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The galaxy UGC 8201,
captured here by the NASA/ESA Hubble Space Telescope, is a dwarf irregular
galaxy, so called because of its small size and chaotic structure. (NASA.gov
image)
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NASA.gov – The galaxy UGC 8201
is a dwarf irregular galaxy, so called because of its small size and chaotic
structure.
It lies just under 15 million light-years away from us in the constellation
of Draco (The Dragon)
As with most dwarf galaxies it is a member of a larger group of
galaxies
In this case UGC 8201 is part of the M81 galaxy group; this group
is one of the closest neighbors to the local group of galaxies, which contain
our galaxy, The Milky Way.
UGC 8201 is at an important phase in its evolution.
It has recently finished a long period of star
formation, which had significant impact on the whole galaxy.
These stars can be seen in this image as the dominating
light source within the galaxy. This process also changed the distribution and
amount of dust and gas in between the stars in the galaxy.This episode lasted
for several hundred million years and produced a high number of newborn bright
stars.
Such large star
formation events need extensive sources of energy to trigger them.
This raises an important
unanswered question in galaxy evolution: How do relatively isolated, low-mass
systems such as dwarf galaxies sustain star formation for extended periods of
time? However, compared to larger galaxies, dwarf galaxies lack such sources
and they do not appear to have enough gas to produce as many new stars as they
do.
Due to its relative
proximity to Earth UGC 8201 is an excellent object for research and provides an
opportunity to improve our understanding of how dwarf galaxies evolve and grow.
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