The planetary alignment of a lifetime
Buckle up to witness a once-in-a-lifetime event! The planetary conjunction of Mercury, Venus, Mars, Jupiter, Saturn, Uranus, and Neptune, in that order, is set to take place between the 23rd and 25th of June, 2022, at dawn around 3:30 and 4:30 am. The exciting part is that the waning moon is also set to join the parade as it sits right in the middle of Venus and Mars.
Even though Uranus and Neptune would be joining the alignment with their fellow planets, they are not naked-eye celestial bodies (at least from a city viewer’s perspective), and so they will unfortunately not be seen, as Uranus has an apparent magnitude of about 5.3 on a good day, and Neptune has an apparent magnitude of about 7.8.
Looks like the moon is representing the Earth to give us Earthlings a wonderful sight to see as it completes the solar system.
The interesting thing about this is the difference between the alignment as seen from Earth and the alignment as seen from a bird’s-eye view of the solar system. There’s a lot of technical understanding that needs to be done when looking into how planets are viewed from the Earth.
The solar system itself can be divided into two parts (from the Earth’s perspective) — Inner and Outer planets. The inner planets constitute Mercury and Venus as they lie within the Earth’s orbit and the outer planets lie outside. As planets don’t illuminate on their own, but with the help of the Sun’s light, only at certain positions are they visible from Earth.
For example, Venus is visible when it lies on the hypotenuse vertex of a Sun-Earth-Venus right triangle. This celestial event is called the Maximum Elongation of Venus. It is the time when Venus is at its brightest, and the highest that it can be up in the sky.
Similarly, for the Outer planets to be visible, they need to lie at about a 180° line from the Earth. Because that’s when the planet itself is closest to us, and so will be at its brightest. This is what we call an Opposition — When the planet and the Sun are on the opposite sides of the Earth. It is to be noted that the Outer planets can still be visible in other positions (not as bright as during the Opposition) as well, as long as the Earth is at least somewhat in between the planet and the Sun.
So, for all the planets to align in a way that it could be visible to view from here on Earth is incredible. Conjunctions and alignments like these are less common and happen rarely. A 5-planet alignment is said to take place about every 19 years, and an all 8-planet alignment is said to take place almost every 170 years. So this indeed is a once-in-a-lifetime view for all of us, so don’t miss it.