Discover what time dawn begins and understand astronomical phenomena

Have you ever wondered what time dawn begins in your region? Knowing the exact moment the Sun rises over the horizon is not just an astronomical curiosity but practical information that helps organize daily activities, plan hikes, fishing trips, agricultural work, and appreciate one of the most beautiful natural spectacles of the day.

Factors that determine the exact time of dawn

The time when dawn begins is not the same every day or everywhere on Earth. Several fundamental factors influence this natural phenomenon:

Geographic latitude plays a decisive role. Near the Equator, seasonal time variations are minimal, while at mid-latitudes like Argentina, there can be differences of up to two hours between summer and winter solstices. The farther from the Equator toward the poles, the more extreme these variations become.

Earth’s axial tilt is another critical factor. This tilt of about 23.5 degrees relative to its orbital plane causes, during the southern hemisphere’s summer, dawn to occur significantly earlier than in winter. This cycle repeats annually, creating predictable patterns of sunrise timing variations.

The time of year also directly affects dawn. Data from the Naval Hydrographic Service (SHN) show that in a city like Buenos Aires, dawn varies considerably throughout the months, being earlier in December and later in June.

Morning twilight and sunrise: key differences

Many people confuse the moment dawn begins with the actual sunrise. However, there are important differences:

Morning twilight is the period of partial brightness that occurs just before the Sun rises. During this time, the Sun is still below the horizon, but its rays scatter in the Earth’s atmosphere, gradually illuminating the sky. According to SHN, in Buenos Aires, this phenomenon begins around 6:01 a.m. during winter days.

Sunrise is the precise moment when the upper edge of the solar disk emerges above the horizon. This marks the technical start of the day and the definitive transition from night to daylight. SHN records that sunrise occurs approximately at 6:27 a.m.

Between the start of morning twilight and the actual sunrise, typically 20 to 30 minutes pass—a interval that varies depending on the time of year and geographic location.

Day’s maximum temperature and its relation to the solar cycle

Once dawn begins and the Sun rises in the sky, temperatures start to increase. However, the hottest moment does not coincide with sunrise but occurs hours later.

The National Meteorological Service (SMN) and specialized platforms like Windy agree that the daily maximum temperature is usually recorded in the early afternoon, around 4:00 p.m. In a typical winter day, this maximum can reach 26°C in Buenos Aires.

This delay between sunrise and peak temperature is due to the Earth’s atmosphere needing time to accumulate solar energy and transfer it as heat. The maximum is reached when the accumulated solar radiation during hours of exposure attains its highest intensity.

Sunset and evening twilight

Just as dawn marks the start of the day, sunset signals its end. SHN indicates that sunset occurs around 7:46 p.m., when the upper edge of the solar disk disappears below the horizon.

After sunset, the evening twilight begins, which is the period of partial sky illumination after sunset. During this time, the Sun remains below the horizon but its light continues scattering in the atmosphere, creating a gradual transition to night. SHN records that this final twilight ends around 8:13 p.m.

Summary of solar cycle timings:

• Morning twilight: 6:01 a.m.
• Sunrise: 6:27 a.m.
• Maximum temperature: 4:00 p.m.
• Sunset: 7:46 p.m.
• Evening twilight: until 8:13 p.m.

Notable astronomical events of 2026

The year 2026 promises to be especially interesting for skywatchers. According to data from SHN and NASA, four major eclipse events will occur:

An annular solar eclipse is scheduled for February 17, visible as an annular phase from Antarctica and partially visible from southern Argentina and Chile.

On March 3, a total lunar eclipse will be visible across the Americas, including Argentina, eastern Asia, Australia, and the entire Pacific Ocean. During this event, the Moon will take on the characteristic reddish hue known as the “Blood Moon.”

A total solar eclipse will occur on August 12, with the total phase visible from the Arctic, Greenland, Iceland, and Spain.

Finally, on August 28, a partial lunar eclipse will be visible across the Americas, including Argentina, Europe, Africa, and the eastern Pacific.

Understanding eclipse types

Solar and lunar eclipses operate differently. In an annular solar eclipse, the Moon is positioned between Earth and the Sun but is far enough in its orbit not to completely cover the Sun, leaving a spectacular “ring of fire” around the lunar edge. The sky remains bright during this event, and special eclipse glasses are required for safe viewing.

A total lunar eclipse occurs when Earth completely blocks sunlight from reaching the Moon, casting its darkest shadow on the satellite. This phenomenon, visible to the naked eye, tints the Moon reddish due to the refraction of sunlight through Earth’s atmosphere.

In a total solar eclipse, the Moon aligns perfectly between Earth and the Sun, fully covering the solar disk from a narrow band called the path of totality, where the day darkens as at dusk, revealing the solar corona.

A partial lunar eclipse happens when only part of the Moon enters Earth’s darkest shadow, creating a partially illuminated and reddish-toned Moon.

Meteor showers and astronomical events of 2026

Beyond eclipses, 2026 will feature multiple meteor showers for astronomy enthusiasts. According to NASA data, the most notable are:

The Quadrantids, observable from late December to early January, are among the year’s most intense showers.

The Lyrids appear in late April, offering the chance to see dozens of meteors per hour.

The Eta Aquarids occur from late April to early May, remnants of the famous Halley’s Comet.

The Delta Aquarids and Perseids occur between late July and early August, providing two opportunities for observation in a short period.

The Orionids light up the sky from early October to mid-November.

The Leonids appear from early to late November, known for producing spectacular meteor storms.

Finally, the Geminids peak in December, being one of the brightest and most abundant meteor showers of the year.

Knowing these astronomical phenomena and understanding how they occur not only enriches our appreciation of the universe but also connects us with natural cycles that have guided humanity since time immemorial.