Hubble has snapped a spectacular view of the largest “player” in the Leo Triplet,
a galaxy with an unusual anatomy:
it displays asymmetric spiral arms and an apparently displaced core.
The peculiar anatomy is most likely caused by the gravitational pull
of the other two members of the trio.
This is the Hubblecast!
News and images from the NASA/ESA Hubble Space Telescope.
Hubblecast Episode 34: Hubble snaps heavyweight of the Leo Triplet
The unusual spiral galaxy, Messier 66, is located at a distance
of about 35 million light-years in the constellation of Leo.
Together with Messier 65 and NGC 3628, Messier 66 is one third of the Leo Triplet,
a trio of interacting spiral galaxies, part of the larger Messier 66 group.
Messier 66 wins out in size over its fellow triplets —
it is about 100 000 light-years across.
Messier 66 is the proud owner of exclusive asymmetric spiral arms
which seem to climb above the galaxy’s main disc
and an apparently displaced nucleus.
This asymmetry is unusual;
most often, dense waves of gas, dust and newly born stars
wind about the galaxy’s centre in a symmetric way.
Astronomers believe that Messier 66’s once orderly shape
has most likely been distorted by the gravitational pull of its two neighbours.
Hubble has imaged Messier 66’s striking dust lanes and bright star clusters
along the spiral arms in fine detail.
Star clusters — pictured in the blue and pinkish regions of the image —
are key tools for astronomers since they are used as indicators
of how the parent galaxies assembled over time.
Messier 66 boasts a remarkable record of supernovae explosions.
The spiral galaxy has hosted three supernovae since 1989,
the latest one occurring in 2009.
A supernova is a stellar explosion that may momentarily outshine its entire host galaxy.
It then fades away over a period lasting several weeks or months.
During its very short life the supernova radiates as much energy as
the Sun would radiate over a period of about 10 billion years.
Transcribed by ESA/Hubble