Astrology, a Practical Test: Objects That Affect You at Birth

I usually don’t like making grandiose statements ahead of myself, like “Astrology is totally unscientific”, because I prefer leaving the benefit of the doubt until I check the claim. In the case of Astrology, however, there’s no use pretending.

Astrology isn’t science. It makes baseless predictions, relies on overly-generalized statements and has a false basic premise*.  You can read this online from various other sources, and there isn’t much use for me to reiterate the points made.

Picture by joelwillis via Flickr (Creative Commons 2.0)

What I am going to do is test the basic premise.

* Phil Plait, “The Bad Astronomer”, has a great analysis of Astrology that goes over all the above, and more, as does the skeptic dictionary and the Astronomical Society of the Pacific among many, many others. You can also watch Australian Skeptics’ Richard Saunders brief live argument with an Astrologer.

Note: For your convenience (and due to popular demand), I added an automatic tool where you can measure the force applied by any object at any distance. Test it yourself!

Click here to open the Force Calculator!

(opens as a new window).

The basic premise of astrology

Astrologers claim that the positions of the planets and “Zodiac” signs (constellations of stars) at the moment of our birth – and generally throughout our lives – affect our personality, mood and affairs.

I will not get into the so-called  “metaphysical” effects, a mishmash of misunderstood physical theories (quantum physics, dark matter, dark energy, etc) with some pseudoscientific new-age unfalsifiable claims (from “fate” and “luck” to “planetary energies”, whatever that means). What I will do is treat the claim that astrology has merit in science. Many astrology-believers think that since the planets exert gravity, they might affect our brains, and therefore our moods.

Many people give the moon as an example. The moon’s gravity is known to affect tides – a powerful force we can witness. Many take this as proof that the planets’ gravity is affecting our bodies. On its face, the claim makes sense.

We are going to examine it.

Gravity, the force of masses

Any two objects with mass exert gravitational force on one another. That force is related to the masses of the objects and the distance between them by the formula:

F= G \frac{M, m}{r^2}

left( G=6.67\cdot 10^{-11} \frac{mbox{m}^3}{mbox{kg} \cdot mbox{s}^2} right)

Where G is the universal constant of gravitation, M and m are the masses of the objects and r is the distance between them.

Since we think of planets as incredibly big objects, the idea that their gravity affects our bodies sounds reasonable. But to a newborn, there are other “massive” objects around that exert the same type of force as the planets. They might be much smaller than the planets, but they are much closer, too. If the position of planets at the moment of our birth defines our personality, so should the positions of objects in the delivery room.

This is a testable claim.

The test: planets vs. delivery room

We are going to compare two forces, those coming from the planets and those coming from objects in the delivery room, to reach a conclusion:

  • If the forces from the objects in the delivery room outweigh those from the planets, then astrologers should, at the very least, ask the weights and positions of the people in the delivery room when they calculate your chart.
  • If, however, the forces of the planets are substantial, then astrology might have some scientific merit. This is what we are about to check.

OMG! Math! Panic!


We are about to calculate physical forces so there is some math involved, but you can choose if you want to see it or not. Yes, I’m that considerate.

If you want to go over my math so you can repeat it yourself, add to it (items I missed?) or criticize me (peer-review away, mathematicians) you can reveal the calculations by clicking the “Show the Math” links.

Otherwise, just continue reading the solutions only. Those are useful too.


One more note: Forces are directional (vectors), but in this case, since we want to calculate the maximum possible force, we will treat them as if they are “lined up”, and therefore calculate them numerically.

What about the mother?

Right, the mother is also in the room, and her body also exerts a gravitational force on the baby. However, The baby is inside the mother, and in her midsection. He is, almost literally*, in her center of mass. For all intents and purposes the mother’s gravity “cancels out” from all directions and there’s no use adding her into the calculation.

* Physicists, stay calm, think “spherical chicken in a vacuum” and bear with me here.

On we go.

