NGC 92 in H-alpha

The largest member of the galaxy group known as Robert''s Quartet is NGC 92, a spiral Sa galaxy with an unusual appearance. One of its arms, about 100,000 light-years long, has been distorted by interactions and contains a large quantity of dust. Using this H-alpha image obtained with FORS2 on the VLT, astronomers were able to study the properties of regions of active star formation ("HII regions"). They found more than 200 of such regions in NGC 92, with a size between 500 and 1,500 light-years.