𝐂𝐨𝐧𝐬𝐞𝐪𝐮𝐞𝐧𝐜𝐞𝐬 𝐟𝐨𝐫 𝐝𝐞𝐭𝐞𝐫𝐦𝐢𝐧𝐢𝐧𝐠 𝐩𝐫𝐚𝐲𝐞𝐫 𝐭𝐢𝐦𝐞𝐬 𝐢𝐧𝐜𝐥𝐮𝐝𝐞 𝐤𝐧𝐨𝐰𝐢𝐧𝐠 𝐰𝐡𝐞𝐧 𝐭𝐨 𝐬𝐭𝐨𝐩 𝐩𝐫𝐚𝐲𝐢𝐧𝐠 𝐅𝐚𝐣𝐫, 𝐰𝐡𝐞𝐧 𝐭𝐨 𝐛𝐞𝐠𝐢𝐧 𝐌𝐚𝐠𝐡𝐫𝐢𝐛, 𝐚𝐧𝐝 𝐭𝐡𝐞 𝐜𝐨𝐫𝐫𝐞𝐜𝐭 𝐭𝐢𝐦𝐞 𝐭𝐨 𝐛𝐫𝐞𝐚𝐤 𝐭𝐡𝐞 𝐟𝐚𝐬𝐭.

The main purpose of this post is to share a real observation of an early sunrise, along with proof. I also want to explain why this happens and discuss the problems and misunderstandings related to using standard sunrise and sunset times. This is important because it affects when we should stop praying Fajr and when to start Maghrib prayer, which is also the time to break the fast.

I chose this sunrise observation to highlight the issue because Muslims generally (not all though) tend to add extra minutes for Maghrib prayers, but often don’t subtract the time for ending Fajr prayers, when the issue of refraction exists the same way at both times.

𝐒𝐜𝐢𝐞𝐧𝐜𝐞:

When light travels from an area of one density to another, it changes direction; the light refracts (bends), and this is called refraction. This refraction causes the apparent position of the object to shift from where it actually is.

The sun continuously produces light. At sunrise and sunset, the sun is near the horizon at a lower altitude; at this time, the sun’s rays pass through the lower atmosphere before reaching the observer on the Earth. Also, the atmosphere is not uniform, and it gets denser with lower altitude.

At sunrise and sunset, the sun rays travel from the vacuum of outer space into a much denser lower atmosphere, causing light direction to change and refract (bending light). This Atmospheric Refraction during sunrise and sunset shifts the apparent position of the sun, making the sun appear higher in the sky than it actually is.

Just keep in mind that the shift cannot be anything wild — even something as small as 0.5° is unusual, roughly the Sun’s apparent full disk size. I’ve never seen refraction cause the entire Sun disc to appear before the calculated time at sunrise or the full disc to remain visible above the horizon after the calculated sunset time.

So the question is, if we know the refraction is the cause behind the shifting apparent position of the sun, then why can’t we just accommodate this and calculate precisely? Please continue reading, as this is not as simple.

The pressure, temperature, humidity, etc are the factors that change the atmosphere’s density. It is understood that the astronomical refraction increases with a decrease in temperature and an increase in pressure. These parameters are not constant throughout the world, for a given location, for every single day and that causes the value of refraction to be different daily.

There are many different mathematical formulas developed to calculate sunrise and sunset times, accommodating the refraction factors, but as explained, it is not constant for every day, so the standard value of refraction is being used in these formulas to calculate sunrise and sunset times. This is how all formal organisations, websites and applications calculate sunrise and sunset times.

However, since the refraction value can differ on some days from the standard accounted value, sometimes the calculated sunrise and sunset times may not match. When refraction is less than the standard value, the sun will become visible after the sunrise time, and when the refraction value is more than the standard value, then the sun will become visible before the calculated time, as is the case in this example. This is the opposite at sunset. I hope it is clear why it is just impossible to calculate the exact sunrise and sunset times for every single day.

𝐅𝐨𝐫𝐦𝐮𝐥𝐚 𝐟𝐨𝐫 𝐜𝐨𝐮𝐧𝐭𝐢𝐧𝐠 𝐒𝐭𝐚𝐧𝐝𝐚𝐫𝐝 𝐒𝐮𝐧𝐫𝐢𝐬𝐞 𝐚𝐧𝐝 𝐒𝐮𝐧𝐬𝐞𝐭 = 𝐒𝐭𝐚𝐧𝐝𝐚𝐫𝐝 𝐑𝐞𝐟𝐫𝐚𝐜𝐭𝐢𝐨𝐧 + 𝐀𝐬𝐬𝐮𝐦𝐞𝐝 𝟎 𝐄𝐥𝐞𝐯𝐚𝐭𝐢𝐨𝐧 𝐃𝐢𝐟𝐟𝐞𝐫𝐞𝐧𝐜𝐞 = 𝐓𝐡𝐞 𝐮𝐩𝐩𝐞𝐫 𝐥𝐢𝐦𝐛 𝐨𝐟 𝐭𝐡𝐞 𝐬𝐮𝐧 𝐝𝐢𝐬𝐤 𝐛𝐞𝐜𝐨𝐦𝐞𝐬 𝐚𝐩𝐩𝐚𝐫𝐞𝐧𝐭 𝐟𝐢𝐫𝐬𝐭 𝐚𝐭 𝐬𝐮𝐧𝐫𝐢𝐬𝐞 𝐚𝐧𝐝 𝐝𝐢𝐬𝐚𝐩𝐩𝐞𝐚𝐫𝐬 𝐥𝐚𝐬𝐭 𝐚𝐭 𝐬𝐮𝐧𝐬𝐞𝐭.