The delivery room

Since my intent is to calculate the most basic hospital delivery room, I put in the most basic items that should be found in one. There are likely many more people and pieces of equipment in and outside the room, but the goal of these calculations is a “conservative estimation.”

Therefore, I will ignore the size of the hospital, other people walking by and other large machines that exist in the building. See “Conclusion” for more about those.

Here’s a list of what should be the most basic elements in a delivery room:


  • A doctor (obviously)
  • A nurse
  • OB tech (whose job is to help the doctor and nurse during the actual birth)
  • The partner (assuming the mother has one)


The Calculation

In the following section I will calculate the force exerted on the baby from each of these elements by estimating their weight and mass and their relative distance.

I will assume average-sized staff (75-85 kg), leaning towards the thinner side, to keep my estimate conservative. I will also assume that the baby is level with their midsections (i.e., their centers of mass) which will allow me to ignore their height in my calculation.

Show the Math

The Doctor

The doctor stands directly in front and above the baby before it is born. If anything affects the baby, he is it.

  • Mass = 82 kg
  • Distance from baby = 0.3 m (30 cm)

F_{doctor}=G\frac{82 kg \cdot 3.6 kg}{(0.3 m)^2}=(6.67\cdot 10^{-11}\frac{m^3}{kgcdot s^2}) \frac{295.2 kg^2}{0.09 m^2}=2.19\cdot 10^{-7} \frac{m\cdot kg}{s^2}

The force exerted by the doctor’s gravity = 2.19\cdot 10^{-7} N

The Nurse

  • Mass = 75 kg
  • Distance from baby = 1 m

F_{nurse}=G\frac{75 kg \cdot 3.6 kg}{(1 m)^2}=(6.67\cdot 10^{-11}\frac{m^3}{kg\cdot s^2}) \frac{270 kg^2}{1 m^2}=1.8\cdot 10^{-8} \frac{m\cdot kg}{s^2}

The force exerted by the nurse’s gravity = 1.8\cdot 10^{-8} N

The OB Tech

This person will be standing next to the instruments, monitoring the delivery. He will likely be a bit further away than the doctor and nurse.

  • Mass = 80 kg
  • Distance from baby = 3 m

F_{OB Tech}=G\frac{80 kg \cdot 3.6 kg}{(3 m)^2}=(6.67\cdot 10^{-11}\frac{m^3}{kg\cdot s^2}) \frac{288 kg^2}{9 m^2}= 2.13\cdot 10^{-9}\frac{m\cdot kg}{s^2}

The force exerted by the OB Tech’s gravity = 2.13\cdot 10^{-9} N

The Partner

  • Mass = 80 kg
  • Distance from baby = 0.5 m

F_{Partner}=G\frac{80 kg \cdot 3.6 kg}{(0.5 m)^2}=(6.67\cdot 10^{-11}\frac{m^3}{kg\cdot s^2}) \frac{288 kg^2}{0.25 m^2}= 7.68\cdot 10^{-8}\frac{m\cdot kg}{s^2}

The force exerted by the partner’s gravity = 7.68\cdot 10^{-8} N

Bed or Birthing Chair

  • Estimated mass: 276 lbs = 125.19 kg
  • Estimated distance: 0.05 m (5 cm)

(Source: this isn’t a birthing bed, but it’s close enough for an estimate)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 125.19 kg}{(0.05 m)^2}= 1.2\cdot 10^{-5}\frac{m\cdot kg}{s^2}

The force exerted by the bed’s gravity = 1.2\cdot 10^{-5} N

Heart Monitor

  • Estimated mass: 25 kg
  • Estimated distance: 1 m

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 25 kg}{(1 m)^2}= 6\cdot 10^{-9} \frac{m\cdot kg}{s^2}

The force exerted by heart monitor’s gravity = 6\cdot 10^{-9} N

Scale (to weigh the baby)

  • Estimated mass: 3.6 kg
  • Estimated distance: 3 m

(source: this is a small version, good enough for our calculation, but it’s worth noting most hospitals will carry a much larger one, on wheels, obviously weighing much more).

