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Today's featured article

Habitable zones of TRAPPIST-1 and the Solar System

TRAPPIST-1 is a cool red dwarf star with seven known exoplanets. It lies in the constellation Aquarius about 40.66 light-years away from Earth. It has a mass of about 9% of the Sun and is estimated to be 7.6 billion years old, making it older than the Solar System. The discovery of the star was first published in 2000. Observations in 2016 from the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) led to the discovery of two orbiting terrestrial planets, and five more were found in 2017. It takes the seven planets between about 1.5 and 19 days to orbit around the star. They are likely tidally locked to TRAPPIST-1, leading to permanent day on one side and night on the other. Their masses are comparable to that of Earth. Up to four of the planets orbit at distances where temperatures are suitable for the existence of liquid water (diagram pictured), and are thus potentially hospitable to life. This has drawn interest from both researchers and popular culture. (Full article...)

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In the news

José Mujica

Former president of Uruguay José Mujica (pictured) dies at the age of 89.
The Kurdistan Workers' Party announces its dissolution, ending its insurgency against Turkey.
Robert Francis Prevost is elected as Pope Leo XIV, becoming the first Catholic pope born in the United States.
Friedrich Merz is elected Chancellor of Germany and sworn in alongside his coalition government.
Zhao Xintong defeats Mark Williams to win the World Snooker Championship.
In horse racing, Sovereignty, ridden by Junior Alvarado, wins the Kentucky Derby.

Today's featured picture

The short-beaked echidna (Tachyglossus aculeatus) is one of four living species of echidna. It is covered in fur and spines, has a distinctive snout to help detect its surroundings, and uses a specialized tongue to catch insects. Its extremely strong front limbs and claws allow it to burrow quickly. It repels predators by curling into a ball and deters them with its spines. During the Australian winter, it goes into deep torpor and hibernation. As the temperature increases, it emerges to mate. Female echidnas lay one egg a year and the mating period is the only time the solitary animals meet. A newborn echidna grows rapidly on mother's milk and is expelled into the mother's burrow when it grows too large for the pouch. It leaves the burrow when it is around six months old. The species is found throughout Australia and in coastal and highland regions of eastern New Guinea. It is not threatened with extinction, but human activities have reduced its distribution in Australia. This photograph shows a Tasmanian short-beaked echidna (T. a. setosus), a subspecies of the short-beaked echidna, near Scottsdale, Tasmania.

Photograph credit: Charles J. Sharp

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Did you know...

Bertoncelj at the 2015 European Games

... that Sašo Bertoncelj (pictured) competed on MasterChef Slovenia during his gymnastics career?
... that the Knox Mountain Hillclimb is considered very challenging due to every corner being off camber?
... that the works of Yaelokre have been compared to The Lord of the Rings, Gorillaz, and the illustrations of Where the Wild Things Are?
... that Camp Growden was envisioned to become a winter sports complex with toboggan runs?
... that Paddy Higson was known as the "mother of Scottish film"?
... that the robotic costumes used in the Doctor Who episode "The Robot Revolution" were 3D printed in thirty-four different pieces before being assembled?
... that Google searches for the word "fortnight" in the US increased by 868% on the release day of the song "Fortnight" by Taylor Swift?
... that the Green Bay Packers signed Tom Birney as their new kicker in 1979, even though he had not kicked a field goal in more than five years?
... that a 2015 issue of the Strawberry Newspaper features Hello Kitty discussing military conflicts in Afghanistan, Somalia, and Ukraine?

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