The town of Kawaihae sits on the northwest coast of the island of Hawai'i. Being a major port for the island, it contributes some low pressure sodium light as seen from the summit. It appears to also feature some continuum lighting, high pressure sodium or metal halide. The town of Waikoloa is partially obscured by the slope of Mauna Kea, but its own lights are almost solely low pressure sodium streetlamps.
In the distance, about 320 km (200 miles) away, is the city of Honolulu. The glow from the lights of a city of about one million inhabitants is clearly visible in the sky. This glow, on the edge of naked eye visibility on a normal night at the summit, is here enhanced by the twenty-minute exposure. It is unclear if, in exceptionally clear conditions, lights in Honolulu would be directly seen from Mauna Kea.
The domes of the Keck II telescope and NASA's IRTF dominate the left side of the image. The image of these was taken during bright moonlight, which can be seen reflecting off both of the domes. The highly reflective surface of IRTF casts a bright spectrum of the moon, while the white-painted Keck dome gives a fainter spectral reflection.