Astronomical spring begins on Friday, March 20th at 3:46 PM, promising bright planets, conjunctions, and potentially comets in the night sky.
Astronomical Spring Begins
Winter will officially end on Friday, March 20th at 3:46 PM with the arrival of the vernal equinox, marking the start of astronomical spring.
During this season, observers can expect to see bright planets, spectacular conjunctions, and possibly even comets visible to the naked eye.
The Equinox and Earth’s Tilt
The exact moment of the vernal equinox occurs when the Sun passes through the “Aries point,” or the vernal equinox point. Spring will last until the summer solstice on June 21st at 10:25 AM.
Astronomical seasons are defined by the moments when the Sun reaches its highest point in the sky above the equator or the tropics. This corresponds to specific positions of the Sun on the ecliptic, its apparent path against the backdrop of stars.
Daylight and the Tropics
During the vernal equinox, the Sun is directly overhead at the equator. From this point onward, days become longer than nights in the Northern Hemisphere (and vice versa in the Southern Hemisphere).
The farthest parallels from the equator over which the Sun can be directly overhead are called the tropics. For the Northern Hemisphere, this is the Tropic of Cancer. The Sun being overhead at this point marks the summer solstice, signifying the end of spring and the beginning of summer.
Celestial Coordinate Systems
Beyond the ecliptic, astronomy utilizes another coordinate system based on the celestial equator and poles. The celestial equator is an extension of Earth’s equator into space.
Earth’s axis of rotation is tilted relative to the plane of the ecliptic, and consequently, the plane of the celestial equator is also tilted. The celestial equator and ecliptic intersect at two points: the Aries point and the Libra point. When the Sun’s apparent position falls at these points, we experience the vernal (March) and autumnal (September) equinoxes.
The Shifting Aries Point
Interestingly, the Aries point is no longer located within the constellation Aries. It shifted out of the constellation in the first century AD and is currently in Pisces.
The Aries point drifts against the backdrop of constellations due to changes in Earth’s axis of rotation, a phenomenon called precession. The axis completes a full circle over 25,800 years. Calculations indicate the Aries point will enter Aquarius in 2597.
Planetary and Lunar Events This Spring
This spring offers several interesting astronomical events, with warmer temperatures making evening skywatching more pleasant.
Jupiter will be particularly bright in the night sky, notably on the night of March 20th-21st, appearing high in the sky near the Orion and Gemini constellations, with contributions from Procyon in Canis Minor and Sirius.
Conjunctions and Meteor Showers
Jupiter will have a spectacular conjunction with the Moon on March 25th and 26th, with several more conjunctions throughout the spring (April 23rd, May 20th, and June 17th).
The Lyrid meteor shower peaks on the night of April 22nd-23rd, potentially offering up to 18 meteors per hour. The Eta Aquariids peak on May 6th, with a theoretical maximum of 60 meteors per hour.
Comets and Full Moons
Comets C/2026 A1 (MAPS) and C/2025 R3 (PanSTARRS) may be visible to the naked eye in April, depending on their survival after passing near the Sun. C/2026 A1 may be a fragment of a comet from 371 BC, known as Aristotle’s Comet.
Full moons will occur on April 2nd, May 1st, and May 31st, with new moons on April 17th, May 16th, and June 15th.
Cosmic Anniversaries
Several cosmic anniversaries fall during spring. International Earth Day is observed on March 22nd, and International Day of Human Space Flight is celebrated on April 12th, often marked by “Yuri’s Night” events honoring Yuri Gagarin’s first human spaceflight in 1961.
International Dark Sky Week begins on April 13th, International Astronomy Day is on April 25th, and International Day of Light is on May 16th.