BANGKOK: The National Astronomical Research Institute of Thailand (Narit) is inviting the public to watch a lunar occultation of Venus on the evening of Monday (Sept 14, 2026), when the Moon will move in front of the planet in the western sky.
The phenomenon, which is rarely visible from Thailand, can be observed with the naked eye in many parts of the country, weather permitting. Narit will also hold free telescope-viewing events at four regional observatories.
For observers in Bangkok, the occultation will occur between approximately 7.28pm and 8.34pm.
The Moon and Venus will appear close together in the western sky after sunset. At around 7.28pm, the Moon will begin moving across Venus, gradually hiding the planet from view.
However, both objects will set at approximately 8.24pm, meaning observers in Bangkok will not be able to see Venus reappear when the occultation ends at around 8.34pm.
These times are calculated for Bangkok. The start and end times will vary for observers elsewhere in Thailand.
An occultation occurs when one celestial object moves across an observer’s line of sight, hiding another object behind it. Examples include the Moon passing in front of a planet or star, a planet obscuring a star, or one planet passing in front of another.
These events can support astronomical research, including calculations of the diameters of celestial objects and the distance between Earth and the Moon. They can also help scientists detect and study atmospheres and identify rings around the outer planets.
A lunar occultation of Venus is visible from only part of Earth, with the viewing area changing from one event to the next.
Because the Moon is relatively close to Earth, its apparent position in the sky varies according to the observer’s location. This limits how frequently people in any particular country, including Thailand, can witness the phenomenon.
Provided there are no clouds or rain obstructing the view, the event can be watched without special equipment.
Observers should choose somewhere with a clear western horizon, free from buildings, trees and other obstructions. Suitable locations include beaches, elevated viewpoints, open spaces and rice fields.
Through a telescope, viewers will be able to see Venus’s crescent shape as it gradually disappears behind the Moon.
Narit will hold free observation sessions from 6pm to 10pm on Sept 14, offering telescope views of the occultation and other celestial objects visible that evening.
The events will take place at its Regional Observatories for the Public in Nakhon Ratchasima, Khon Kaen, Chachoengsao and Songkhla. Admission is free at all four locations.
Throughout September, Venus will shine prominently in the western sky after sunset. In Thailand, it is commonly known in this evening appearance as “Dao Pracham Mueang”, or the evening star.
Venus will reach its brightest evening appearance of the year on Sept 22, 2026, and will remain visible until approximately 7.40pm. - The Nation/ANN
