A study on the visibility limit of stellar occultations with the Moon at sunset and sunrise

JOURNAL OF OCCULTATION AND ECLIPSE (JOE); ISSN 2522-7955; No. 1, 2014

H. Hekmat'zade^1,2, N. Taebjoula^1,2, A. Poro¹, M. Zakerin^1,3

¹International Occultation Timing Association-Middle East Section (IOTA-ME), Iran; info@iota-me.com

²Dez Sky scholars Institute, Iran

³Jahrom University, Physics department, Jahrom, Fars, Iran

Abstract

In this paper, we try to find new criteria for both the degree of visibility and timing of the occultation of stars by the Moon at sunset and sunrise in the presence of the sky backlight. To do so, distinct Moon phases were observed in different weather conditions and locations, always taking into account the important parameters such as apparent magnitude of the star, the altitude of the sun below the horizon, as well as the angular separation between the sun and the Moon. Our designed observations proved that the previous criteria defined by Mr. Dave Gault can be improved. Following, additional observations were performing to determine the new visibility limit of the stellar occultation by the Moon at a specific time.

Keywords: Occultation, Moon, visibility