This spiral galaxy, NGC 2841, is helping NASA solve a huge mystery: why do galaxies look so smooth, with such an even distribution of stars?

According to NASA, studying NGC 2841 has helped an international team of astronomers discover that stars flow out of the "hot, dense nurseries" and then disperse to form the smooth distribution pattern that we usually see in similar spiral galaxies. This image is a composite of three different images from the Spitzer Space Telescope. The shorter wavelengths are represented in blue, and the show the oldest stars, plus foreground stars in our own galaxy. Green represents the medium wavelengths, and red is the longest wavelengths. [Spitzer Space Telescope]