Tag Archives: Astrology

Astronomy vs Astrology: Absolutely Not the Same Thing

About six months ago, I subscribed to a podcast called Astronomy Cast. It’s a wonderful popular science podcast about, you guessed it, astronomy & I highly recommend it. They cover anything & everything & their November episode on the zodiac inspired me to do some research & write this article.

But first, a small back story:

I’m a space nerd. It started my freshman year in college, when I needed to take a science course for my general education requirements. I’ve always liked science a lot, but there’s one problem. While I have no issue grasping the concepts, I’m terrible with numbers. Ask me to write an article on it & I’m fine, but ask me to prove theories with numbers &, well, I probably won’t prove them. I’ll probably just send you to a book or website that can. I only had to take an intro course, but even so, chemistry was out. So was physics. Even at their beginner levels, math is heavily involved. That’s when I came across Sacred Heart University’s listing of their introductory astronomy course.

I was a little apprehensive; I didn’t know what was in store for me, but it turned out to be the perfect one to take, kicking off my love affair with space. We learned about everything from the proposed history of the universe to names of stars & where they’re located in the sky.

I eventually got myself a pretty cool telescope with an eight inch mirror (I regret that I haven’t used it since my move to Boston), which can easily make out Jupiter’s cloud bands & moons, far away clouds of gas & distant galaxies. Now, I was ready to stargaze & to the dismay of others, from that moment on, I could talk anyone’s ear off about it. Pretty soon, though, I started to notice two very common responses from a concerning amount of people:

1) “It’s cool you’re into astrology, when did you get into that stuff?”
2) “Oh, cool. That’s like horoscopes & stuff, right? So, can you predict my future?”

Not to sound pretentious, but these are what I call, “head-desk” responses & soon, you’ll find out why. Before I explain it, though, I just want to say that I know people believe in certain things & while I explain this, I’m going to try to be sensitive to all the astrology lovers out there.

That’s funny. No, I’m not. Astrology is a gigantic pile of crap.  Seriously.

Okay, you get how I feel about it, so I’ll just get into the rest of the article. Astrology is a type of divination. It’s the “study” of how the locations of the different planets, sun & moon in the zodiac calendar influence your personality & daily life… blah blah blah…  There is absolutely no way any of this is true. There is plenty of evidence to support my stance, but for now, I’ll just go through the basics with you.

The positions of the constellations in the Zodiac calendar are not accurate:
This is one of the biggest points made in the “Zodiac” episode of Astronomy Cast.

The Zodiac calendar is centered around the solar ecliptic. For those of you who are wondering, the ecliptic is the line the sun appears to follow across the sky over the course of a year. In the same amount of time, the Earth travels in a complete circle, or orbit, around the sun. As we travel along the orbital path, the angle at which we observe the sun constantly changes. That means that the stars we see behind the sun change as we move through the year & your birth sign is the constellation where the sun was positioned when you were born. This is said to have a direct influence on your personality & what makes you, you.

Many of the other significant bodies in the solar system more or less follow the ecliptic as well. Astrologers believe if Mars or any other planet is in X constellation, your mood should therefore be Y. The same can be applied to the moon.

Here’s the problem with all of this. The people who invented this type of divination decided to divide up the year into twelve equal parts. Even if we disregard the fact that there are actually thirteen constellations through which the ecliptic passes, the constellations aren’t even remotely the same size & therefore don’t take up a convenient one twelfth of the ecliptic. The time it takes for the sun to appear to pass through each constellation ranges from just a few days to about forty. This means for most people, they weren’t even born under the sign they think they were & that, my friends, is just stupid.

A zodiac chart from the 9th Century, showing the 12 months versus the 12 evenly spaced zodiac signs.

A zodiac chart from the 9th Century, showing the 12 months versus the 12 evenly spaced zodiac signs.
(Photo in Public Domain)

Constellations are just shapes made up by our imagination.
Nowadays, constellations serve a purpose. Astronomers use them to find & name stars & other astronomical objects. They’re locations in the sky where we can find things. Pretty practical, right? This wasn’t always the case, though.

We know that the concept of constellations go as far back as the Ancient Babylonians, & they probably go back farther. Back in the early days of stargazing, Babylonians believed that these shapes in the sky were the deceased heroes of their culture, floating in heaven. Eventually, the Ancient Greeks adopted these stories & added their own. The Romans then added to the Greeks’ work & so on.

I like to imagine that the conversations between citizens & wise men went like this:

Citizen: Oh great one, I have a question about the stars.
Wise Man: Go ahead, son.
Citizen: How did they get there? What is that shape?
Wise Man: Well, um… uhhh, they’re dead people in heaven. See that one? That’s a ummm- hunter. His name’s Orion.
Citizen: Wow really? That doesn’t sound like a name.
Wise Man: Yeah, but it is, & see those two stars in a line that don’t look like a dog at all?
Citizen: Yes, what do they make?
Wise Man: A dog.

Anyway, they’re just imaginative & since we now know the sky isn’t a two dimensional thing, we know that the constellations’ shapes would be drastically different, if we were to look from another part of the galaxy.

They’re meaningless, aside from modern cataloging.

