Ceres' information

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ceres

Ceres (1 ceres) is the first asteroid discovered by human beings. It was discovered by Piaz, an Italian, on 180 1 year 1 month 1 day. With an average diameter of 952 kilometers, it is the largest and heaviest celestial body in the asteroid belt.

(discovery):

In 1766, a German middle school math teacher named Titius put the following series:

Add 0 ... before 3,6,12,24,48,96, 192, that is:

0, 3, 6,12, 24, 48, 96,192 ... and then add 4 to each number to get the following series:

4,7, 10,16,28,52,100,196 ... then divide each number by10, and finally get:

0.4,0.7, 1, 1.6,2.8,5.2, 10, 19.6……

To Titius's surprise, he found that each item in this series is related to the ratio of the distances between the six known planets (namely, Mercury, Venus, Earth, Mars, Jupiter and Saturn) and the sun (the distance between the earth and the sun is set to 1 unit).

Titius's friend and astronomer Bode knew the significance of this discovery and announced Titius's discovery in 1772. This string of numbers has attracted great attention of scientists since then. And known as the Titius-Bode law, namely:

Uranus, Neptune and Pluto had not been discovered at that time, and Saturn was considered as the farthest planet from the sun.

178 1 year, the British German Herschel discovered Uranus near 19.6 (that is, the eighth item in the series). Since then, people have been convinced of this. According to this rule, there should also be a planet at the position of 2.8, which is the fifth item in the series, but it has not been discovered yet. As a result, many astronomers and astronomy enthusiasts embarked on a journey to find this new planet with great enthusiasm.

On New Year's Eve of 180 1, Italian astronomer Piazi was still observing the starry sky with rapt attention. Suddenly, he found a very small star from the telescope, just at the position of 2.8 in Titius-Bode Law. However, when Piazi wanted to observe the asteroid further, he fell ill. When he recovered and tried to find the asteroid again, it disappeared. Piazi didn't give up this accidental opportunity. He thought it might be a planet that people had never discovered before, and named it Ceres.

Astronomers hold different views on Piazi's discovery. Some people think that Piazi is right; Some people think it may be a comet, otherwise why did it just show one side and disappear?

Months have passed, and people's statements are still unclear. However, this debate has attracted the attention of German mathematician Gauss. Gauss thought, since astronomers can't find Ceres through observation, can they find it through mathematical methods? Many astronomers disagree with Gauss's idea. Astronomers can't find Ceres. Can Gauss work it out? Friends also advised him not to waste time and intelligence on this hopeless problem.

Young gauss has his own opinion. He thinks astronomy and mathematics are inseparable. Without a strong knowledge of mathematics, it is impossible to be an excellent astronomer. The same is true in the history of astronomy. It was with his mathematical talent that Kepler discovered the three laws of planetary motion. Newton also discovered the law of gravity with his profound mathematical knowledge.

Before Gauss, the famous mathematician Euler had developed a method to calculate the orbits of planets. But this method is too troublesome. Gauss is determined to find a simple method. On the basis of predecessors, Gauss created a brand-new theory of planetary orbit calculation with his outstanding mathematical ability after hard operation. According to Piaz's observation data, he used this method to calculate the orbital shape of Ceres in only one hour, and pointed out when it would appear in which sky.

On the nights of 180 1, 65438+2, 3 1, German astronomer Olbers aimed his telescope at the sky within the time predicted by Gauss. As expected, Ceres appeared!

Gauss's calculation method succeeded. After hiding for a whole year, the planet that Gauss found from the pen tip became the best New Year gift for mankind. This gift shows people the great role of mathematics in scientific research.

Before discovering asteroids, Piazi looked for Meyer 87 in Francis wollaston's catalog, but he couldn't find the position described in the catalog. Then he found a moving star. At first he thought it was a comet.

Piaz continued to observe February 1 1, but his findings were ignored. Since then, the asteroid has been in orbit to the back of the sun and cannot be observed. Later, German mathematician Gauss estimated its orbit according to three observations of Piazi, and this celestial body was successfully recovered by Franz Seville, Baron von Zack and Olbers the following year. Another astronomer, Bode, thinks that there should be a planet between the orbits of Mars and Jupiter. Ceres is what he thinks is an unknown planet, but its volume is much smaller than other big planets, so William Herschel later called this celestial body an "asteroid".

Features:

Ceres is by far the largest celestial body in the asteroid belt, but with the discovery of Kepler belt and its celestial bodies, celestial bodies larger than Ceres have been discovered one after another, including (28978) asteroid (Ixion), (50000) quaoar, (90482) asteroid (Orcus) and the recently discovered 2003UB365433. Pluto is sometimes considered as a celestial body in the Kepler belt.

