# Photic Zone

> From sunlight at the surface to the darkness of the deep sea.

- Field: Geology
- Level: Intermediate
- Qur'an passage: Quran 24:40
- URL: https://dailymuslim.org/quran-miracles/photic-zone-ocean-darkness

Adapted from Miracles of Quran, with independently checked scientific context.

A sunlit sea can hide a dark world below. The source article connects the fading of light in the ocean with the layered darkness described in Quran 24:40. Understanding how light changes with depth makes this reflection more precise.

NOAA describes a sunlit zone roughly within the upper 200 metres, a twilight zone extending to about 1,000 metres, and a deeper zone without sunlight. These are approximate divisions: water clarity and local conditions affect light penetration. The 200-metre boundary is not a universal limit of unaided human vision.

### Additional evidence — research summaries

> Water absorbs colours unevenly, with red light absorbed more readily than blue light. Suspended particles also affect the colour we see. The sea therefore filters incoming sunlight rather than simply becoming dark at a single fixed depth.

— [NOAA — why the ocean is blue](https://oceanservice.noaa.gov/facts/oceanblue.html)

### Additional evidence — research summaries

> An absence of sunlight does not mean an absence of every light source. Some marine organisms produce their own light through chemical reactions, a phenomenon called bioluminescence.

— [NOAA Ocean Exploration — bioluminescence](https://oceanexplorer.noaa.gov/ocean-fact/bioluminescence/)

## Qur'an passage · Quran 24:40

٤٠ أَوْ كَظُلُمَاتٍ فِي بَحْرٍ لُجِّيٍّ يَغْشَاهُ مَوْجٌ مِنْ فَوْقِهِ مَوْجٌ مِنْ فَوْقِهِ سَحَابٌ ۚ ظُلُمَاتٌ بَعْضُهَا فَوْقَ بَعْضٍ إِذَا أَخْرَجَ يَدَهُ لَمْ يَكَدْ يَرَاهَا ۗ وَمَنْ لَمْ يَجْعَلِ اللَّهُ لَهُ نُورًا فَمَا لَهُ مِنْ نُورٍ

*Meaning in our own words: Or like darkness in a deep sea, covered by a wave, above which is another wave, with clouds above. Darkness lies in layers; a person holding out a hand can scarcely see it. Whoever Allah does not grant light has no light.*

### Reading the verse in context — summary

> Quran 24:39–40 uses a mirage and deep darkness as parables. Ibn Kathir explains the darkness in relation to disbelief and the need for Allah’s guidance. The scientific connection offered here is a modern reflection; it does not establish that the verse specifies an oceanographic mechanism or that the phenomenon was unknown in antiquity.

— [Quran.com — Ibn Kathir, commentary on 24:39–40](https://quran.com/an-nur/40/tafsirs/en-tafisr-ibn-kathir)

The verse’s image of a hand barely visible in deep darkness invites reflection on our dependence on light and guidance. Ocean science helps us appreciate this physical setting, while the verse’s message reaches beyond a description of seawater.

## Ponder

**What does this movement from light into darkness invite us to reflect on?**

## Sources and further reading

- [Quran 24:40 · Quran.com](https://quran.com/24/40)
- [NOAA — how far light travels in the ocean](https://oceanservice.noaa.gov/facts/light_travel.html)
- [Miracles of Quran](https://www.miracles-of-quran.com/photic_zone.html)

— Miracle of Quran, Daily Muslim · https://dailymuslim.org/quran-miracles/photic-zone-ocean-darkness