Just also make it clear it is not a rule that every single time you go and see the early sunrise and delay sunset from the calculated time, in fact most of the time you will find that either the sunrise/sunset will happen near the calculated time or you will see sunrise later and sunset earlier than calculated time. However, all these depend on the geographical location and I do have many more scenarios that are much more complex, which I will share when I am ready to share, but this is enough for basic understanding.

𝐄𝐟𝐟𝐞𝐜𝐭 𝐨𝐟 𝐭𝐡𝐞 𝐝𝐢𝐩 𝐨𝐟 𝐭𝐡𝐞 𝐇𝐨𝐫𝐢𝐳𝐨𝐧:

When calculating sunrise and sunset times, it’s assumed that the observer is at sea level and the horizon is flat, with no slopes or obstacles in the sun’s direction. It also assumes that the first part of the sun’s upper edge appears at sunrise and disappears at sunset.

Sometimes, at sunrise or sunset, an observer might be at a high vantage point with a clear view of the sea as the horizon. In such cases, they may see the sunrise much earlier and the sunset much later than the calculated times. This happens because the observer is at a higher elevation, and the sun appears to rise from a lower point (a dip) on the horizon. The difference in timing they see in this case is not due to atmospheric refraction, as some people assume, but because of the slope or dip toward the horizon. In fact, people have reported seeing sunsets delayed by 5 to 7 minutes and mistakenly attributed it to refraction, when it was actually due to this elevation effect. At least, this is what I found when observers provided me with full details of their observations, and they agreed with the conclusion.

So why can’t we just adjust for this dip in the calculations? The reason is that it’s not simple to factor in horizon elevation differences by default when calculating precise sunrise and sunset times for every location and date. The dip and its distance aren’t constant—it changes depending on the observer’s elevation and the surrounding terrain and sometimes it is not a dip but higher and unobstructed. Because of this complexity, standard sunrise and sunset calculations assume a flat surface with zero elevation difference by default. Even if an application allows dip adjustment, it may not be geometrically accurate in some instances across all locations and dates.

𝐂𝐨𝐧𝐜𝐥𝐮𝐬𝐢𝐨𝐧:

In the example observation used here of 2 April 2025, the calculated standard sunrise time by most applications and websites was around 06:30:12, or 06:30 if converted to the nearest whole number. But actually, the sun’s upper disk first appeared 2 minutes and 14 seconds earlier at 06:28:00 instead.

And if one accounts for the elevation dip in this calculation, then this time would be around 06:29:07 (may vary in seconds between different calculations), but again, actually, the sun’s upper disk first appeared 1 minute and 07 seconds earlier at 06:28:00. Also, as explained earlier no application would be giving this time by default and even it gives it is not necessary that would be geometrically fully accurate for every day and location.

This observation demonstrates that, compared to the standard calculated time that includes standard refraction and even when accounting for the dip, which standard sunrise and sunset calculations typically ignore—the Sun can still appear above the horizon before the standard calculated sunrise time and remain visible after the standard sunset time.

𝐍𝐨𝐭𝐞: I’ve been collecting detailed sunrise and sunset data over the past two years with a focused approach. This is the first time I’m sharing my observations specifically about early sunrises and delayed sunsets. I plan to share more of these observations in the future, covering different scenarios, complexities, and comparisons that include delay in sunset too.

𝐐𝐮𝐞𝐬𝐭𝐢𝐨𝐧: I would like to hear your thoughts—and any relevant religious texts you may have—on whether we should consider adjusting the calculated times for Fajr and Maghrib prayers. Specifically, should we stop praying Fajr a few minutes before the pre-calculated sunrise time, and should we delay the start of Maghrib by adding a few minutes after the calculated sunset time?

How many minutes would be appropriate, if any? If your view is against making such adjustments, please share the reasoning, logic, or religious references behind that position.

I understand that there are differing views in Fiqh, with some scholars supporting these time adjustments and others not. I plan to share my own reflections and some additional points in Part 2.