Skychart is astronomical observatory software that is written using Lazarus, a pascal IDE, which in turn is written using free pascal, http://www.ap-i.net/skychart/index.php . Skychart has more functionality than Night Vision which is available for OS/2 in that it can drive a motorized mount and camera and allows additional star catalogues to be added as well as mapping the local horizon to the display.
There is already a free pascal available for OS/2 at http://www.freepascal.org/
Lazarus is at http://www.lazarus.freepascal.org/ but doesn't currently compile under the OS/2 version of fpc. Lazarus uses gtk1/2 or Qt for it's graphics rendering and there is a port of Qt at netlabs. How up to date that is I don't know.
Both fpc and Lazarus are attempting to achieve write anywhere/ run anywhere so in itself would likely open up what software was available. It is aimed to be Delphi compatible. Currently the fileutils for Lazarus only have Windows and Unix calls available and I don't know how to add the OS/2 ones but I presume the units must exist within the OS/2 version of fpc for it to be available. I'm sure there will be other problems as well and I don't know how to tell Lazarus to use qt either. The fileutils uses IFDEFS to decide on which units to use and if I knew what IFDEF to use for OS/2 I might be able alter the fileutils and find the next problem.