This image shows LEDA 42160, a galaxy
about 52 million light-years from Earth in the constellation Virgo. The
dwarf galaxy is one of many forcing its way through the comparatively
dense gas in the Virgo cluster, a massive cluster of galaxies. The
pressure exerted by this intergalactic gas, known as ram pressure, has dramatic effects on star formation in LEDA 42160, which are presently being studied using the Hubble Space Telescope.
LEDA 42160 falls into the category of ‘Magellanic spiral galaxy’, or type Sm for short, under the de Vaucouleurs galaxy classification system. Magellanic spiral galaxies can be further sub-categorised as barred (SBm), unbarred (SAm) and weakly barred (SABm), where a ‘bar’ is an elongated bar-shape at a galaxy’s core. Generally speaking, Magellanic spiral galaxies are dwarf galaxies with only one single spiral arm. They are named after their prototype, the Large Magellanic Cloud, which is an SBm galaxy. Magellanic spiral galaxies are an interesting example of how galaxy categorisation is actually more nuanced than simply ‘spiral’, ‘elliptical’ or ‘irregular’.