Astronomers said the Sun and the Moon cannot appear brightly side by side on the horizon, contrary to social media posts that claimed the phenomenon was seen in Thailand in February 2025. They told AFP the Moon reflects light from the Sun and can be fully illuminated only when they are on opposite sides of the sky.
“#UnbelievableAstronomicalPhenomenon! The Sun and Moon meet on the horizon,” reads a Thai-language Facebook post published on February 17, 2025.
The caption goes on to say: “This scene was captured at the Patong Beach in Phuket, Thailand, where the two celestial bodies appeared side by side over the horizon.”
The post shares an image showing two bright objects slightly above the horizon at the same time.
Screenshot of the false post, taken on February 25, 2025
The same image has been shared by social media users in Thailand claiming it shows an “unbelievable phenomenon” seen at the kingdom’s popular beach.
However, astronomers told AFP the claim is impossible in real life.
“The claim that the Sun and the full Moon met on the horizon over Patong Beach is astronomically impossible,” Matipon Tangmatitham, an astrophysicist at National Astronomical Research Institute (NARIT), told AFP on February 25.
Matipon — who is also the director of UNESCO’s International Training Centre in Astronomy — explained the Moon only reflects sunlight and does not emit light on its own.
He went on to say if the Sun and Moon appear close together, the Moon will be a thin crescent or completely invisible.
This contradicts the bright full Moon as shown in the image — which only happens when it is positioned directly opposite to the Sun in the sky.
“As a result of Thailand’s location near the Earth’s equator, it is not possible for the Sun and Moon to appear parallel to each other along the horizon.”
Matipon also noted that while the image does not appear to be AI-generated, the two objects in the photo are likely not the Sun and the Moon.
“The two bright objects are not bright enough to be the Sun and the Moon and could actually be light sources from another origin, such as a ship, a lighthouse, or other artificial lighting,” Matipon said.
NARIT addressed the viral claim in a Facebook post on February 24 — stating that such a celestial phenomenon was not possible (archived link).
A Google reverse image search found the same photo circulating online since at least January 2022, when it was falsely claimed to depict the Sun and Moon “meeting” in the Strait of Magellan.
José Luis Hormaechea, chief astronomer at the RÃo Grande Astronomical Station in Argentina, told AFP at the time that a full Moon can only be visible when it is positioned directly opposite the Sun in the sky.
“Sun and Moon are almost diametrically opposed — a necessary condition for the Sun to completely illuminate the side of the Moon facing Earth. There is no other possibility,” Hormaechea said. “When one rises, the other sets.”
