Reference Terms
from Wikipedia, the free encyclopedia
Axial tilt
Axial tilt is an astronomical term regarding the inclination angle of a planet's rotational axis in relation to a perpendicular to its orbital plane. It is also called axial inclination or obliquity. The axial tilt is expressed as the angle made by the planet's axis and a line drawn through the planet's center perpendicular to the orbital plane.
The axial tilt may equivalently be expressed in terms of the planet's orbital plane and a plane perpendicular to its axis. In our solar system, the Earth's orbital plane is known as the ecliptic, and so the Earth's axial tilt is officially called the obliquity of the ecliptic.
The Earth has an axial tilt of about 23 degrees 27’. The axis is tilted in the same direction throughout a year; however, as the Earth orbits the Sun, the hemisphere (half part of earth) tilted away from the Sun will gradually come to be tilted towards the Sun, and vice versa. This effect is the main cause of the seasons (see effect of sun angle on climate). Whichever hemisphere is currently tilted toward the Sun experiences more hours of sunlight each day, and the sunlight at midday also strikes the ground at an angle nearer the vertical and thus delivers more heat.
Related Stories
1
2
Earth & Climate News
November 4, 2026
Oct. 29, 2026 Earth is warming faster than ever recorded, with scientists detecting a major acceleration in global temperatures since around 2015. A new study reveals that the warming rate has surged to approximately 0.35°C per decade, nearly double the average ...
Oct. 29, 2026 Ancient ice discovered high in Tibet may be more than 128,000 years old, preserving an extraordinary record of Earth's climate that scientists previously thought had been lost. The discovery reveals a rare glimpse into the last ice age and could ...
Oct. 28, 2026 Scientists have uncovered a surprising connection between Earth's opposite poles that may help explain how the planet plunged into past ice ages. New research suggests that as massive ice sheets expanded across the Northern Hemisphere, they cooled ...
Oct. 28, 2026 Antarctica’s Thwaites Glacier may be melting twice as much as previously predicted, even without additional global warming. Scientists discovered that warm ocean water is penetrating miles beneath ...
Oct. 26, 2026 Arctic winter sea ice could disappear much faster than scientists previously expected, according to new research using climate clues from 6,000 years ago. By comparing ancient ocean sediments with modern climate models, researchers found that future ...
Oct. 23, 2026 Switzerland’s glaciers are disappearing at an alarming rate, losing more than 5% of their ice volume in 2026 alone. Some of the country’s most famous glaciers experienced their worst melting on record, while several smaller glaciers vanished ...
Oct. 22, 2026 Forty years after the Chornobyl disaster, tiny radioactive particles still linger in the soil, carrying a dangerous legacy. Using powerful X-rays, scientists discovered that some of these particles have remained surprisingly stable, trapping ...
Oct. 22, 2026 Honeybees are aggressively pushing wild pollinators away from flowers, with scientists documenting how they chase off rivals and dominate valuable food sources. New research warns that rising temperatures and increasing honeybee populations could ...
Oct. 21, 2026 Scientists have cracked a 178-year-old mystery surrounding a train delayed by a solar storm, revealing that the famous incident happened in 1848 rather than 1841. The discovery rewrites the early history of space weather and highlights a threat that ...
Oct. 20, 2026 A new study reveals that improved hurricane forecast graphics may help people identify threatened areas without making them more likely to recognize the danger or take protective action. Researchers also found that a widespread misunderstanding of ...
Oct. 19, 2026 A massive landslide in Alaska triggered the second-highest tsunami ever recorded, sending water and debris 1,580 feet up a mountainside just hours after tourists visited the area. Scientists discovered that the disaster was preceded by several ...
Oct. 19, 2026 Scientists have discovered evidence of two hidden magma sources beneath Nicaragua’s Masaya volcano, where satellite observations revealed mysterious ground movements suggesting magma is shifting deep underground. The findings could improve ...
Latest Headlines
updated 12:56 pm ET
Nov. 2, 2026 NASA satellites have captured an eerie, skull-shaped formation on a remote Antarctic island, but its haunting appearance conceals a troubling warning about melting glaciers. Unusually warm winter ...
Oct. 30, 2026 Scientists may have solved a 66-million-year-old mystery: how crocodiles survived the asteroid that wiped out the dinosaurs. A sweeping analysis of fossils and ancient climates suggests that their ...
Oct. 28, 2026 Scientists have discovered that magma deep inside Earth can store surprising amounts of extra oxygen, potentially revealing a hidden contributor to our planet's oxygen-rich atmosphere. The findings ...
Oct. 28, 2026 Scientists have uncovered a long-lost volcanic system in Iran that dates back roughly 100 million years, revealing a hidden chapter in Earth's tectonic history. The discovery sheds new light on the ...
Oct. 26, 2026 A solar eclipse recorded more than 2,700 years ago is revealing surprising secrets about Earth's rotation and the Sun's ancient behavior. By ...
Oct. 23, 2026 Deep beneath Japan’s Kikai caldera, a massive magma reservoir is refilling 7,300 years after one of the most powerful volcanic eruptions in Earth's recent geological history. Scientists used ...
Oct. 21, 2026 Scientists discovered a rock in Papua New Guinea that plunged more than 90 kilometers beneath Earth's surface, revealing a bizarre temperature pattern that challenges established theories of Earth's ...
Oct. 21, 2026 A decades-long mystery beneath the North Sea has finally been solved. Scientists have confirmed that the Silverpit Crater, buried 700 meters below ...
Oct. 19, 2026 Scientists have discovered that severely bleached corals can make a remarkable comeback simply by touching healthy, genetically identical corals. In laboratory experiments, dying corals regained ...
Oct. 18, 2026 A catastrophic volcanic eruption 7,300 years ago devastated Japan, but new research reveals that its impact on prehistoric populations was far more ...