Mathematics is not only crucial to astronomical calculation, but also plays an amazing role in other aspects.
1766, a German astronomer found an interesting rule while sitting at home. He found that when he simply calculated each item in the sequence 0, 3, 6, 12 ... -(n+4)/ 10, he would get 0.4 and 0.7.
Coincidentally, the arrangement order of this new series actually coincides with the semi-major axis of the orbits of all the planets in the solar system calculated in astronomical units at that time!
For example, mercury is 580 billion kilometers away from the sun, which is about 0.386 astronomical unit; Venus is about 0.72 astronomical unit from the sun/kloc-0.82 million kilometers. Needless to say, the earth, 1 astronomical unit; Mars is 228 million kilometers away from the sun, which is about 1.52 astronomical unit, and it is also relatively close. Jupiter is 5.2 astronomical units from the sun.
He finally came to a conclusion that the orbits of the major planets are calculated in astronomical units, which basically conforms to a series: A = 0.4+(2 n× 3)/ 10. Here, the value of n is-∞, 0, 1, 2. ...
But the problem is embarrassing, because Mars is the fourth planet, no problem, but Jupiter has to take the sixth number to meet the data. So, how did n take the fifth number disappear?
It was not until 178 1 that the British astronomer Herschel discovered Uranus, which still conforms to the arrangement of this series.
Scientists speculate that there is an unknown celestial body at the position where n takes the fifth number 3 in the series, that is, A=2.8.
So, astronomers all over the world aim their telescopes at a distance of 2.8 astronomical units from the sun, trying to find potential celestial bodies.
You can't find a place to get it, and it doesn't take much effort to get it. The trace of this mysterious celestial body was actually caught by an Italian priest.
180 1 year, Father Piaz accidentally discovered a tiny celestial body in the telescope. The position of this celestial body is just about 2.8 astronomical units away from the sun, and the motion range is relatively large. It is certain that this is probably the legendary planet.
However, at this time, Piazi fell ill and did not continue to observe. When he woke up, the stars didn't know where to go.
Just when he was at a loss, the math prince Gauss stood up. Gauss believes that astronomy and mathematics are inseparable, and Kepler's planetary laws and Newton's gravity are based on mathematics. Gauss picked up a pen and used his wisdom to create a brand-new theory for calculating planetary orbits. Then, using this theory, Gauss predicted when and where the planet would appear.
180 1, 65438+3 1 In February, the German astronomer Oboth discovered the planet at the position predicted by Gauss, which filled the gap in the Titius sequence. This is the famous ceres.
But after observing Ceres, astronomers found that this planet is really too small, with a diameter of less than 1000 km. Don't compare with the planets in the solar system, even the moon is several times bigger than it. Scientists expressed regret that Ceres was just an accident and did not qualify as a big planet, so the concept of an asteroid was established.
45 years later, astronomers discovered Neptune again. However, Neptune's orbit no longer conforms to Titius's sequence. It can also be known that this series may be just a coincidence, and it is only for fun to find planets, and there is not much scientific basis.
In 2006, Ceres was classified as a dwarf planet by astronomers after becoming the main asteroid for nearly 200 years, and became a member of Pluto.
So, since Ceres is not a planet that should be in the Titius series, does this mean that there are no planets here? What's the secret of the huge gap between Mars and Jupiter? I'll introduce it in the next issue ~