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 3.6 kg}{(3 m)^2}= 9.6\cdot 10^{-11} \frac{m\cdot kg}{s^2}

The force exerted by the scale’s gravity = 9.6\cdot 10^{-11} N

Blood pressure monitor, Stethoscopes and other random small items

There are a LOT of items in a delivery room, and I am very likely to forget a whole bunch of them. We will estimate, though, a total of 5 kg of extra random items like more chairs, the blankets and sheet, stethoscopes, blood pressure monitors, picture frames, and anything else that might exist in a room and didn’t add into the calculation. This is a very very conservative calculation.

I will take the average distance of all of those random items as 4 meters.

  • Mass = 5 kg
  • Average distance from the baby = 4 m

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 5 kg}{(4 m)^2}=7.5\cdot 10^{-11}\frac{m\cdot kg}{s^2}

The force exerted by the random items’ gravity = 7.5\cdot 10^{-11} N

Total Maximum Force

So, to summarize (and, for those of you who cared not for the mathematics, to state in the first place):

  • The Doctor = 2.19\cdot 10^{-7} N
  • The Nurse = 1.8\cdot 10^{-8} N
  • The OB Tech = 2.13\cdot 10^{-9} N
  • The Partner = 7.68\cdot 10^{-8} N
  • The Bed = 1.2\cdot 10^{-5} N
  • Heart Monitor = 6\cdot 10^{-9} N
  • Scale = 9.6\cdot 10^{-11} N
  • Other Small Objects = 7.5\cdot 10^{-11} N
Show the Math
  • From people: 2.19\cdot 10^{-7}N + 1.8\cdot 10^{-8} + 2.13cdot 10^{-9}+7.68\cdot 10^{-8} N = 3.1593\cdot 10^{-7}
  • From objects: 1.2\cdot 10^{-5}N + 6\cdot 10^{-9}N + 9.6\cdot 10^{-11}N + 7.5\cdot 10^{-11}N=1.2006171\cdot 10^{-5}

Total Force: 1.232cdot 10^{-5} N

The Planets

EDIT: I have recalculated the forces from the planets. It seems that during the initial calculations I made a rather small (but recurring) conversion error, and due to vigilant commentors, it was properly corrected. You should note, though, that the total force after this re-examination didn’t change. My calculation was fine, I just had a problem with how I wrote it out in the process (in the math part). Apologies.

Now, astrology claims that the planets exert a force on the baby, and their different locations change that force ever-so-slightly to somehow affect the baby’s personality traits.

The idea that the planets exert a force, even on the baby, is true. Whether or not it is canceled out or overwhelmed by other forces is a different issue.

Our next step, then, is to calculate the maximum force that can be exerted from the various planets, and combine them to get the maximum possible force exerted by the planets.

Show the Math


  • Mass: 0.3302\cdot 10^{24}kg
  • Minimum Distance from Earth: 77,300,000 km (7.73 \cdot 10^{10} m)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 mbox{kg} \cdot 0.33\cdot 10^{24} mbox{kg}}{(7.73\cdot 10^{10} m)^2}=1.33\cdot 10^{-8}\frac{m\cdot kg}{s^2}

Maximum Force by Mercury = 1.33\cdot 10^{-8} N


  • Mass: 4.85\cdot 10^{24}kg
  • Minimum Distance from Earth: 38,000,000 km (3.8 \cdot 10^{10} m)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 4.85\cdot 10^{24} kg}{(3.8\cdot 10^{10} m)^2}=8.06\cdot 10^{-7}\frac{m\cdot kg}{s^2}

Maximum Force by Venus= 8.06\cdot 10^{-7} N


  • Mass: 0.642\cdot 10^{24}kg
  • Minimum Distance from Earth: 54,600,000 km (5.46 \cdot 10^{10} m)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 0.642\cdot 10^{24} kg}{(5.46\cdot 10^{10} m)^2}=5.17\cdot 10^{-8}\frac{m\cdot kg}{s^2}

