Partial Solar Eclipse Accompanies the Arrival of Eid al-Fitr 1446

A partial solar eclipse will occur on Saturday (29/3/2025) from 3:51 PM WIB to 7:44 PM WIB. This eclipse can only be observed in eastern Canada, the northern Atlantic Ocean, northwestern Africa, most of Europe, and northern Asia. This eclipse cannot be seen in Indonesia.

The peak of the eclipse occurred at 17:47 WIB, when 93 percent of the Sun's disk was covered by the Moon's disk that could be observed in eastern Canada. The peak of this partial solar eclipse occurred 10 minutes before the conjunction or ijtimak which showed the alignment of the Sun, Moon, and Earth.

With the alignment of the Sun, Moon, and Earth during conjunction, a solar eclipse is essentially an observable conjunction. Both conjunctions and solar eclipses will always occur during the new moon phase.

However, this does not mean that after a solar eclipse or conjunction, it automatically starts the new Hijri month.

The conjunction that became the boundary of the end (month) of Ramadhan and the beginning of the month of Syawal 1446 this time occurred on Saturday (29/3) at 17:57 WIB. Many people assume that after the conjunction occurs, automatically after the sun sets it will immediately enter the beginning of a new Hijri month.

The mistaken perspective that became a debate among netizens emerged during the difference in the celebration day of Eid al-Fitr, as occurred in 2023.

The Hijri calendar is an astronomical calendar. Therefore, the indication of the beginning of its months is determined based on the position of the crescent moon, whether it requires the crescent to be observed or simply the existence of the crescent without the need for observational evidence.

The crescent moon, or hilal, is the first ultra-thin crescent formed or visible after sunset following the conjunction. The definition or criteria for the hilal marking the beginning of the Hijri month varies, and there is no single consensus, either within Indonesia or the Islamic world.

The provisions regarding the crescent moon are what differentiate the Islamic calendar from other lunar calendars, which are generally mathematical calendars. In mathematical calendars, the beginning of the month is usually determined to coincide with the moment of the new moon phase or the day of conjunction.

Therefore, in the Hijri calendar, a solar eclipse does not automatically signify the arrival of a new Hijri month. A solar eclipse or conjunction both indicate the beginning of a new Moon phase which is the basis for determining the beginning of a Hijri month.

For those who adhere to determining the beginning of the Hijri month based on rukyat, then when the Sun sets after the conjunction occurs, rukyat or observation of the crescent moon will be carried out. In addition to proving the existence of the crescent moon, this observation is to prove the calculation of the position of the crescent moon that has been done.

In Indonesia, crescent moon observations are carried out in many locations by astronomers from Islamic boarding schools and universities to officers from several government institutions. If the crescent moon is successfully observed in one of the observation locations, tomorrow will enter a new Hijri month. If it is not observed, the age of the current Hijri month will be rounded up to 30 days.

Meanwhile, for those who adhere to the hisab or crescent moon existence method, after the conjunction occurs, the position of the crescent moon will be calculated in relation to other celestial bodies.

This calculation is to ensure that when the Sun sets, the crescent moon is above the horizon and the Sun sets before the Moon. If the crescent moon is still below the horizon and the Moon sets before the Sun, it means that tomorrow is still part of the current Hijri month.

In addition, according to the lecturer of the Atmospheric and Planetary Science Study Program of the Sumatra Institute of Technology Moedji Raharto and quoted by Kompas, April 20, 2023, a solar eclipse is a topocentric phenomenon or one that occurs on the Earth's surface. A solar eclipse can occur around the time of conjunction, either before or after conjunction.

For the past three years, Eid al-Fitr has always coincided with a solar eclipse.

While the crescent moon that marks the beginning of the Hijri month is a geocentric phenomenon, aka the position of the crescent moon is determined from the position of the Sun and Moon from the core or center of both. Thus, when viewed from the Earth's surface at sunset, the crescent moon will have a certain height and elongation, aka angular distance.

Therefore, the occurrence of a solar eclipse and the beginning of the Hijri month almost simultaneously is natural considering that the two events both refer to the same phenomenon, namely the alignment of the Sun, Moon, and Earth. However, it does not mean that after a solar eclipse or conjunction, it automatically immediately enters the beginning of a new Hijri month.

However, a solar eclipse does not occur at every conjunction. This situation is triggered by the Moon's orbital plane around the Earth not overlapping with the Earth's orbital plane around the Sun.

