Shadow-Free Day Coming Next Week, Here Are the Dates and Locations
Jakarta - BMKG has predicted that shadow-free days will occur in several regions of Indonesia in late February 2026. Where and when will they happen?
As quoted from the official BMKG website on Sunday (2/15/2026), shadow-free days will occur at different times across various regions in Indonesia. A shadow-free day, or primary culmination, occurs when the sun is directly above the observer’s head, or at the zenith point.
“As a result, the shadow of an upright object will appear to ‘disappear’ because it overlaps with the object itself. That is why the primary culmination day is also known as a shadow-free day,” BMKG said.
BMKG explained that this condition occurs because the Earth’s equatorial plane, or the plane of Earth’s rotation, does not exactly coincide with the ecliptic plane, or the plane of Earth’s revolution. As a result, the sun’s position as seen from Earth appears to continuously change throughout the year.
“This year, the sun will be directly above Pontianak City on March 20, 2026, at 11:50 AM WIB and September 23, 2026, at 11:35 AM WIB. On June 21, 2026, at 3:25 PM WIB, the sun will be at the northern solstice, and on December 22, 2026, at 3:49 AM WIB, the sun will be at the southern solstice,” BMKG said.
BMKG said Indonesia’s location near the equator means primary culmination in Indonesian territory occurs twice a year, not far from the time the sun is at the equator. In other cities, primary culmination occurs when the sun’s declination equals the city’s latitude.
“In general, the 2026 primary culmination in Indonesia occurs between February 21, 2026, in Baa, East Nusa Tenggara, and April 5, 2026, in Sabang, Aceh, and from September 7, 2026, in Sabang, Aceh, to October 21, 2026, in Baa, East Nusa Tenggara,” BMKG said.
Here is the schedule of shadow-free days in various cities across Indonesia:
- Banda Aceh: April 4, 2026, at 12:41:46 PM WIB
- Medan: March 29, 2026, at 12:30:04 PM WIB
- Padang: March 18, 2026, at 12:26:39 PM WIB
- Pekanbaru: March 21, 2026, at 12:21:08 PM WIB
- Bengkulu: March 11, 2026, at 12:21:00 PM WIB
- Jambi: March 16, 2026, at 12:14:15 PM WIB
- Tanjung Pinang: March 23, 2026, at 12:08:52 PM WIB
- Palembang: March 13, 2026, at 12:10:28 PM WIB
- Bandar Lampung: March 7, 2026, at 12:10:00 PM WIB
- Pangkal Pinang: March 15, 2026, at 12:04:31 PM WIB
- Serang: March 5, 2026, at 12:06:53 PM WIB
- Central Jakarta: March 5, 2026, at 12:04:11 PM WIB
- Bandung: March 3, 2026, at 12:01:31 PM WIB
- Semarang: March 3, 2026, at 11:50:10 AM WIB
- Yogyakarta: February 28, 2026, at 11:51:04 AM WIB
- Surabaya: March 2, 2026, at 11:41:18 AM WIB
- Pontianak: March 20, 2026, at 11:50:11 AM WIB
- Palangka Raya: March 15, 2026, at 11:33:24 AM WIB
- Banjarbaru: March 12, 2026, at 12:30:29 PM WITA
- Samarinda: March 19, 2026, at 12:19:21 PM WITA
- Tanjungselor: March 28, 2026, at 12:15:41 PM WITA
- Denpasar: February 26, 2026, at 12:32:03 PM WITA
- Mataram: February 26, 2026, at 12:28:30 PM WITA
- Kupang: February 22, 2026, at 11:59:10 AM WITA
- Mamuju: March 14, 2026, at 12:13:42 PM WITA
- Makassar: March 7, 2026, at 12:13:23 PM WITA
- Palu: March 18, 2026, at 12:08:42 PM WITA
- Kendari: March 10, 2026, at 12:00:15 PM WITA
- Gorontalo: March 22, 2026, at 11:54:42 AM WITA
- Manado: March 24, 2026, at 11:46:59 AM WITA
- Sofifi: March 22, 2026, at 12:36:43 PM WIT
- Ambon: March 11, 2026, at 12:37:21 PM WIT
- Sorong: March 18, 2026, at 12:23:00 PM WIT
- Manokwari: March 18, 2026, at 12:11:50 PM WIT
- Jayapura: March 14, 2026, at 11:46:28 AM WIT
- Nabire: March 12, 2026, at 12:07:49 PM WIT
- Wamena: March 10, 2026, at 11:54:33 AM WIT
- Merauke: February 27, 2026, at 11:51:08 AM WIT