Abstract
By use of the values of the sky twilight brightness deduced at sea level at Abu Simbel in 1980 during the high solar activity period, the visibility of stars and planets of magnitudes less than 5.5 during twilight are obtained. The results are given in charts for each one degree of Sun's depression below the horizon. These charts can be applied for different altitudes above the horizon and different bearing angles from direction of sunset. Tables of corrections for different values of atmospheric attenuation and solar activity are given.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.