope have captured a stunning 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 about 13 million light years away in the constellation 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,” Hubble astronomers said in a statement.
“These galaxies take their name from Armenian astrophysicist Benjamin Markarian, who compiled a list of galaxies that are surprisingly bright in ultraviolet light.”
“While most of the galaxy is blue due to the abundance of young, hot stars surrounded by little dust, Mrk 178 takes on a red hue from a collection of massive stars, particularly concentrated in the brightest reddish region near the edge of the galaxy.”
“This azure cloud is home to a large number of rare objects called Wolf-Rayet stars.”
“Wolf-Rayet stars are massive stars that shed their atmosphere thanks to powerful winds,” the astronomers explained.
“Because Mrk 178 contains many Wolf-Rayet stars, the bright emission lines from the hot stellar winds of these stars are etched into the galaxy’s spectrum.”
“Highly ionized hydrogen and oxygen appear red on Mrk 178 in this photo, observed using some specialized Hubble light filters.”
“Massive stars enter the Wolf-Rayet phase just before collapsing into black holes or neutron stars.”
“Since Wolf-Rayet stars only last a few million years, we know that something must have triggered a recent burst of star formation in Mrk 178.”
“At first glance, the cause is unclear: Mrk 178 does not appear 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 that its gas may have been disrupted as the galaxy swims through the intergalactic medium, lighting this small galaxy with a ripple of bright new stars.”