At the end of 2003 and the beginning of 2004, the Hubble Space Telescope photographed Ceres for the first time and found that it was quite spherical with different albedo on its surface. People think it has complex terrain, and some astronomers even speculate that Ceres has an icy mantle and a metal core.

In June 2006, NASA will launch the Dawn probe to Ceres, which is expected to arrive in August 20 15.

physical data

The diameter is 959.2×932.6 km.

The mass is 9.445× 1020kg.

Density: 2.05g/cm3

Surface gravity 0.26 m/s?

The escape speed is 0.51km/s.

The rotation period is 0.378 1 day.

Spectral classification of G-type asteroids

Absolute magnitude 3.34

The albedo is 0. 1 13

Average surface temperature ~ 230 k

The largest known asteroid in the solar system, the first asteroid discovered by G Piazi of Palermo Observatory, was discovered on New Year's Day of 180 1. Then the observation was interrupted until the last day of 180 1, and it was found again by Gaussian orbit calculation. Ceres orbits the sun only once every 4.6 earth years, with a diameter of about 1000 km. According to the latest issue of Nature magazine, Ceres has long been considered as one of tens of thousands of asteroids in the asteroid belt between Mars and Jupiter. But scientists have recently discovered that Ceres may contain more fresh water than the earth. This asteroid is also very similar to the earth in other ways. Astronomers used the Hubble Space Telescope to take 267 photos of Ceres. By Cornell University scholar Peter? The team led by Thomas found that Ceres was almost spherical. This shows that its shape is controlled by gravity. In addition, the material of this asteroid is not evenly distributed inside. The computer model shows that Ceres is divided into different layers: dense matter is in the core and lighter matter is near the surface. It may include a surface rich in ice water and a rock core. According to the report published by the American Institute of Space Telescope Science, if the surface of Ceres is composed of 25% water, then its fresh water content is more than that of the earth.

English name: Ceres

? Chinese name: Sellesi.

? Symbol: harvest

? Season: autumn

? Psychological aspects: pregnancy, food, family, motherland, work and child-rearing are regarded as symbols of mothers.

? Astrological significance: used to judge the characteristics of maternal tendency.

?

? In Greek mythology, the goddess of harvest is Demeter. In Roman mythology, Ceres is the goddess in charge of agriculture and harvest, symbolizing the fertile ground for human civilization. She is worshipped as a mother who nourishes all beings. There is such a story in mythology:

? Thrace's daughter Persephone was suddenly kidnapped by Pluto, the ghost god. Hearing the bad news, Israel was very sad. He didn't care about his work, so thousands of plants in the world slowly withered. It was not until her daughter came back that she recovered. So in an instant, the seeds of the world began to sprout, the flowers began to bloom, and the farmland was covered with green crops.

? The goddess of Israel is the mythical god of agriculture. She nurtures everything and is regarded as a symbol of her mother. Besides the moon, it is the second index about mother. Represents pregnancy, food, family, motherland, labor and work and parenting.

? Ceres is the first asteroid discovered by humans in the asteroid belt between Mars and Jupiter. This asteroid named Ceres was discovered by Italian astronomer Piazi in 180 1 year. Its diameter is about 933 kilometers, which is equal to 1/4 of the moon's diameter, and its mass is about 1/50 of the moon, also known as 65438. When it was first discovered, it was listed as one of the eight planets.

? According to statistics, about 500,000 asteroids in the solar system revolve around the sun like nine planets, and there are more than 8,000 registered asteroids. Most of them are small. Among the first four asteroids (Ceres, Pallas Athena, Juno and Vesta), Ceres is the largest one and is often called "the great mother". This title comes from those distant Roman myths.

? Ceres will hit the sun every May around 1 1. At that time, Ceres, the earth and the sun will be in a straight line, the earth will be between them, and the brightness of Ceres will reach the highest value. In the next ten days, astronomy enthusiasts can see their beautiful images through binoculars.

? According to the latest issue of Nature magazine, Ceres has long been considered as one of tens of thousands of asteroids in the asteroid belt between Mars and Jupiter. But scientists have recently discovered that Ceres may contain more fresh water than the earth. This asteroid is also very similar to the earth in other ways. Astronomers used the Hubble Space Telescope to take 267 photos of Ceres. By Cornell University scholar Peter? The team led by Thomas found that Ceres was almost spherical. This shows that its shape is controlled by gravity. In addition, the material of this asteroid is not evenly distributed inside. The computer model shows that Ceres is divided into different layers: dense matter is in the core and lighter matter is near the surface. It may include a surface rich in ice water and a rock core. According to the report published by the American Institute of Space Telescope Science, if the surface of Ceres is composed of 25% water, then its fresh water content is more than that of the earth.

? Interestingly, many international environmental protection websites use Ceres logo to express their determination to protect the environment. This may not be just a coincidence.