NGC 247 is a spiral galaxy in the Sculptor Group some 11 million light-years from Earth. This Hubble image shows a zoomed-in view of NGC 247’s central region. Click the picture for a larger-scale version that reveals more distant galaxies. Image credit: ESA/Hubble & NASA.This NASA/ESA Hubble Space Telescope image shows the central region of a spiral galaxy known as NGC 247. NGC 247 is a relatively small spiral galaxy in the southern constellation of Cetus (The Whale). Lying at a distance of around 11 million light-years from us, it forms part of the Sculptor Group, a loose collection of galaxies that also contains the more famous NGC 253 (otherwise known as the Sculptor Galaxy).
NGC 247’s nucleus is visible here as a bright, whitish patch, surrounded by a mixture of stars, gas and dust. The dust forms dark patches and filaments that are silhouetted against the background of stars, while the gas has formed into bright knots known as H II regions, mostly scattered throughout the galaxy’s arms and outer areas.
This galaxy displays one particularly unusual and mysterious feature — it is not visible in the image above, but can be seen clearly in wider views of the galaxy, such as the picture below from ESO’s MPG/ESO 2.2-metre telescope. The northern part of NGC 247’s disc (to the right in the following image) hosts an apparent void, a gap in the usual swarm of stars and H II regions that spans almost a third of the galaxy’s total length.This picture of the spiral galaxy NGC 247 was taken using the Wide Field Imager (WFI) on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile. Image credit: ESO.There are stars within this void, but they are quite different from those around it. They are significantly older, and as a result much fainter and redder. This indicates that the star formation taking place across most of the galaxy’s disc has somehow been arrested in the void region, and has not taken place for around one billion years. Although astronomers are still unsure how the void formed, recent studies suggest it might have been caused by gravitational interactions with part of another galaxy.
Twenty-five years ago this month, spacewalking astronauts installed corrective optics aboard the Hubble Space Telescope, correcting its famously blurred vision. Galaxy M100 was used to demonstrate the success of the repair, and the imagery has steadily improved since then.
Peering deep into the heart of our home galaxy, the Milky Way, the Hubble Space Telescope reveals a rich tapestry of more than half a million stars. Most of the stars pictured in the image are members of the Milky Way nuclear star cluster, the densest and most massive star cluster in the galaxy. Hidden in the centre is the Milky Way’s resident supermassive black hole.
A team of international scientists, led by astronomers from Cardiff University, has shown for the first time that galaxies can change their structure over the course of their lifetime. The researchers have shown that a large proportion of galaxies have undergone a major ‘metamorphosis’ since they were initially formed after the Big Bang.
