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The Sun

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The sun is an ordinary  star , one of about 100 billion in our   galaxy , the Milky Way. The sun has extremely important influences on our planet: It drives weather, ocean currents, seasons, and  climate , and makes plant life possible through  photosynthesis . Without the sun’s heat and light, life on Earth would not exist. The Sun moves around the Galactic Center  of the Milky Way , at a distance of 26,660 light years . From Earth, it is  about 8 light minutes  away. It’s diameter  is about 109 times that of Earth . It’s mass  is about 330,000 times that of Earth, making up about 99.86% of the total mass of the Solar System.  Roughly three-quarters of the Sun's mass  consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen , carbon , neon , and iron . The sun was born about 4.6 billion years ago. Many scientists think the sun and the rest of the solar system ...

TON 618

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Tonantzintla 618  is a supermassive black hole located in the constellation of Canes Venatici and Coma Berenices. It’s around 18.2 billion light years from Earth and mass of 66 billion solar masses.  TON 618 has a radius of over 1,000 astronomical units (AU), which means that if the black hole was placed in the center of the solar system , by the time you reached Pluto, you would be less than 5% of the way from the center of the black hole to its edge.  TON 618 powers a quasar, one of the brightest objects in the entire universe with the illuminating power of 140 trillion suns. Quasars draw light from the gravitational energy of the central hole.   Due to the brilliance of the central quasar, the surrounding galaxy is outshone by it and hence is not visible from Earth. Astronomers first spotted it in a 1957 survey from the Tonantzintla Observatory in Mexico but didn’t realize what it was. They first thought it was a faint blue star, but observations a decade later re...

Kepler-22

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Kepler-22  is a star , located in the northern constellation of Cygnus. The star is orbited by a planet that is located within the star's habitable zone . The estimated distance of Kepler-22 is approximately 620 light-years away from our solar system. Kepler-22 is slightly smaller and cooler then the Sun.  On December 5th, 2011 , scientists from the Kepler mission announced that a possible Earthlike planet - Kelper-22b . It’s  super-Earth (size of 9 Earths) that could be covered in super ocean. The habitable zone is the region in which liquid water could exist on a planet's surface. Liquid water is a key ingredient to life, so planets found within this zone are more likely to be habitable worlds. However, planets must also be the right size, and Kepler-22b is too big.  Planet’s orbital period is around 300 days which is similar to our environment.  Kepler-22b's first transit  in front of its host sun was observed  on Kepler's third day of scientif...

TRAPPIST-1

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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 .  The system is far too faint to be seen with the unaided eye.  Around a star which is 12 times less massive than the Sun and only slightly larger than Jupiter, there are at least seven planets in orbit. They  have sizes and masses comparable to the Earth and Venus.  Because we know the distance of the planets to their star, and the temperature of the star, we can deduce that they receive an amount of light that is similar to many of the planets in the Solar system, from Mercury to Mars.  Three or four of them reside within their star's habitable zone, meaning they orbit at the right distance to support liquid water on their surfaces .   TRAPPIST stands for "Transiting Planets and Planetesimals Small Telescope," which is actually a pair of telescopes: one at the European Sout...

Neptune ❄️

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Neptune , Eighth planet  from the Sun and t hird most massive  of the solar system , discovered in 1846 and named for the Roman god of the sea, w ho is identified with the Greek deity Poseidon , a son of the Titan  (the Roman god Saturn ) and a brother of Zeus  (the Roman god Jupiter ).  Because of its great distance from Earth , it cannot be seen with the unaided eye.  Neptune is almost four times the size of Earth but slightly smaller than Uranus , which makes it the smallest in diameter of the four giant.  In 2011 planet completed its first orbit since its discovery in 1846.  One day  takes about 16 hours (the time it takes for Neptune to rotate or spin once). And makes a complete orbit around the Sun (a year in Neptunian time) in about 165 Earth years (60,190 Earth days).  Planet  has 14 known moons. It's largest moon Triton was discovered on October 10, 1846, by William Lassell, just 17 days after Johann Gottfried Galle discove...

Cat’s eye nebula 🌌

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The Cat’s Eye Nebula, also known as NGC 6543, is a planetary nebula located 3,000 lightyears away in the constellation Draco.  Planetary nebulae are one of the final stages of a Sun-like star, as they run out of fuel and begin losing their outer layers into space.   The Sun will end its life in similar fashion in about five billion years. It will first expand into a red giant with a diameter about 100 times greater than it originally was. At the centre of the Cat's Eye Nebula is a dying Wolf Rayet star.  The star is believed to have originally had a mass of around 5 times that of the Sun and is now estimated to have only over one solar mass.  Wolf-Rayet stars are hot (25-50,000+ degrees K), massive stars (20+ solar mass) with a high rate of mass loss. Th e type was first distinguished in 1867 by the French astronomers  Charles-Joseph-Γ‰tienne Wolf and   Georges-Antoine-Pons Rayet. Credits:  https://m.youtube.com/watch?v=Gis6G2hVNaE https://hubblesite.or...

North Star 🌟

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Polaris , also called   Alpha Ursae Minoris , Earth ’s present northern polestar, or North Star, at the end of the “handle” of the so-called Little Dipper  in the constellation Ursa Minor .  It’s classed as supergiant star, which can be red or blue (North Star is light blue).  Pole Star  is a visual double star which can be observed only with the help of very large telescopes.  Thanks to its high brightness, Polaris is clearly visible when observed from locations with dark skyes, and should be also quite easily visible from light polluted areas.  Pole Star is famous for holding nearly still in our sky while the entire northern sky moves around it. That’s because it’s located very close to the north celestial pole , the point around which the entire northern sky turns.  Althoug  it’s a common belief, Polaris is  not  the brightest star in the nighttime sky. In fact, it’s only the 48th brightest star .  North Star  is distan...