What is Sirius?

Sirius, also known as Canis Majoris, is the brightest star in the world except the sun, but darker than Venus and Jupiter, most of the time brighter than Mars. Sirius generally refers to Sirius A. Its main system consists of a blue-white blue dwarf and a blue white dwarf. The center of mass is about 8.6 ly from the earth.

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Sirius is easy to see only in winter or early spring. There are several ways to find Sirius:

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   Sirius' apparent magnitude is about -1.46, making it the brightest star in the night sky, almost the second brightest.

   Sirius A is a blue dwarf with a radius of about 1.711 R. The optical interferometer measures the star's radius, and the estimated angular diameter is 5.936 ± 0.016 mas. Its rotation speed is about 16 km / s, so it does not effectively squash the star into an oval shape. The weaver star rotates at a higher speed of 274 km / s, making it a flat sphere.

   Celestial model states that Sirius A formed once

   Sirius B has a mass greater than that of the Sun and is one of the white dwarfs known to have the highest mass. It has almost 1.1 M. Yet so much matter has been compressed to about the size of the Earth. Its surface temperature is 25000 ± 200 K. However, since there is no energy generated inside, the remaining heat will be radiated into outer space, and Sirius B will eventually cool down, which will take more than 2 × 10 ^ 8 years.

   A star does not become a white dwarf until it passes through the main sequence and red giant phases. About 1.2 × 10 ^ 8 years ago, Sirius B may be a more luminous blue dwarf, with a spectrum between B4-B5 and a mass of about 5M. When Sirius B became a red giant, it could increase the amount of metal in its companion Sirius A.

   Sirius B was originally composed of carbon and oxygen. These two elements were produced by the fusion of helium in the dead star of Sirius B. These elements are covered by lighter elements and are layered according to mass, because Sirius B has a high surface gravity. Therefore, the outer atmosphere of Sirius B is almost pure hydrogen, the lightest element in the universe,

   In 1909 Echner Hertzpron was the first to propose Sirius as one of the Ursa Major moving constellations, and he came to this conclusion after observing the Sirius system's movement path in the sky.

   The Ursa Major cluster is composed of 220 stars and has the same path in space. When it first formed, it was part of an open cluster, and it has gradually moved away from gravity. However, analyses made in 2003 and 2005 suggest that Sirius may not belong to this cluster. The Ursa Major cluster is estimated to be 4 × 10 ^ 8 to 6 × 10 ^ 8 years, and Sirius has a metal content similar to that of the sun, so the age may be only 2 × 10 ^ 8 years, which is too young for this cluster.

   Sirius may belong to a proposed "Sirius Star Cluster". In addition, the evacuated stars that may belong to this cluster include in Auriga, in North Corona, in Jupiter, in Pojiang, and in Serpent. This cluster is one of three clusters within 500 light years of the Sun. The remaining two are

   Sirius and Arc Vector. All in the wells. Sirius is the brightest star of the day. Nine stars of arc vector, located southeast of Sirius, eight stars are like bow arcs, and one star is like vector, so it is called arc vector.

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   Astronomy in Dogan Mythology

   The Dagongans, who live in the southern mountains of the Timbuktu region of the Republic of Mali, are one of the indigenous peoples in Africa who still maintain primitive jungle life.

   In 1930, two French ethnographers Marcel Gliogli and Joma De Dilon penetrated into the primitive tribes of Dogan, collecting many unique myths and legends. They accidentally discovered that the mystery of Sirius' discoloration that had been debated by astronomers for a century, and found the answer in the myths and legends of the Dogan people.

   Sirius is one of the brightest stars visible to the naked eye in the night sky, although it is 8.6 ly away from Earth. Many ancient astronomical works record that Sirius is dark red, but Sirius in the eyes of modern people is white. Why has the color of Sirius changed? This mystery is deeply attracting scientists.

   The Dogonians told French scientists that Sirius is composed of a large star and a small star. The small star is a black, dense and invisible companion star, which moves around the large star in an elliptical orbit. They also know that the small star's motion cycle is 50 years. They have been passed down from generation to generation. Sirius is the smallest and heaviest star in the sky. There is a luminous metal substance not found on Earth. In an accident, the Sirius companion suddenly exploded and occurred The intense light gradually dimmed. Although the dang companion was not visible to the naked eye, the old people were able to draw the running course and various figures of the two stars on the ground with a cane. When Sirius appeared between the two peaks, a sacrifice called Xigui was held every 60 years. It was the most solemn religious event.

   Dumbledore believes that the Dogon's knowledge of Sirius is both detailed and accurate. As we can see, they are just like us. They associate Tianruixing with an invisible companion. The Tagan people called this companion a "Certex". The Takaoka called it the Valley Star, probably because it was so small that it was almost invisible. According to the Takaokas, "Certex" is made of the heaviest metal known, which is even heavier than iron. This means that Takaoka people know that Celestial Star B has a great density.

   The Dogon people also painted many sacrificial drawings about Sirius system. These paintings show that the Dogon people understand that Sirius B's orbit around Sirius A is elliptical, and Sirius A is at the center. According to Dagaan legends, Dumbler even drew a picture of Sirius and "Cerus" swinging orbits, and found that it is amazingly the same picture drawn by modern astronomers Sirius A and B similar.

   According to the Dogan people, their ancestors' knowledge of Sirius B was imparted by a god named "Silent". So far, the Dogan people still keep a picture clearly showing that the "god" they believe in descends from the sky in a large spaceship dragged by flames and falls to their clan.

   The Dogan astronomical tradition is not limited to Sirius. They say that Jupiter has four moons and Saturn has a halo, and they represent these two planets in the picture they draw.

   A Possible Interpretation of the Asoka Knowledge

   Karl Sagan, a famous American astronomer and popular science writer, wrote a possibility analysis of the source of Astronomical knowledge of the Dogan people in the article "White Dwarfs and Little Green Man", thinking that they may be more advanced in science and culture in recent times. Europeans had contact, perhaps from Europeans' visits to Africa, perhaps from a school somewhere in France, or from West Africans who had contacted Europeans in the First World War to fight for the French.

   The main arguments are as follows:

   First, a Cornell University research team discovered a ring around Uranus in 1977-a discovery that has never been implied in ground observation. Advanced alien civilization can observe our solar system near the earth, and it should be possible to discover these rings of Uranus without difficulty. But European astronomers in the nineteenth and early twentieth centuries never mentioned it. The fact that the Dogons don't talk about a planet other than Saturn with rings suggests that the myths provided by the Dogons may come from Europeans.

   2. The fact that Sirius has a companion star was discovered by the German astronomer F.W. Bessel in 1844, and the joint rotation period was calculated to be 50 years. Eighteen years later, Alvan G. Clark directly observed the companion star with an 18½-in refracting telescope. At the beginning of the 20th century, the European astronomy community has determined that the companion star is an unusually dense white dwarf, weighing about 1 t / in³. All this happened just before Griole came into contact with the Dogon legend about Sirius.

   3. Diplomats, explorers, adventurers, or early anthropologists from Francefor example, Richard Francis Burtonwas in West Africa in the first few decades of the 20th century May have exchanged some knowledge of the brightest Sirius in the sky with the indigenous people of Dogan. This knowledge was disseminated, retelled by locals, and finally incorporated into the Takan myth.

   Carl Sagan also interviewed Native Americans in the southwestern United States and Native Guinea's indigenous explanations of the cause of the disease as an anthropologist in two similar cases, illustrating the possibility of this phenomenon. ^[1]