Sirius, also known as α α Canis Majoris, is the brightest star of the day except the Sun, but is fainter than Venus and Jupiter, and brighter than Mars most of the time. Sirius generally refers to Sirius A, and its main system consists of a blue-white blue dwarf and a blue white dwarf, with a center of mass about 8.6 ly from Earth.

Chinese Sirius Foreign name Sirius Alias α Canis Majoris / α CMa Classification A: Blue Dwarf B: White Dwarf Mass A: 2.063 ± 0.023 M⊙ B: 1.018 ± 0.011 M⊙ Average density B: 10^7 kg/m³ Diameter A: 1.711 D⊙ B: 0.0084 ± 0.03 D⊙ Surface temperature A: 9940 K B: 25000 ± 200 K Apparent magnitude A: -1.47 B: +8.44 System:-1.46 Absolute Magnitude A:+1.42 B:+11.18 Right Econtomy System:06h 45m 08.91728s Declination System:-16° 42′ 58.0171" Distance from ground System:8.60 ± 0.04 ly (2.64 ± 0.01 pc) Semi-major axis 7.4957 ± 0.0025" Eccentricity 0.59142 ± 0.00037 Revolution period 50.1284 ± 0.0043 yr Flat periapsis angle149.161 ± 0.075° Orbital inclination136.336 ± 0.040° Ascending node longitude45.40 ± 0.071° Spectral type A: A0mA1Va B: DA2 U-B Color index A: -0.05 B: -1.04 B-V Color index A: +0.00 B: -1.03 Light A: 25.4 L☉ B: 0.56 L☉ Table of Contents1 Discovery history

2 Astronomical data

3 Find a way

4 Documenting applications

5 Methods of observation

6 Sirius A

7 Sirius B

8 Sirius Clusters

9 Zodiac Culture

▪ Origin of the name

▪ Poetry Records

▪ Ancient Egyptian culture

▪ Roman culture

▪ Asian culture

▪ Culture of the Americas

10 Related Accounts

11 Tribal Mysteries

History of Sirius' DiscoveryEdit In 1844, the German astronomer Bessel deduced that Sirius was a double star based on the wave pattern of its path, because the star moved in the nearby space along a wave-like trajectory, thus concluding that it had a companion star and an orbital period of about 50 years. The companion star was named in 1862 by the American astronomer A. Clark. Clark was the first to see with his homemade refracting astronomical telescope.

Sirius is the brightest star of the day, with a visual magnitude of -1.46, and in the western constellation, it is a double star in the constellation Canis Major. Of course, the ancients of our country also paid attention to this bright star, and called this most striking star located in the south of the "Que Qiu" and the most striking star in the well as the "Wolf Star". Therefore, for the peace of the territory, the ancients set up a curved bow to shoot the wolf in the southeast of the "Wolf Star" - "arc arrow", the bow and arrow composed of these 9 stars are very vivid, the arrow is on the string, the bow has been rounded, and the arrow points directly to the "Wolf Star" in the northwest direction. Su Shi once wrote a poem to describe it vividly: "Will hold the bow like a full moon, look northwest, and shoot the wolf." However, the main function of this longbow is to deter the "wolf" by force, and the real means of capture is to rely on a wolf trap surrounded by the 13 stars of the "military market" not far to the west. In order to lure the wolf, the hunter also placed a "pheasant" 1 star in the trap as bait. [1]

Sirius Astronomical DataEdit Sirius Position and Volume Both Sirius and its companions orbit each other in orbits with a fairly large eccentricity, with an orbital period of about 50 years and an average distance of about 20 AU. Despite the bright star's radiance, it is not difficult to see the companion star of magnitude 8.44 with a large telescope. The companion star has a mass about the same mass as the Sun, but its radius is only the size of the Earth, and its density is much greater than that of the Sun, with an average density of 10^7 kg/m³, making it the first white dwarf to be discovered.

