Planetary Alignment – What You Should Know?

Knowing where the planets are is of great importance to a few different kinds of people. For instance, those interested in astrology use the locations of planets to determine the happenings of their future. On the other hand, astronomers need this information to easily find the desired celestial body in the sky. Last but not least, some people just like to know where various heavenly bodies are in relation to the Earth.

The ancients relied on the positions of the stars to guide them on their journeys. They understood that the stars were all fixed in their positions relative to each other in the night sky. However, seven points of light marched to a tune different from their compatriots. People of the time believed that their alignments either augured good fortune or bad outcomes, depending on the exact configuration.

Cultures across the world have historically awarded special significance to the alignment of the planets and other celestial phenomena. Some individuals still carry these traditions to this day. But do planets ever align (truly)? The answer is YES and NO. Read on to find out why.

What is Planetary Alignment?

The term “planetary alignment” can refer to a few different things. It is generally used to refer to a state where two or more planets appear to be situated on a line crossing through the center of the Earth or the Sun. Other than that, this term is also sometimes used to explain “appulses” and “conjunctions”.

Appulses happens when two heavenly bodies appear close to each other in our sky. On the other hand, a Conjunction is when multiple planets share the same longitude when observed from Earth.

Planetary alignment is NOT an event in which all the involved planets lineup in a perfectly straight line. The explanation may seem reasonable for such a lining-up to happen if one is looking at a two-dimensional diagram. This is because the orbits of all the planets are represented on the same plane in such a setting.

In reality, planets exist in three dimensions and their orbits are all off-set from each other at different angles. Even if some planets appear to have lined up in a top-down view of the solar system, it’s nothing but an illusion. Switching to the side-view will reveal that all of them are at different elevations.

When will the Planets Align?

Partial alignments that require only two bodies to roughly line up within the same constellation are quite common. The definition of “appulse” can be loosened so that all the bodies are visible in the same quadrant of the sky. In this case, even appulses involving all eight planets occur as often as once every 200 years. That might seem to be a lot of time, but 200 years is barely a moment on the cosmic scale.

Calculations of Planetary Alignment

Other types of planetary alignment are far rarer. John Savard of Quadibloc calculated the probabilities of all the planets aligning with the Sun. He found that a line with planets on either side of the Sun could be formed once every 516 years. Likewise, a line with all the planets on the same side of the Sun may form once in over 1.6 million years. These calculations were made by considering the differences between the orbital periods of the inner-most and outer-most planets.

NOTE: He assumed no variation in planetary position along the third dimension.

When is the Next Planetary Alignment?

In astronomy, the term “great conjunction” is used when Jupiter and Saturn share the same longitude when observed from Earth. The next planetary alignment will be a great conjunction that is expected to occur this year at Christmas. On 21st December, the two planets will appear so close to each other that they will become indistinguishable to the naked eye.

This will be the first great conjunction since 2000, and the closest one since 1623. At their closest, the two planets will be only 0.1 degrees apart. They will be separated by a patch of sky no wider than a fifth of the diameter of a full-moon. Astronomers believe that Jupiter and Saturn won’t be this close again until 15th March 2080.

What to Look for While Observing Great Conjunction 2020?

Viewing the phenomenon through binoculars, you will be able to see them as separate points of light. On this occasion, Saturn will be slightly higher and much fainter than Jupiter. You might be able to observe Saturn’s rings and Jupiter’s belts by viewing this planetary alignment with a telescope. Jupiter’s four Galilean moons and Saturn’s largest moon, Titan, should also be observable during this celestial event.

The phenomenon will occur low in the southwestern horizon and will be observable in the early evening hours. An unobstructed view in that direction will be necessary for it to be seen. However, EarthSky clarified that you don’t need to wait until December to get a look at the planets. They will be visible on all nights through the rest of October till the end of this year.

Current Planetary Alignment

According to The Planets Today, the positions of the planets are as follows (at the time of writing this article). Mercury, Mars, and Uranus are close to a line passing through the centers of both the Earth and the Sun. Venus, Jupiter, and Saturn are to be found on a line roughly perpendicular to the afore-mentioned one. Venus is on one side of the Sun while both the gas giants are on the opposite side. Lastly, Neptune is located between the two lines on the Jupiter/Saturn side.

Current Locations of Planets

Venus is currently in the constellation Virgo. Uranus is in Taurus, Mars is in Aries, and Neptune is in Pisces. Jupiter and Saturn are both in Sagittarius and Mercury is in Scorpio. Actually, Mercury may have moved to some other constellation since I began writing this sentence, but let’s not get into the technicalities.

Frequently Asked Questions (FAQs)

Q. How often do Jupiter and Saturn align?

A. Jupiter completes one orbit in about 12 Earth years, whereas it takes Saturn about 30 years to do the same. Hence, it takes about 20 years for a Great Conjunction to occur. It happens when Jupiter moves far enough in its 2^nd lap (around the Sun) to be positioned next to Saturn. Quite obviously, Saturn is still in its first lap at that time.

Q. Can Planetary Alignments Cause Earthquakes?

A. Many people believe that the planets lining up with the Earth and the Sun will not bode well for us. It is quite common to encounter rumors (with certain dates) about an alignment that will cause the world to end. Mostly, the supporting reason provided is that the accumulative gravitational effects of the planets will cause great earthquakes. However, there is nothing much in it, scientifically.

The fact is that planets are either too small or far too distant to have any significant effect on Earth. Even if all of them are simultaneously at the least possible distance from us, it won’t create a problem. According to calculations, the strength of their combined gravities on Earth will be less than one-sixtieth that of the Moon. Therefore, there are no chances of earthquakes, big or small, being caused by planetary alignments.