[Previous] | [Session 87] | [Next]
A.A. Maciolek (Grosse Pointe North High School), R.J. Maddalena (NRAO)
High frequency observations with the NRAO Green Bank Telescope are affected by atmospheric conditions. Water vapor and the atmospheric stability influence radio waves by increasing the opacity of the atmosphere and degrading the quality of the "seeing." Although Green Bank is located in a temperate climate, preliminary studies using data from an 86 GHz tipping radiometer and a 12 GHz phase monitoring interferometer suggest that about 30% of the time (~100 days/year) conditions will be excellent for observations at 100 GHz.
This project attempts to determine in detail what atmospheric conditions produce simultaneously optimal seeing and opacity. We examined fifty-one periods of good observing that occurred over a period of 100 days. The analysis looks for patterns between twenty-five different weather parameters, drawn from a combination of surface, satellite, and vertical atmospheric measurements. Our preliminary results indicate that conditions of good opacity and good seeing do occur simultaneously and we can frequently predict good observing conditions from a combination of temperature, wind direction, pressure, and water vapor.
>From this research, two high school projects were developed for students taking an introductory one semester astronomy course. In the first, students use data from the Observatory and four surrounding weather stations, as well as geographical and climatic information of the area, to create and test an interpolated vertical profile of the atmosphere over Green Bank. In the second, students analyze weather parameters on a set of poor observing days and compare their results with those of the good-weather study described above.