18-Months Operation of Lunar-based Ultraviolet Telescope: A Highly Stable Photometric Performance

TL;DR

The Lunar-based Ultraviolet Telescope (LUT) demonstrated highly stable photometric performance over 18 months on the Moon, with consistent zero points and no performance degradation, supporting its use for future lunar astronomy.

Contribution

This study provides the first long-term stability assessment of a lunar-based telescope's photometric performance over 18 months.

Findings

Photometric stability maintained over 18 months

Zero point consistency across spectral types

No performance evolution observed

Abstract

We here report the photometric performance of Lunar-based Ultraviolet telescope (LUT), the first robotic telescope working on the Moon, for its 18-months operation. In total, 17 IUE standards have been observed in 51 runs until June 2015, which returns a highly stable photometric performance during the past 18 months (i.e., no evolution of photometric performance with time). The magnitude zero point is determined to be $17.53\pm0.05$ mag, which is not only highly consistent with the results based on its first 6-months operation, but also independent on the spectral type of the standard from which the magnitude zero point is determined. The implications of this stable performance is discussed, and is useful for next generation lunar-based astronomical observations.