Draco Dwarf Spheroidal

A team of astronomers analyzed observations by NASA's Hubble Space Telescope taken over a span of 18 years to measure the dynamic motions of stars within the Draco dwarf galaxy. The telescope's extensive baseline and data archive enabled the team to build the most accurate three-dimensional map of the stars' movements within the system. These improved measurements are helping to shed "light" on the mysterious qualities and behavior of dark matter, the universe's invisible "glue."

About the colours

These images are a composite of separate exposures acquired by the WFC3/UVIS and ACS instruments on the Hubble Space Telescope. Several filters were used to sample various wavelength ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors are: Cyan= F606W, Orange= F814W

About the data

The HST observations include those from program 12966 (R. van der Marel) and program 16737 (S.T. Sohn). Image Processing: Joseph DePasquale (STScI)