NASAさんのインスタグラム写真 - (NASAInstagram)「Galaxy NGC 6946 is nothing short of spectacular. In the last century alone, it has experienced 10 observed supernovae (the explosion of a star), earning its nickname as the Fireworks Galaxy. 🎆 In comparison, our Milky Way averages just one to two supernova events per century. This @NASAHubble image shows the stars, spiral arms, and various stellar environments of NGC 6946 in phenomenal detail. We are able to marvel at NGC 6946 as it is a face-on galaxy, which means that we see the galaxy “facing” us, rather than seeing it from the side (known as edge-on). The Fireworks Galaxy is further classified as an intermediate spiral galaxy and as a starburst galaxy. The former means the structure of NGC 6946 sits between a full spiral and a barred spiral galaxy, with only a slight bar in its center, and the latter means it has an exceptionally high rate of star formation. The galaxy resides 25.2 million light-years away, along the border of the northern constellations of Cepheus and Cygnus (The Swan). Image credit: ESA/Hubble & NASA, A. Leroy, K.S. Long #nasagoddard #Hubble #space #science #astronomy #spaceimage #spacepic #nasa」1月9日 4時55分