The Moon will leave us a very dark sky during this weekend because the new moon will take place on Monday, July 17. So let’s take advantage to enjoy the planets, there are five visible to the naked eye and forming beautiful scenes in the sky.
The Moon will not be any obstacle to observe the three rocky planets of the solar system, brothers of the Earth, which are visible in the evening twilight, since we are on the eve of the next new moon, which will take place on July 17 in the constellation of Gemini.
One hour after sunset, it is advisable to face northwest in a place with a clear horizon and free from light pollution. Extremely bright Venus dominates the show, but a little higher (about ten degrees away) we can also see the faint reddish glow of Mars. And, between both planets, we can distinguish the star Regulus (from the Latin “little king”), the brightest of the constellation Leo, which exhibits a beautiful bluish glow.
Venus reaches its maximum brightness of the year these days as it is extremely close to Earth, just 55 million kilometers (just over a third of the Earth-Sun distance). It is so close that, with binoculars, it is possible to see the phase in which it is, with only a fine arc of the planetary disk illuminated by the Sun. We must take advantage of these days to observe it because as the month progresses, its distance apparent to the Sun will decrease and, at the end of the month, both stars will be practically aligned and will disappear together at sunset. Venus will not be visible until late August when it will reappear in the eastern sunrises.
This weekend Mars continues to appear much weaker than Venus, because in recent months, as it has traveled its orbit around the Sun, it has been moving away from Earth. It is now 2.3 times farther than the Sun and 6.4 times farther than Venus. This great distance, together with its own characteristics, now makes Mars appear a few 400 times less bright than Venus.