Asked by Megan Davies
Spiral galaxies usually rotate in such a way that the arms trail, with the tips of the spiral arms winding away from the centre of the galaxy in the same direction as the galaxy’s disc. However, NGC 4622, also referred to as the backward galaxy, leads with the tips of its arms.
Some experts suggest that this may be the result of a gravitational interaction between itself and another galaxy, while others have put forward an idea that the backwards galaxy may be the result of a merger between itself and a smaller object.
The idea of a galaxy that leads with its spiral arms was originally met with scepticism because it contradicted conventional thought. However, further observations of the galaxy have confirmed its motion.
Image Credit: NASA