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Habitable zones of TRAPPIST-1 and the Solar System
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 the 2015 European Games
Bertoncelj at the2015 European Games

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May 17:International Day Against Homophobia, Biphobia and Transphobia

Anne of Denmark
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Short-beaked echidna

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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