Tenmon is a free and open source FITS XISF image viewer, converter, indexer application for Windows, Linux and MacOS. Using Tenmon you can view big astro photos and images easily. Currently it supports FITS, XISF, RAW CR2, DNG, NEF, JPEG, PNG, BMP, GIF, PBM, PGM, PPM and SVG image file types. It comes with WCS support, image statistics, OpenGL accelerated drawing and more.
Install Tenmon on Ubuntu Linux
Tenmon is available as a flatpak package from flathub. You need to install the flatpak and flathub on your system and restart it after the installation. Follow the below link for the flatpak and flathub installation instructions.
Now open the terminal software using ctrl+alt+t keys and run below Tenmon Image flatpak install command. It will install the latest version of Tenmon on your system.
flatpak install flathub space.nouspiro.tenmon
After that you can start the Tenmon app using this command.
flatpak run space.nouspiro.tenmon
And uninstall Tenmon using below command.
sudo flatpak uninstall space.nouspiro.tenmon