I believe it's this:

"SPOC, a navigation monitoring computer used by NASA in a 1983 mission, was a modification of a commercial computer called GRiD Compass, produced by GRiD Systems Corporation. ... SPOC automatically computes position, orbital paths, communication locations, etc. Some of the modifications were adapted for commercial applications."

http://spinoff.nasa.gov/spinoff/database/spinoffDetail.php?t...

Here's an Adafruit blog post with pictures of the hardware: https://blog.adafruit.com/2016/09/03/grids-compass-os-bootab...

This is the software that would've run on the Grid Compass [1] (coincidentally, one of the earliest laptop computers), which was flown on some early shuttle flights and was used to monitor and display ground position, orbital path, and some other stuff.

Basically, it was a UI to let astronauts monitor the shuttle's location in orbit. The shuttle's flight computers (especially at the time, prior to the glass cockpit upgrade) didn't really have a user interface to speak of; the SPOC gave them that.

[1] https://en.wikipedia.org/wiki/Grid_Compass

Here is what the Read me has to say:

"WORLD MAP"

The SPoC presently runs WORLD MAP as its primary program. A graphics display of a world map is overlaid by the Orbiter's current trajectory status. The following information/functions are available.

        Current MET
        Fixed coastline and Spaceflight Tracking and Data Network (STDN)/
        Tracking and Data Relay Satellite (TDRS) coverage graphics
        Day and night areas on the earth's surface
        AOS/LOS and identification of next/current ground communication site
        AOS/LOS and identification of next/current TDRS coverage
        Current and two predicted ground tracks
        Current position of the Orbiter on the world map
        AOS of the next earth observation site
        AOS of future earth observation sites
        Current F-stop
        F-stop for the selected earth observation site
        Predicted Site Acquisition Table (PSAT) Display
        Table of TDRSS AOS/LOS
        Communication/Earth Observation site reconfiguration
        Latitude and longitude of the Orbiter
        Time to Orbiter sunrise, noon, or sunset
        Sun glint position on the world map
        Sun glint look angles
        Longitude and MET of the next/previous ascending node
        Time until/from the next/previous ascending node

TL;DR: this is a map of the world. You put in the date and trajectory, and it charts where the shuttle is as it orbits the Earth, in real time. This map includes world-wide transmission stations, which basically follow the shuttle's orbit around the globe.

It was run on these laptops on the shuttle for years: https://en.wikipedia.org/wiki/Grid_Compass

It computes the position of the Shuttle orbiter in orbit at any point in time and displays a world map with the ground trace (the position on earth that the orbiter is over). It also has the coverage of the tracking network, so it can be used to predict when the shuttle is in contact with the ground.