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Habitable zones ofTRAPPIST-1 and the Solar System

TRAPPIST-1 is a coolred dwarf star with seven knownexoplanets. It lies in the constellationAquarius about 40.66light-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 theSolar System. The discovery of the star was first published in 2000. Observations in 2016 from theTransiting Planets and Planetesimals Small Telescope (TRAPPIST) led to the discovery of two orbitingterrestrial 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 likelytidally locked toTRAPPIST-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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Bertoncelj at the2015 European Games

... thatSašo Bertoncelj(pictured) competed onMasterChef Slovenia during his gymnastics career?
... that theKnox Mountain Hillclimb is considered very challenging due to every corner beingoff camber?
... that the works ofYaelokre have been compared toThe Lord of the Rings,Gorillaz, and the illustrations ofWhere the Wild Things Are?
... thatCamp Growden was envisioned to become a winter sports complex with toboggan runs?
... thatPaddy Higson was known as the "mother of Scottish film"?
... that the robotic costumes used in theDoctor Who episode "The Robot Revolution" were3D 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" byTaylor Swift?
... that theGreen Bay Packers signedTom Birney as their newkicker in 1979, even though he had not kicked afield goal in more than five years?
... that a 2015 issue of theStrawberry Newspaper featuresHello Kitty discussing military conflicts in Afghanistan, Somalia, and Ukraine?

In the news

José Mujica

Formerpresident of UruguayJosé Mujica(pictured) dies at theage of 89.
TheKurdistan Workers' Party announces its dissolution, endingits insurgency against Turkey.
Robert Francis Prevostis elected asPope Leo XIV, becoming the first Catholicpope born in the United States.
Friedrich Merz is electedChancellor of Germany and sworn in alongsidehis coalition government.
Zhao Xintong defeatsMark Williams to winthe World Snooker Championship.
In horse racing,Sovereignty, ridden byJunior Alvarado, winsthe Kentucky Derby.

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On this day

May 17:International Day Against Homophobia, Biphobia and Transphobia

Anne of Denmark

1590 –Anne of Denmark(pictured) was crowned thequeen consort of Scotland ina ceremony atHolyrood Abbey in Edinburgh.
1863 –American Civil War: At theBattle of Big Black River Bridge in Mississippi,Union forces underJohn A. McClernand defeated aConfederate rearguard and captured around 1,700 men.
1900 – The first copies of the children's novelThe Wonderful Wizard of Oz byL. Frank Baum were printed.
1954 – TheU.S. Supreme Court ruled in the landmark caseBrown v. Board of Education, outlawingracial segregation inpublic schools because "separate educational facilities are inherently unequal" and therefore unconstitutional.
1987 – An Iraqi jetfired two Exocet missiles at the American frigateUSS Stark, killing 37 personnel and injuring 21 others.

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Theshort-beaked echidna (Tachyglossus aculeatus) is one of four living species ofechidna. It is covered in fur andspines, has a distinctivesnout to help detect its surroundings, and uses a specializedtongue to catch insects. Its extremely strong front limbs and claws allow it to burrow quickly. It repelspredators bycurling into a ball and deters them with its spines. During the Australian winter, it goes into deeptorpor andhibernation. As the temperature increases, it emerges tomate. Female echidnas lay one egg a year and the mating period is the only time thesolitary 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 easternNew Guinea. It is not threatened with extinction, but human activities have reduced its distribution in Australia. This photograph shows aTasmanian short-beaked echidna (T. a. setosus), a subspecies of the short-beaked echidna, nearScottsdale, Tasmania.

Photograph credit:Charles J. Sharp

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