Maximum Force by Mars= 5.17\cdot 10^{-8} N


  • Mass: 1899\cdot 10^{24}kg
  • Minimum Distance from Earth: 893,000,000 km (8.93 \cdot 10^{11} m)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 1899\cdot 10^{24} kg}{(8.93\cdot 10^{11} m)^2}=5.72\cdot 10^{-7}\frac{m\cdot kg}{s^2}

Maximum Force by Jupiter = 5.72\cdot 10^{-7} N


  • Mass: 568\cdot 10^{24}kg
  • Minimum Distance from Earth: 1,195,000,000 km (1.195 \cdot 10^{12} m)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 568\cdot 10^{24} kg}{(1.195\cdot 10^{12} m)^2}=9.55\cdot 10^{-8}\frac{m\cdot kg}{s^2}

Maximum Force by Saturn = 9.55\cdot 10^{-8} N


  • Mass: 86.8\cdot 10^{24}kg
  • Minimum Distance from Earth: 2,580,000,000 km (2.58 \cdot 10^{12} m)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 86.8\cdot 10^{24} kg}{(2.58\cdot 10^{12} m)^2}=3.13\cdot 10^{-9}\frac{m\cdot kg}{s^2}

Maximum Force by Uranus = 3.13\cdot 10^{-9} N


  • Mass: 102\cdot 10^{24}kg
  • Minimum Distance from Earth: 4,400,000,000 km (4.4 \cdot 10^{12} m)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 102\cdot 10^{24} kg}{(4.4\cdot 10^{12} m)^2}=1.27\cdot 10^{-9}\frac{m\cdot kg}{s^2}

Maximum Force by Neptune = 1.27\cdot 10^{-9} N


I am including it in because astrologers do, too.

  • Mass: 0.0125\cdot 10^{24}kg
  • Minimum Distance from Earth: 4,200,000,000 km (4.2 \cdot 10^{12} m)

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 0.0125\cdot 10^{24} kg}{(4.2\cdot 10^{12} m)^2}=1.7\cdot 10^{-13}\frac{m\cdot kg}{s^2}

Maximum Force by Pluto = 1.27\cdot 10^{-13} N

The force from all the planets combined

All of the forces above were calculated as if the planet is in its closest position to the Earth. The chances that all planets together will be in such positions are incredibly small. This doesn’t usually happen, and the resultant combined force is much smaller. However, we can still calculate the maximum theoretical force that can be produced by all planets combined on the newborn baby.

Here they are:

  • Mercury = 1.21\cdot 10^{-8} N
  • Venus = 8.06\cdot 10^{-7} N
  • Mars = 5.17\cdot 10^{-8} N
  • Jupiter = 5.72\cdot 10^{-7} N
  • Saturn = 9.55\cdot 10^{-8} N
  • Uranus = 3.13\cdot 10^{-9} N
  • Neptune = 1.27\cdot 10^{-9} N
  • Pluto = 1.27\cdot 10^{-13} N

(Before you protest about Pluto, read this: there are many problems with including Pluto in the calculation of gravity – the least of which is his “partner” Charon, who’s of similar mass. However, Astrologers calculate Pluto into their maps, and so I thought it would be appropriate to include the force it exerts, too.)

Show the Math

1.33\cdot 10^{-8}N + 8.06\cdot 10^{-7}N + 5.17\cdot 10^{-8}N + 5.72\cdot 10^{-7}N + 9.55\cdot 10^{-8}N + 3.13\cdot 10^{-9}N + 1.27\cdot 10^{-9}N + 1.27\cdot 10^{-13}N=1.5442\cdot 10^{-6}N

Total Force = 1.54297\cdot 10^{-6}N


So, what do we have?

  • The combined forces of the delivery room = 1.232\cdot 10^{-5} N
  • The combined forces of the planets = 1.544\cdot 10^{-6} N

Difference =\frac{1.232\cdot 10^{-5} N}{1.544\cdot 10^{-6}} = 8.01

The forces from the delivery room are 8 times bigger than the combined force from the planets, and we have calculated a very conservative estimate.

