During the second half of February we can observe how Venus and Jupiter are getting closer to each other to, at the end of the month, form one of the most beautiful planetary conjunctions of the year.

cosmic clock

Like pieces of an ultra-precise cosmic clock, the planets of the solar system follow their orbits punctually and inexorably.

In the sky we can always see them along the ecliptic line, crossing the constellations of the Zodiac.

And on this imaginary line the multiple encounters between them take place, and often also with the Moon, thus creating the astronomical conjunctions that have fascinated humanity since the origin of civilizations.

Particularly spectacular are the conjunctions between Venus and Jupiter.

And it is that, after the Moon, Venus is the brightest star in the night sky, and Jupiter is often the second brightest (Mars can unseat it from this place during some of its oppositions).

After the sunsets of the remaining days of February we can follow the course of the two bright stars in the sky and enjoy the gradual approximation of their apparent positions, an approximation that will culminate in the conjunction from February 28 to March 2.

Let's look up to the west a couple of hours after sunset.

In the middle of the month, Venus and Jupiter appear separated by an angular distance of about thirty degrees, this is equivalent to the size of a fist with the thumb raised, when we extend our arm.

Both are now in the constellation of Pisces, very close to the Whale.

The stars that are close to the planets are not particularly bright.

If we are in the city, it is very possible that we can only distinguish the brightness of the two stars, without visible stars in their surroundings.

However, to your right, as we look at the sky, we can see the great square of Pegasus.

Between Tuesday the 21st and Thursday the 23rd, the distance between Venus and Jupiter will have reduced, and the pretty edge of the crescent moon will come to visit them.

The most peculiar scene will take place on the 22nd, when the Moon is in the middle position between the two planets.

We must take the opportunity to observe the ashen light on the surface of our satellite: it is caused by solar radiation that reaches the Moon after reflecting on the Earth (it is the reflection of a reflection).

The sky on February 28 Stellarium/RB

The distance between Venus and Jupiter will continue to shrink until the end of the month when it is just over a degree.

So the two bright spots will look like a double planet.

But let's not fool ourselves, although the apparent positions in the sky of both stars are very close, the distances of Venus and Jupiter from Earth are very different.

Venus is now about 205 million kilometers away, while Jupiter is more than 850 million kilometers away.

Despite being more than four times as far away, Jupiter is 1,500 times larger than Venus.

Taking into account the illumination of both, it turns out that the brightness of Venus is now about five times more intense than that of Jupiter.

Due to the regularity of the planetary movements around the Sun, Venus and Jupiter are in conjunction once a year.

However, in 2024 the conjunction will not be visible, since it will take place in a position very close to that of the Sun. It will be necessary to wait until August 2025 to be able to observe a comparable conjunction, then the approximation will take place at dawn, with the two stars separated by less than one degree.

Observing the course of the planets in their movements ordered by the sky reminds us that we are part of a wonderful solar system.

Let's take advantage of the cold February nights to admire the calm path of the two brilliant evening stars.

Rafael Bachiller is director of the National Astronomical Observatory (National Geographic Institute) and academic of the Royal Academy of Doctors of Spain.

According to the criteria of The Trust Project

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