New! Sign up for our free email newsletter.
Reference Terms
from Wikipedia, the free encyclopedia

Antarctic Circle

The Antarctic Circle is one of the five major circles or parallels of latitude that mark maps of the Earth. It is at latitude 66 degrees 33′ 39″ south of the equator (in 2000; like its northern counterpart, the Arctic Circle, the value is currently slowly decreasing over time, pushing the Antarctic Circle southwards with about 15 m per year). For everywhere within the Antarctic Circle, there is at least twenty-four hours of continuous daylight on the Summer Solstice in December, and at least twenty-four hours of continuous nighttime on the Winter Solstice in June. That is to say, one whole day during which the sun does not set, and one whole day during which the sun does not rise. This is because the earth is tilted at a 23.5 degree angle, and during the winter solstice, the southern hemisphere is tilted away from the Sun, meaning that the antarctic circle is completely tilted away from the Sun, hence it experiences 24 hour nighttime, and vice versa.

Related Stories
 


Earth & Climate News

February 27, 2026

Antarctica’s Hektoria Glacier stunned scientists by retreating eight kilometers in just two months, with nearly half of it collapsing in record time. The rapid breakup was driven by a flat, underwater bedrock surface that allowed the glacier to ...
A lost cache of 250-million-year-old fossils from Australia has rewritten part of the story of life after Earth’s worst mass extinction. Instead of a single marine amphibian species, researchers ...
Scientists have proposed a surprising connection between solar flares and earthquakes. When solar activity disturbs the ionosphere, it may generate electric fields that penetrate fragile fracture zones in Earth’s crust. If a fault is already ...
Deep in the Congo Basin, vast peatlands quietly store enormous amounts of Earth’s carbon — but new research suggests this ancient vault may be leaking. Scientists studying Africa’s largest ...
A new 30-year analysis reveals that melting land ice is now the main force behind rising global sea levels. Researchers discovered that oceans rose about 90 millimeters since 1993, with most of the increase coming from added water mass rather than ...
Deep in the Arctic north, drained peatlands—once massive carbon vaults built over thousands of years—are quietly leaking greenhouse gases into the atmosphere. But new field research from northern Norway suggests there’s a powerful way to slow ...
Flea and tick medications trusted by pet owners worldwide may have an unexpected environmental cost. Scientists found that active ingredients from isoxazoline treatments pass into pet feces, exposing dung-feeding insects to toxic chemicals. These ...
Ocean waves are a vast and steady source of renewable energy, but capturing their power efficiently has long frustrated engineers. A researcher at The University of Osaka has now explored a bold new approach: a gyroscopic wave energy converter that ...
As the planet warms, many expected ecosystems to change faster and faster. Instead, a massive global study shows that species turnover has slowed by about one-third since the 1970s. Nature’s constant reshuffling appears to be driven more by ...
NASA has pulled off a high-flying aurora investigation, launching three rockets into the glowing northern lights over Alaska. One mission targeted mysterious dark patches called black auroras, while ...
For years, satellite data suggested that autumn snow cover in the Northern Hemisphere was actually increasing — a surprising twist in a warming world. But a new analysis reveals that this apparent growth was an illusion caused by improving ...
Even Antarctica’s toughest native insect can’t escape the reach of plastic pollution. Scientists have discovered that Belgica antarctica — a tiny, rice-sized midge and the southernmost insect on Earth — is already ingesting microplastics in ...

Latest Headlines

updated 12:56 pm ET