The Moon's orbital plane is tilted 5 degrees to the Earth's orbital plane. A solar eclipse will only occur during conjunction if the Moon's ecliptic latitude is between 0-1 degrees. If the Moon's ecliptic latitude during conjunction reaches 1-5 degrees, then a solar eclipse will not occur.

For the past three years, Eid al-Fitr has always coincided with a solar eclipse. However, only Eid al-Fitr and the 2023 solar eclipse caused debate on social media considering that at that time there was a difference in Eid al-Fitr days in Indonesia.

Eid al-Fitr 1444/2023 coincides with a hybrid solar eclipse on April 20, 2023, which can be observed from Maluku and Papua. The government has set Eid al-Fitr 1444 on April 22, 2023, while residents who use hisab celebrate Eid on April 21, 2023 or the day before. The difference in this holiday is due to the fact that the definition of the hilal used is not yet uniform.

Next is Eid al-Fitr 1445/2024 which occurs simultaneously with the total solar eclipse on April 9, 2024 which can be witnessed in North America. At that time there was also a super new moon event which took place when the Moon was at its closest distance to Earth.

At that time, Eid al-Fitr 1445 in Indonesia was celebrated simultaneously on April 10, 2024, both using rukyat or hisab in determining the beginning of the Hijri month.

Lastly, Eid al-Fitr 1446/2025 coincides with a partial solar eclipse on March 29, 2025. Most likely, Eid al-Fitr in Indonesia will coincide with that set by the government, namely Monday, March 31, 2025. However, this decision will still await the results of the crescent observation and the isbat session which will be held on Saturday (29/3) evening.

The similarity of Eid al-Fitr 1446/2025 occurred after the position of the crescent moon on Saturday (29/3) or 30 Ramadhan 1446 both did not meet the criteria for determining the beginning of the Hijri month used by hisab or rukyat practitioners.

Because the conjunction occurred on Saturday (29/3) at 17.57 WIB, then the sunset or Maghrib on Saturday evening will be the basis for determining the beginning of the Hijri month.

Based on data from the Meteorology, Climatology and Geophysics Agency, the position of the crescent moon in Indonesia on Saturday evening ranged from minus 3.29 degrees in Merauke, South Papua to minus 1.07 degrees in Sabang, Aceh.

This means that the crescent moon on Saturday evening is still below the horizon. With this condition, the crescent moon is certain not to be observed or sighted. In terms of calculations, the negative crescent height has not met the criteria for the beginning of the Hijri calendar month which requires the crescent moon to be above the horizon.

Meanwhile, the elongation or angular distance of the Moon-Sun on Saturday (29/3) evening reached 1.06 degrees in Kebumen, Central Java to 1.61 degrees in Oksibil, Papua Mountains.

This geocentric elongation value is much smaller than the minimum elongation limit used in the new MABIMS (Ministry of Religious Affairs of Brunei Darussalam, Indonesia, Malaysia, and Singapore) criteria which requires the crescent moon to be observed if its elongation is at least 6.4 degrees.

Although Eid al-Fitr 1446/2025 will most likely be celebrated by Indonesian Muslims together, there is the potential for differences in Eid al-Fitr with Arab countries or countries in the western hemisphere.

Too small elongation makes the Moon's position still too close to the Sun so that it is difficult to separate its light. This is because the position of the Sun and Moon are in a line when the conjunction occurs.

Thus, in terms of elongation, the crescent moon on Saturday (3/29) evening is also impossible to observe. Moreover, the position of the crescent moon is still below the horizon so that both in terms of height and elongation, the crescent moon is truly unobservable.

Since the crescent moon cannot be observed on Saturday evening, the isbat session on Saturday (3/29) night will likely set the age of the month of Ramadan to 30 days because the age of the month in the Hijri calendar can only be 29 days or 30 days. So, Eid al-Fitr 1 Shawwal 1446/2025 has the potential to fall on Monday, March 31, 2025.

Although Eid al-Fitr 1446/2025 will most likely be celebrated by Indonesian Muslims simultaneously, there is a potential for differences in Eid al-Fitr with Arab countries or countries in the western hemisphere. The certainty awaits from the observation of the crescent moon in each country.

Whatever the outcome, happy Eid al-Fitr 1446/2025. Please accept our apologies, may happiness always be with us all.