The bright star in the binary star is a 25.4 L⊙ early type A Am blue dwarf with a volume slightly larger than the Sun, with a radius of 1.711 R⊙ and a surface temperature about twice the Sun's surface temperature, about 9940 K, which is blue-white in color. The coordinates of Sirius' centroid on the celestial sphere are right ascension 06h 45m 08.91728s, declination -16° 42' 58.017" (epoch J2000.0), right ascension centennial self -0'.553, declination centennial self -1'.205 (data taken from FK405 ephemeris table). Sirius A is the first bright star of the day (the smallest apparent magnitude) and belongs to the blue dwarf star of the main sequence. Sirius B, commonly known as Sirius companion, is a white dwarf with a slightly larger mass than the Sun and a smaller radius than Earth, and its material is mainly in a degenerate state. The orbital period of the two satellites is about 50.1284 ± 0.0043 years, the orbital eccentricity is 0.59142 ± 0.00037, and the distance from the Earth is about 8.6 ± 0.04 ly.

Whether Sirius is a close binary star or not is related to the evolution of the Sirius binary. Sirius was recorded in red in ancient times, which provides us with clues to our research. X-rays from Sirius were discovered in 1975, and some believe that this may be the thermal radiation from the depths of the atmosphere of almost pure hydrogen of star B, while others believe that it may be produced by star A or star B's hot corona. According to the data in 1980, the High Energy Observatory 2 satellite measured the X-rays of the 0.15~3.0 keV band of Star A and Star B respectively, and it was known that the X-rays of Star B were much stronger than those of Star A.

How to find SiriusEdit Sirius is only easily visible in winter or early spring. There are several ways to find Sirius:

1. Samsung

Orion is very easy to find, and the three stars in a tight line between the two bright stars should also be visible. Looking southeast along the three stars, a very conspicuous star is Sirius.

Patrolling southeast along the three stars of the Hunter's Belt, you can see an exceptionally bright star with a blue-white glow, which is the brightest star in the night sky: Sirius, with an apparent magnitude of -1.46. Sirius, or Alpha Canis Major, forms the outline of a dog with some of the other brighter stars in Canis Major, and Sirius is on the canine's mouth.

2. Winter Triangle

This method is not so intuitive, there is a brighter Nanhe 3 due east of Betelgeuse on the left side of Orion, and the line between Nanhe 3 and Betelgeuse is vertically bisected to the south, and he will be found. Betelgeuse, Sirius, and South River make up the famous "Winter Triangle".

The above two methods are commonly used, in fact, the easiest way to find Sirius is to look at the southern sky at about 22 o'clock in the evening around the Spring Festival, the brightest one, the altitude angle is about 40 degrees, which star is the brightest, is Sirius, of course, the premise is to exclude the planets. Planets generally orbit the same as the Moon in the night sky, with Sirius lower.

In China, Sirius' orbit is always in the southern part of the sky. The further north it goes, the lower the altitude angle of Sirius.

Sirius Chronicle ApplicationEdit Sirius has appeared in the earliest astronomical records and was considered by the ancient Egyptians as "Sopradet" (Greek: Seirios) [Egyptian]: Sothis. During the Middle Kingdom, the Egyptian calendar began on the day Sirius rose with the sun, and that morning, Sirius, far enough from the Sun, was able to rise earlier than the Sun, avoiding the glare and reappearing in the sky after 70 days of disappearance. The importance of this day in the calendar is due to the fact that it is also shortly before the Nile cycle flooding and the summer solstice. The hieroglyphs of "Sopradit" are a star and a triangle. The 70 days that Sirius disappeared from the sky symbolized in mythology the days when Thorpudette and Isis spent the Egyptian underworld.

The ancient Greeks believed that the appearance of Sirius represented a hot and dry summer with the withering of plants, weakness of men, and irritability of women. Because Sirius is so bright, it will twinkle more violently in the unstable weather of early summer, indicating that something bad is coming. People affected by its effects are known as suffering from "astroboletos" (αστροβολητο?) or "Star-Struck". In the written record it is written as "burning" or "flame". The season following the appearance of this star is known as the "dog day" of summer. The natives of the Aegean island would sacrifice Sirius and Zeus for a cool breeze, and would wait for Sirius to appear the following summer. If it rises brightly, it is a good sign of prosperity, but if it rises in a cloudy or dim manner, it is a sign of a plague. 3rd-century BC coins excavated from the island are engraved with glowing dogs or stars, demonstrating Sirius' importance. The Romans celebrated the sunset of Sirius around April 25 by offering a dog, incense, wine and a sheep to Robigo, the Roman god of the withered grains, in the hope of stopping the rust brought by the starlight that year.