Proponents of the claim might jump out of their seats and claim the forces are extremely close. They seem close (if a factor of 8 is considered close) but we have to remember a few important issues that show conclusively that the forces from the planets are minuscule compared to the forces exerted on the baby from his immediate surroundings:

  • The planets do not, ever, line up where they are all as close to Earth as our calculation asserted. The realistic force from the planets is lower.
  • Our estimates for both the distances, the amount of people and their weight was very conservative. In reality, hospitals have a lot more people and staff, much more equipment in the room and directly outside of it.
  • Hospitals are huge places. If planets as far as a few billion kilometers exert force on our newborn baby, the MRI machine (that weighs 50-60 times the weight of the doctor, nurse and OB Technician combined) at some floor below, and the CT machines somewhere in the hospital should be taken into account as well. Those would dramatically increase the difference between the two forces.
  • And, one of the most notable point of all: We ignored the Earth’s gravity!

We ignored the Earth’s gravity!

To be fair, I ignored the Earth’s gravity in both cases, for a very good reason: it absolutely trumps both. Since it is also coming from the ground, and the other forces are spatially distributed, my goal was to show that even without gravity, the difference exists, and is indeed noticeable.

But the Earth’s gravity is important here.

The Earth isn’t a perfect sphere; its radius varies from 6357 km to around 6378 km.

Assume the baby is 6360 km from the center of the Earth.

Show the Math

F=6.67\cdot 10^{-11}\frac{m^3}{kg s^2}\frac{3.6 kg \cdot 5.974\cdot 10^{24} kg}{(6.36\cdot 10^{6} m)^2}=35.46 \frac{m\cdot kg}{s^2}

In this case, the force exerted on him by gravity would be 35.46 mbox{N}

As you can see, this is 10^6 times more than the forces exerted by the occupants of the delivery room, and 10^7 times more than the force exerted by the planets together. It’s a powerful force, gravity.

And there’s more. The Earth’s gravity isn’t constant. It varies across the surface of the planet (as the radius varies). We usually use the average rounded number for the gravitational acceleration (9.806 mbox{m}/mbox{s}^2) but in different locations on the Earth, the number varies.

If the claim astrologers make is that the force from other planets affect a baby’s personality – and we’ve seen how small that force is! – then the change in the Earth’s gravitation should have an effect too. In this case, Astrologers should consider the location and elevation of your birth as well as the date and time, to calculate the variations in the Earth’s gravity.

The next time an Astrologer offers to calculate your chart, you should reminder them about that.

One more thing: The Labor Itself

We didn’t include this part in the initial calculation, but this is definitely something that we should take into account, since this is likely to be quite a powerful force.

A baby doesn’t just “walk out” of the womb, it is pushed out by the mother’s muscles. If you see any TV shows at all, you know that at the moment where the baby – and doctor – are ready, the doctor will ask the woman to “Push!!” resulting in the baby’s head being pushed out (if all is well) and the doctor assisting the baby the rest of the way.

This “push” and the movement out of the woman’s womb also exert force on the baby. On top of that, there is usually a large amount of time during which the woman’s body exerts force on the baby before it actually comes out. This would apply pressure on his body; obviously, it’s not enough to harm the baby, but it definitely exists. And labors can be long… long and tedious processes. Ask your mother how long she was in labor.

So for a large number of hours (36 is the average!) the baby is subjected to pressure from the mother’s contractions, and then to the force that pushes him or her out of the womb.

So.. why don’t Astrologers ask how long your labor lasted?


There are many things that are plain false in the claims that Astrologers make, and many blogs and sites covered the reasons why. Now, though, you could see for yourselves how the basic premise – that planets’ positions, affect the personality trait of a newborn baby – is just silly.

If the planets’ positions affect the baby’s personality traits, so should the Doctor’s position, the OB Technician, the position of the heart monitor, the CT machine down the hall and the size of the hospital and the amount of people in it.

So, unless Astrologers are willing to take these components into account when they produce your “Chart”, it seems their claims are plain silly.

And you should tell them that.

