Why Jakarta’s Sky Turned Pink Yesterday Afternoon: Was Pollution Involved?

A photograph showing Jakarta’s sky turning pink on Tuesday afternoon (27 October) went viral. The Meteorology, Climatology and Geophysics Agency (BMKG) said the phenomenon was caused by the refraction and scattering of light.

Marjuki, director of applied climate services at BMKG, said it occurred shortly before sunset. With the sun low in the sky, its rays had to travel much farther through the atmosphere before reaching the eye.

Short-wavelength blue light was scattered earlier, leaving the longer-wavelength red and orange light. At the same time, high humidity and a layer of fine particles in the atmosphere acted like a giant reflective screen.

“This layer in the upper atmosphere scatters red and orange light in all directions. When the red glow combines with the remaining refracted blue light in the upper sky, the spectrum perceived by the eye appears as a gradient from pink to purple,” Marjuki said in a statement on Wednesday (28 October 2026).

BMKG said Jakarta’s air quality remained under control. The agency said the colour of the sky at a particular altitude could not be used as a direct measure of the quality of the air people breathe at ground level.

“Based on BMKG monitoring data for PM2.5 particulate concentrations at Kemayoran Station during the phenomenon, readings ranged from 30 to 39 µg/m³, which is classified as moderate,” it said.

“These measurements were relatively stable and were even lower than concentrations recorded in the morning. This confirms that the pink glow was purely the result of optical interactions in the upper atmosphere, and was not caused by an extreme rise in pollution at ground level,” it said.

The public was urged to continue their normal activities and not be alarmed by worrying reports.