The pull of gravity from the planets isn’t nearly enough to affect your mood.
Jupiter is the biggest planet in the solar system. Aside from the sun, it’s the most massive object & has the most gravity. Relative to the rest of the solar system, the moon is small, but it can pull oceans. Just think what Jupiter can do. Better yet, your body is two thirds water. Just imagine what that does to your brain chemistry & physical health!

Okay, everything I just said up there is complete garbage & it’s all because of Newton’s law of univesal gravitation. One thing I will concede is that the planets of the solar system are pretty massive. With mass comes gravity, & with gravity, come tidal effects. These are what cause the oceans to rise & fall with the moon’s position. Here’s the thing about that law, though. While more massive objects have more of a gravitational influence, that influence diminishes as it gets farther away. That’s why if you send a spaceship out to, say, the moon, it will have to hit 25,000 miles per hour. That’s called escape velocity The farther you are from an object, the less you’ll feel from its gravitational pull. As you head towards the moon, Earth’s gravity wants to pull you back, making you decelerate, but if you leave Earth at 25,000 mph, its gravity won’t slow you down enough. You’ll coast, slowing down, but eventually, you’ll be far enough from Earth that its gravitational influence won’t exert enough on you to keep you back. You’ll break free. The moon’s will become stronger as you get closer to it & you’ll start to be pulled moon-wards.

Why did I give that long winded example? Well here: It also works the same way with the planets. Jupiter’s mass is about 25 thousand times the mass of the moon’s, so it’s natural to think it’d pull us towards it without a problem. That’s not true. It’s so far away (at its closest, Jupiter is 365 million miles away, compared to the moon’s 240 thousand) & Earth is so close, the effects are unbelievably tiny.

Let’s get some perspective on how small this effect is. Mars is much closer to Earth than Jupiter, at an average of distance 140 million miles. If you’re standing on the surface of Earth, Mars has the same gravitational influence as three humans who are in the same room as you. That’s almost nothing, & therefore, by astrology’s logic, every time you pass three people at a close distance, your personality or mood should change.

Astrology also assumes that each planet stays constantly at the same distance from Earth. That’s not even close to true. The planets are constantly at different distances from you. I previously said Mars is at an average of 140 million miles away. Remember, everything in the solar system is in motion & that means that depending on when you look at it, a planet could be all the way on the other side of the sun. It could also be on the same side as you. At its greatest distance, Mars’ gravitational influence would be much less than it’s closest distance. So, there’s definitely that.

Astrology constantly needs adjusting.
Remember when I said that everything in the solar system is in motion? The same applies to the galaxy. That means that every star is in its own orbit around the center of the Milky Way. As a consequence,the constellations are going to disassemble & change over time. Check out this video. Watch the Big Dipper in the middle. The stars start to move away from their familiar ladle-like shape. It’s a slow process, but regardless, there is going to come a time when astrologers need to rethink the signs.

The Earth is protected from the solar wind.
Reactions which are influenced by electrically charged particles happen all the time. This could affect the electrical charges which are being fired in our brains all the time, therefore changing our mood, right?
Some planets have electromagnetic fields, but it boils down to the same problem as before: distance. Jupiter has a disgustingly huge magnetic field. It’s so large, that we can pick its sound up on our radio telescopes, but by the time it gets to us, it’s too weak to do anything.

Rendition of Jupiter's magnetic field, or magnetosphere. Note how Jupiter's moons are surrounded, but Earth is not. Photo courtesy of Wikipedia user, Volcanopele

Rendition of Jupiter’s magnetic field, or magnetosphere. Note how Jupiter’s moons are surrounded, but Earth is not.
(Photo courtesy of Wikipedia user, Volcanopele)

The only object that can influence us with its particles is the sun, by constantly emitting the solar wind, which is a stream of charged particles. These flow out in every single direction. Guess what planet sits in one of the every single directions. That’s right, Earth. When an extra big solar flare that is aimed at us occurs on the sun, it has the capability to knock out communications satellites & power grids.
Down here, we have protection from it. That comes in the form of our own magnetic field. Our magnetic field deflects the majority of the sun’s charged particles, UV & other harmful radiation. So, aside from sunburn, dehydration & skin cancer it’s unlikely. Let’s pretend that most astrologers’ arguments are valid. There are still two things that astrologers don’t take into consideration here:

1) Even if the sun did influence our personalities, there is no reason to think that it would only influence us in the womb. We have more exposure to the sun after we’re born, so at the very least, depending on whether or not we wear hats or sunscreen, our personalities would still be changing constantly.
2) The website, Bad Astronomy’s article, “Misconceptions: Astrology” brings attention to astrologers’ tendencies to give the sun way less importance than the planets, despite the fact that the sun has much more of an influence on us in every way possible. It has 99% of the solar system’s mass. If it were to have an impact on your personality, it would be astronomically (all pun intended) larger than that of the planets’ effects combined.

So, as you can see, there is an overwhelming amount of evidence is stacked against astrology. That’s just the surface; there are countless other facts. Look, if you have fun pretending to predict the future, I won’t hold it against you at all. Just don’t expect me to follow along.

Anyway, that’s my rant for the week. I’ll be back with more records & useless information next week!

Now you know; you’re welcome.

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