Astronomers create the most detailed portrait of the M106 galaxy.
The combined efforts of the NASA/ESA Hubble Space Telescope and two amateur astronomers has not only produced the best view of neighbouring spiral galaxy Messier 106 to date, but the exquisite detail of this 20 million light-year-distant star factory could have helped to explain why it appears to have four arms.
One of the brightest galaxies that we know of, M106 has an impressively active supermassive black hole at its centre which devours material that falls into it, and this heavyweight object’s insatiable appetite is thought to be responsible for the galaxy’s extra arms – which are not your standard spiral arms, but wisps of hot gas. “The two strange arms are either indications of an interaction of the jets with the galactic disc or indications of material from the jets falling back to the disc which then interact,” says Marita Krause from the Max-Planck Institute. “These ‘anomalous arms’ show no signs of star formation.”
Armed with Hubble images of the mysterious galaxy, amateur astronomer Robert Gendler added his own observations of M106 as well as those of fellow astrophotographer Jay GaBany to assemble a mosaic of this brilliant galaxy. “I realised this would be a massive project – the image would be a mosaic of more than 30 panels and would incorporate both wideband and narrowband data sets,” says Gendler, who was contacted by the Hubble Heritage Team for his assistance. “The anomalous arms emit light in the visual spectrum around 656nm (hydrogen-alpha) and I found a fair amount of hydrogen-alpha data for the arms in [this region].”