AstroStack is an easy-to-use astronomical imaging and processing tool geared towards the use of inexpensive webcam CCDs. It provides a very tunable environment to produce the best quality images. It supports the following features: tunable webcam sampling; image stacking (averaging, additive etc.); pre and post-capture gamma (brightness) and contrast correction; dark-shot CCD calibration (subtractive); and an internal 16-bit grey-scale format for optimal resolution.
WCSLIB is a C library, supplied with a full set of Fortran wrappers, which implements the "World Coordinate System" (WCS) standard in FITS (Flexible Image Transport System). It also includes a PGPLOT-based routine, PGSBOX, for drawing general curvilinear coordinate graticules, and a number of utility programs. The FITS "World Coordinate System" (WCS) convention defines keywords and usage which provide descriptions of astronomical coordinate systems in a FITS image header.
GRALE is a set of tools - a library and a number of accompanying applications - to study gravitational lenses. Gravitational lenses are astronomical objects so massive that their gravitational pull even deflects light rays. This can cause multiple copies of the same background object to be visible, like a cosmic mirage. The locations and shapes of these copies can provide information about the mass distribution of the gravitational lens, which GRALE can help recover using a genetic algorithm-based method. Apart from these so-called lens inversions, it's also possible to simulate gravitational lenses.
The satpass script provides satellite visibility predictions, given the position of the observer and the NORAD element sets for the desired satellites. It can acquire the NORAD element sets directly from any site supported by Astro::SpaceTrack. It can acquire the observer's latitude and longitude from http://geocoder.us/, look up star positions in the SIMBAD catalog, and more.
ChiantiPy is a Python interface to the CHIANTI atomic database for astrophysical spectroscopy. The CHIANTI atomic database for astrophysical spectroscopy provides the information necessary to calculate the emission spectrum from hot plasmas. ChiantiPy provides several top-level classes to access the database and calculate continuum and emission line intensities.
AstroAviBrowser is a small tool for astronomy imaging capture/processing. It allows you to open a video file, select the good frames, and save the new sequence in a new avi file using raw or lossless codecs. You may also de-bayer your frames and separate RGB plans. It's a kind of "AviRaw" for Linux.
Qastrocam-g2 is a fork of the Qastrocam project, Webcam capture software for astronomy. This fork adds support for RGB24 (luminance only) and YUYV. It has better generic V4L support (lx mode and resizing). Settings backup has been added. There is better parallel and serial lx mode support. There are a number of other changes and additions.
Sunrise Sunset is a Python package that can determine the sunrise and sunset based on a given altitude zenith. It has two public methods. The first returns the sunrise and sunset in a tuple. The second returns True or False depending on whether the supplied date/time is during the night or day. The constructor takes three arguments, a date, latitude, and longitude. There is one keyword argument for changing the default zenith, which is set to "official". The zeniths are "official", "civil", "nautical", "amateur" (astronomical), and "astronomical". It does not rely on third party packages, but you may need something like pytz to create dates with timezone info.