Solar apex

The Sonnenapex (Latin: apex = peak, crest, helmet ) is the vanishing point of the movement of our sun compared to the average of the neighboring bright stars and is located in the constellation Hercules, southwest of Vega. The opposite direction is called Antapex and is located in the constellation pigeon.

The first determination of the apex was carried out in 1783 by William Herschel. From 1822 also Carl Friedrich Gauss calculated with very different methods to Sonnenapex that bills itself but never released. Later, the main method of Auguste Bravais and George Biddell Airy was independently rediscovered. Only after 1900 that it became clear that a major difficulty rests in the determination of the apex of the solar motion on the anisotropic velocity distribution of the stars. After the current values ​​from the beginning of the 21st century, the Sun moves at 19.7 km / s toward the apex, which lies at a galactic longitude of 57 ° and a galactic latitude of 22 °.

The Apexbewegung must be considered in the evaluation of velocity measurements in the Milky Way in order to benefit from the speed relative to the sun conclusions as to the actual galactic movements.

Following the Sonnenapex earthmoving is called relative to the Sun as Erdapex especially in meteor observations of the vanishing point. The Erdapex wanders behind on the ecliptic by approximately 90 degrees in the course of a year the sun. So he is in the early morning hours especially high in the sky, which is why you can often count more meteors in the second half of the night than in the first half of the night. From Earth, seen then you look in the direction in which the earth moves at about 30 km / s. The dust particles, while they " collect " as meteors ( shooting stars ), one can then see very well.