January 7 is the seventh day of the year according to the Gregorian calendar. There are 358 days left until the end of the year. In the 20th and 21st centuries, this day corresponds to December 25 of the Julian calendar.

What a holiday on January 7 / photo (Andrii Horb)

On this day, the world celebrates Orthodox Christmas, International Day of Programmers, Day of Untangling Ski Tracks, International Day of Nonsensical Walking, and Day of the Holy Spinner.

In the USA – Ancient Stone Day, Outgassing Day, “I’m a Mentor” Day, Tempura Day, Dumpling Day, “I’m Not Going to Take It Anymore” Day, in Egypt – Goddess Sekhmet Day, in Cambodia – Genocide Victory Day, in Japan – Feast of Seven Herbs “Dzindzitsu”, in Armenia – Memorial Day, Merelots, in Liberia – Pioneers’ Day, in Ghana – Constitution Day, in Italy – Flag Day, Tricolor Day.

Commemorative dates of January 7, anniversaries and events

On January 7, 1610, Galileo Galilei discovered the four largest moons of Jupiter. Now they are called “Galileevs”. Thanks to this discovery, Galileo soon became the most famous scientist in Europe. The book in which he described the discovery was a sensational success, even crowned persons rushed to purchase the telescope. Galileo presented several telescopes to the Venetian Senate, which in gratitude appointed him a professor for life with a salary of 1,000 florins. By the way, the German astronomer Simon Marius (1573-1624) simultaneously and independently of Galileo discovered all four satellites of Jupiter (1610), and named them Io, Europa, Ganymede and Callisto.

History ordered that Galileo is considered the first discoverer of the satellites, after which the names given by Marius were fixed. Jupiter’s moon Ganymede has a larger diameter than Mercury. A global ocean has been discovered under the surface of Europa, and Io is known for having the most powerful volcanoes in the Solar System. Callisto is one of the most cratered bodies in the Solar System. The surface of the satellite is very old, about 4 billion years old, and the geological activity is extremely low. Jupiter has faint planetary rings. Satellites are bright and rotate in orbits far enough from the planet, so they are easy to distinguish even with field binoculars.

Jupiter has been studied by eight of NASA’s Automated Interplanetary Stations. The most important were the studies with the help of the Pioneer and Voyager, later Galileo. The last probe to visit Jupiter was the New Horizons probe on its way to Pluto. To date, scientists know 79 satellites of Jupiter, among which the Galileans are the largest.

In 1785, the Frenchman Jean-Pierre Francois Blanchard, together with the American John Jeffreys, first crossed the English Channel in a hot air balloon.

Since 1935, according to the decision of the IX International Congress of Scientific and Applied Photography, January 7 has been considered the day of the invention of photography. On this day in 1839, a meeting of two French academies took place – the Academy of Sciences and the Academy of Fine Arts. On it, the physicist Dominique Francois Arago made a detailed and brilliant report about the results of many years of research by the French chemist and inventor Louis Daguerre – the method of obtaining an image print (daguerreotype).

It consisted in projecting an image onto a silver-plated copper plate with a camera obscura. The plate pre-cured in iodine vapor should be treated with mercury vapor in the next step. After that, a photo of the projected object was displayed. The first camera weighed 50 kilograms, had plates measuring 16.5 x 21.5 centimeters. While giving a lecture, Arago claimed that the camera is easy to use and anyone can take such photos. It just takes a little practice.

The sensational lecture caused a sensation, and the first daguerreotype camera was sold for 25 thousand dollars on the same day. Plates for the apparatus cost 5 francs. On August 19, 1839, the daguerreotype method was presented to the general public.

What a church holiday today

January 7 – Christmas among Eastern Christians. It is one of the most important Christian holidays and a public holiday in more than 100 countries of the world. In Orthodoxy, Christmas is celebrated on January 7 (in contrast to Catholics, who celebrate it on December 25), it is one of the twelfth holidays and precedes the Christmas fast.

Christmas is the second largest holiday after Easter. It is believed that the way you spend Christmas will be the whole next year. During the Christmas holidays, they greet each other with the words “Christ is born!” and answer “Praise Him!”. On the holiday, it is customary to visit relatives and friends and welcome them to your home, treating them with various delicacies.

What can’t be done today

You can’t engage in hard physical work, quarrel and speak badly.

Signs for January 7

Folk signs today / photo , Denys Pryadko

Weather signs have existed since ancient times.

• there are many stars in the sky – the year will be rich;
• it is snowing – the year will be successful.

Name day on January 7

Vitaly’s name day.