Do you have more objects to test?

Now you can. Due to popular demand, I’ve prepared a small tool to help you calculate the force from object at any distance. Play with it, and share your findings in the comments!

Click here to open the Force Calculator!

(opens in a new window).



Once again, thanks goes to:

  • Capn_Refsmmat, for some language issues, for his mastery of the LaTeX plugin and for his math peer-review.
  • Daniel Grrrrrr for his English support and patience. Lots of it.
  • UnintentionalChaos (from for some math peer-review and clarity correction issues.

astrology is based on speculation and statistics. you better realize this; there is no effect of moon's gravity on a tiny droplet of water but only on the huge tides of the sea. likewise it is not about gravity at all, astrology is more about field like influence and cosmological waves that may depend on the massive structure of constellations and planets, that affects not just an individual person but to a unit of as many as there are present. you see, newton theory which you bravely wrote to justify your point is just a fundamental understanding of gravity, we human beings have not yet unfolded all the dynamics of gravity. they just recently verified that gravitational waves existed, otherwise they only had field of influence. people like you are just thugs who puts their judgement with limited understanding on something. science is not just about numbers,verification and proof you silly , it is about possibilities. 


I will always sit on the fence in any debate until the observed probability coincides with the theory. However, the simplistic nature of this calculation in that it estimates the forces at time of birth is very flawed. THE REAL THEORY TO THE TEST SHOULD BE.... The gravitational effects on brain development until brain is full sized and whether or not the date of commencement of embryo fertilisation and the proceeding course of development and therefore inherent personality traits (not environmentally acquired superficial traits), even after birth, is dictated by gravity.

Furthermore... There are other possible tests to consider as to what causes the similar personalities of individuals who are born at similar times... Other environmental stimulus to the mother such as amount of light received, natural serotonin levels as a result of time of year etc etc. There are simply way too many variables to consider what affects the development of an embryo in the womb. It is not a closed system, nothing in nature is; in one way or another everything is causally connected.

It should not be overlooked how zodiac signs do hold truth in generalised personalities... But as for the mechanism behind it... I would like to believe it is due to a multitude of factors including gravitational affects, most part from the moon as is the strongest felt immediate to earth, but also of the entire universe and plausibly infinite multiverse (dark matter to which i postulate is cross over gravity from other branes)... I mean, even the simplest of things such as the mothers diet can have untold affects on the neurochemical dependencies of a childs brain and thus directly affect behaviour and personality.

The earth's orbit is the common answer as is what dictates seasons, times of year on earth etc etc. And is what is suggested fundamentally by astrology, as well as planetary positions.

To conclude, there is much we are deaf-blind to in the fundamental mechanisms of nature/existence itself. We will never fix our monochromatic sight for that of colour, we simply cannot, we are a part of existence, not standing on it lookin down.

It's hard to accept that we will never know anything, which is why we use the most observed probable outcome to decide anything... Which ultimately breaks down given enough time. Time is all there is...

So let is utilise our time more effectively in creating a sustainable world for us all and furture habitats to come, united in such an obvious common goal.


Astrologist will not accept (understand) this explanation with gravity stuff. They juste believe in a unknown force, not discovered by scientists... You can't convince them with logic 


@EricLorio fortunately, astrology has been studied for hundred of years, great astronomers, mathematics, philosophers from the past all used astrology and tried to explain at some level, but without too much effort from the scientific community since the 17th century, they tried to make astrology seems rather unconventional for the new age as reasons takes places instantly. But as the times comes, people will realize the fact astrology is indeed real and needs consideration from the ignorant scientific community of the now.


Hi great art! i'm so excited and i add "Like" (facebook) to

Abdul Sovey
Abdul Sovey

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Moneypoo, I love your entire page. This discussion is interesting, but I love you for having a force calculator.

