Explore the Universe with Aperture Photometry Tool!

Aperture Photometry Tool (APT) is software for astronomical research, as well as for learning, visualizing and refining aperture-photometry analyses. Image overlays, graphical representations, statistics, models, options and controls for aperture-photometry calculations are brought together into a single package. Professional astronomers appreciate APT’s rich set of features and functions, and you will, too. APT is free of charge under a license that limits its use to astronomical research and education. It is perfect for the science center, observatory, and classroom. Also, it is quite simply the best FITS-image viewer you will find. Click here for a tutorial on Aperture Photometry Tool.