Moon night sky brightness simulation for Xinglong station

TL;DR

This study measures and models the moon night sky brightness at Xinglong station, using observational data to improve telescope survey planning and understanding of sky brightness variations.

Contribution

It introduces a modified moon night sky brightness model and applies it to simulate sky conditions for telescope survey optimization at Xinglong station.

Findings

Sky brightness correlates with human activity during dark nights.

Derived typical parameters for moon night brightness model.

Simulated sky brightness for telescope survey planning.

Abstract

With a sky brightness monitor in Xinglong station of National Astronomical Observatories of China (NAOC), we collected data from 22 dark clear nights and 90 lunar nights. We first measured the sky brightness variation with time in dark nights, found a clear correlation between the sky brightness and human activity. Then with a modified sky brightness model of moon night and data from moon night, we derived the typical value for several important parameters in the model. With these results, we calculated the sky brightness distribution under a given moon condition for Xinglong station. Furthermore, we simulated the moon night sky brightness distribution in a 5 degree field of view telescope (such as LAMOST). These simulations will be helpful to determine the magnitude limit, exposure time as well as the survey design for LAMOST at lunar night.