Chandra Release - April 10, 2007

Visual Description: NGC 4258

  The image features a dramatic and colorful composite view of the spiral galaxy NGC 4258. The galaxy is predominantly colored in electric blue and purple, with bright red and gold. The galaxy takes the shape of a spiral, with a distinct bright center and unusual “extra” arms extending outwards. The arms appear to twist and curve around each other.  A combination of space and ground-based observations, including X-ray data from Chandra, helped reveal the nature of the unusual arms in NGC 4258. These arms have been known for decades, but their origin has remained mysterious to astronomers. In visible (shown in the gold) and infrared (red) light, two prominent arms emanate from the bright nucleus and spiral outward. These arms are dominated by young, bright stars, which light up the gas within the arms. But in radio (purple) and Chandra's X-ray (blue) images, two additional spiral arms are seen.