Characterizing Atmospheric Seeing Over the ITB Campus Using DIMM
Naufal Muhammad Dzaky Widodo, Syauqi Nawawi, Eugene Timothy Clay, Fahmi Aziz Firmansyah, Luthfiana Sutarjo, Muhammad Zaki Gumilang, Cut Vanya Putri Azaria

Astronomy Department / Faculty of Mathematics and Natural Science, Institut Teknologi Bandung

Abstract

Atmospheric seeing is a critical parameter in ground-based astronomy: it quantifies atmospheric quality, limits angular resolution, and factors into signal-to-noise calculations for optimal exposure times. At the Astronomy Department of Institut Teknologi Bandung (ITB), our small observatory is regularly used for student projects, yet no comprehensive study of local seeing conditions exists. Here, we report on an ongoing Differential Image Motion Monitor (DIMM) campaign to characterize seeing around the ITB campus from June to October 2025. Our preliminary analysis reveals a mean seeing value of 1.115 \pm 0.316 arcseconds, with ongoing investigations into (1) temporal variability, (2) its dependence on target altitude recognizing that airmass increases at low elevations, and (3) comparisons to the theoretical airmass power-law model S(X) = S_{0}X^{3/5} (where S_{0} is the zenith seeing and X is the airmass). These initial findings suggest strategies for optimizing observational practices at ITB and contribute to understanding urban seeing conditions in the tropics.

Keywords: seeing, Differential Image Motion Monitor, time-series seeing, airmass, atmosphere

Topic: Instrumentation in Astronomy