Most NASA engineers start at GS9 to 12 equivalent depending on education and prior experience. There is a COL allowance based on zip code. Overall they're making anywhere from 65-120k depending on where they live and what grade they come in. Government matches 5% via their 401k equivalent plan and you can get a pension after doing 20 to 30 yrs of service. Decent vacation and health care. Lots of jobs security.
Overall NASA is consistently ranked the best gov agency to work for. Some of their research and engineering is truly out of this world. Lots of cool stuff that industry would never fund. Some of their innovations are truly for the public good and increasing total human understanding of science, engineering, and space.