astro-tasks software package provides Debian Astronomy Pure Blend (tasksel tasks), you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install astro-tasks
astro-tasks is installed in your system.
Make ensure the astro-tasks package were installed using the commands given below,
$ sudo dpkg-query -l | grep astro-tasks *
You will get with astro-tasks package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Science |
| Package | astro-tasks |
| Version | 0.5 |
| Description | Debian Astronomy Pure Blend (tasksel tasks) |
| Sub Section | Science |