StackImages · HR Diagram

HR Diagram of Your Own Image

Open an RGB FITS image of a star cluster, adjust the picture, and draw its Hertzsprung–Russell diagram the way the StackImages desktop app does.

1. Open an RGB fits file

Your image stays on this computer: it is read by Python running in this page. Up to 250 MB and 20 megapixels. A crop around the cluster works best and is faster.

Loading Python… The first visit downloads about 60 MB.

2. The picture

Your image appears here after you choose a file.

3. HR diagram

the magnitude given to the brightest star; empty means 10
fainter stars are left out; empty means 20