According to astrocalendars, compiled by amateurs of astronomy, this year is rich in interesting events - conjunctions and oppositions of planets, rare eclipses, a round dance of Jupiter's satellites, bright asteroids and meteor showers. One of the nearest dates is associated with Mercury - January 30.
Remarkable eclipses
When the Sun falls into the shadow of the Moon, they speak of a solar eclipse. And when the Moon hides in the shadow of the Earth - about the moon. There are a maximum of seven eclipses per year. But now is not the case: earthlings will see two lunar and two solar.
The first is on May 26, 2021: on this day, the Moon will be in the cone of the earth's shadow. In part, residents of the eastern regions of Russia will be able to trace it, and only our Australian antipodes will be able to trace it entirely.
The next lunar eclipse will occur on November 19. The residents of Chukotka and Kamchatka will see it in full. They will also be lucky to observe the annular eclipse of the Sun on June 10. Usually the lunar disk overlaps the star, but this time our satellite will be slightly farther, the apparent diameter of the disk will become smaller than the solar one, and light will peep out from under its edges - in the form of a ring. Hence the name of the phenomenon.
According to Roscosmos, an annular solar eclipse will be seen on the territory of Russia for the first time in 50 years. It will last almost four minutes. It will be partially observed everywhere, except for the very south of the country. And on May 26, the supermoon will come - the moment of the closest approach of the Moon to the Earth. The disk of our natural satellite will become especially large and bright.
The last eclipse of the year - total solar - will take place on December 4 and will take place in the Pacific and Atlantic oceans, Antarctica. In Russia, he will not be seen even partially, as noted in the astro-calendar compiled by the amateur astronomer Alexander Kozlovsky.
Merry companions
One of the most interesting astronomical phenomena available to amateurs and beginners to observe is the covering, when one celestial body obstructs another. In this sense, an eclipse is also a covering. By following them, you get a considerable chance to contribute to science. For example, in 1977, in this way they learned about the existence of rings in Uranus.
There will be seven lunar coverings this year. The visible disk of the Moon will hit Mercury and Venus twice and Mars three times.
Astronomer Sergei Guryanov draws attention to the coverage of stars by asteroids. The most interesting - on November 2: the star beta Aries will be blocked by the asteroid of the main belt (552) Siegelinda. The event can be filmed throughout Russia. If you're lucky, on November 4, residents of the strip from the Moscow region to the Kavminvod will see the covering of a bright star with a magnitude of 4, 2 m by the asteroid 20193 Yakushima. For comparison, a celestial body with 10 m is visible even through binoculars.
Also, 19 planetary conjunctions are expected - at this moment they are visible on the celestial sphere very close to each other. Already on February 8, Venus and Saturn will approach each other, they will be separated by a distance of less than half a degree. Next, February 11 - Venus with Jupiter.
And the Sun, Earth and Jupiter will be in the same plane, so the Galilean satellites of Jupiter - Io, Europa, Ganymede, Callisto - will dance along one line, ply against each other's background, and shade. This was last seen six years ago.
Diagram of an annular solar eclipse
Asteroids, comets, meteors
The brightest asteroid to be seen in 2021 is Vesta, reaching magnitude 5.8 magnitude on March 4 when it enters the constellation Leo.
The first comet discovered this year, C / 2021 A1 (Leonard), is arguably the most significant. It was discovered on January 3 in images from the Catalina Sky Survey telescope in the US state of Arizona. Then its brilliance was estimated at 19 magnitudes. It will pass very close to Venus - 4, 2 million kilometers. And most importantly, December 12 will approach the Earth by 0, 233 astronomical units, so that those who wish can look at it with the naked eye. Although, as astronomers note, predicting the brightness of comets is a thankless task. It happens that everything changes a hundred times.
Seven meteor showers will also be visible from Earth. The closest will arrive on April 22 - Lyrid. And the brightest will be Aquarids, Perseids, Draconids and Geminids.
Retrograde Mercury and the planets
In recent years, there has been a lot of talk about Mercury retrograde and its effect on the Earth. Although from a scientific point of view, the retrograde, or backward, movement of the planets is not a secret for at least two millennia. Even ancient people noticed that the Sun and Moon move across the sky from west to east, moving from constellation to constellation (they are called zodiacal). The planets do the same most of the time. This movement is called direct. And sometimes they move from east to west - backward. But this is an appearance: the real direction of the planet is not changed.
The forward and backward motion of the planets are visible phenomena. In fact, the planets do not change the direction of movement in their orbits.
Mercury and Venus are closer to the Sun than Earth. They are called the lower planets, as opposed to the upper ones such as Mars and Jupiter. The lower planets are always close to the star, especially Mercury. Perhaps that is why such increased attention is paid to him.
When Mercury is at the maximum distance from the Sun (this point is called elongation) to the west or east, it is visible to the naked eye in the morning or evening. Then, in a backward motion, he approaches the Sun and hides in its rays. Having passed between the Earth and the Sun (or behind the Sun), it moves away from it. At the same time, it seems as if he slows down the movement. At the point of elongation, the planet stops and begins a direct movement - from west to east. And everything repeats itself again.
This year Mercury met in the evening sky. It reached the eastern elongation on January 23, and on the 30th it will begin to move back in order to switch to morning elongation in February. In total, in 2021, he will have to be retrograde three times - less than in the past.
But what is really remarkable is the Bepi Colombo spacecraft flying towards Mercury with Russian instruments on board. In August, he will perform the second gravitational maneuver at Venus, and on June 23 - the first at Mercury. And it will arrive at the red-hot planet at the end of 2025.
© Astronomical calendar for 2021, compiled by A. N. Kozlovsky