I work for NASA, but I'm also a Wiccan... (lots of Wiccans love astrology). I love science, and I love Unexplained things. My more rational witchy friends usually say astrology is a "mythological system, more comparable to literature than to astronomy." However, I have also known astrologers who hate astronomers and science in general... (I argued once with the columnist Rob Brezny)... sigh. But I think those tend to be the ones who never bothered to actually study science much, or who think astronomers spend much energy or time worrying about astrology at all. (I don't know any who do.) I suppose astrology and astronomy could exist just fine if astrologers would stop calling what they do "scientific." It just doesn't hold up in that way. But it includes some lovely symbols.

Tom the Numerology Guy
Tom the Numerology Guy

Numerology is using numbers to determine and predict things about your life and coming events. While not as publicly accepted as other sciences, many people believe there are recurring patterns in life that can be seen in studying numbers and then used to predict things that have not happened yet.

You can get a numerology reading to see what numbers say about your own life.

Sandra Langstaff
Sandra Langstaff

Great way to demonstrate what reasonable folks have known all along, but (sorry) there is an easier way, with no math necessary (no offence, math!) Here it is: TWINS! We all know twins, and we know that they are born together (albeit a few minutes apart). Why don't they share a fate? We know that their *fate* or life events which happen beyond their control are very different. How is this possible, given that according to astrologers they are born under all of the same important astronomical signs / events / gravitational pulls / alignments? Of course, my being a twin helped lead me to this exact conclusion, as I cringed every time astrology was cited as a factor in my life or my sister's life - since while these proclamations were being stated, I was watching different factors impact myself and my twin. Now, if what I witnessed had 'matched'', for example if we both received bad news on the same day, had a strange visitor on the same day, won money on the same day, etc. I would have become the strongest supporter of astrology. But of course that didn't happen, and the only interesting thing about being a twin has to do with being alike genetically, which is all about science not superstition. Great article, keep up the good work!


mr astrologer ,

since you belive in rekhi and all this stuff and you also being an astrolger , you must be aware of indian vedic astrology which is another animal altogether to confuse the already belivers and practioners of astrology. when tradional and classical vedic astrolgy which is claimed to be written by ancinet sages of india ( by the way they dint consider neptune, uranus, pluto atall ) failed in predicting things , some new technique was started by the name of KP astrology which said it was devloped because the man who devloped saw differnce in lives of identical twins who had the same birth chart , and he figured out that every chart is unique and is only made for 1 person in 25000 years in heaven , and what differnce was made in the destiny of twins was matter of some seconds which changed the constellation in which they were born completely and so did there future . this system has become popular now in india and now previously failed astrolgers are learning this and claiming that now they can pin point exact predictions .

even when this attempt failed , some new man has started something called cuspal interlink theory which says that its just not the sub lord of the constellation but the sub sub lord of the constellation has something to do in the results ,they ask some important events in your life like your marriage birth of your child death of you mom and dad day you got a job and do some birth time rectification and check it with your time and come to a precise time which match according to the time and date of the events you mentioned and then according to that time cast your chart and then make future predictions which they claim to be true . they take blind charts and study them and predict exact events happened in a persons life on a given day and , date and year . so now this new system is about to make a wave , and iam sure in some another years another new system will come which will say its actually when a women concieve a child that exact second when the sperm enters is required to predict exact future of the child .

you being an astrologer can you claim that a 10 year old now can be a prime minsiter or president of the country in comming 30, 40 , 50 , 60 years ? can you predict the magnitude of ones poverty and ones richness in the chart by telling that some 1 will earn exact amount of dollars ?

by the way how are sure astrologers are that jupiter gives wisdom and power in life and saturn gives misery when it is badly placed in some sign or some constellation or some cusp or some sub cusp or some other sub sub sub cusp . who has told you guys that saturn will no matter what behave this way ? ok lets say some sages who were super amazing and had some great powers in them like christ, buddha saw it some 2000years ago , and what is the proof that this so called amazing wisdom about saturn , mars and venus is passed on to you and your community is 10000000000% accurate , unadulterated ? neptune , pluto and uranus is simply not taken into consideration in indian vedic astrology , they say they dont matter and if it is so then why not ? the sages dint see that in comming years this planets will be discovered ? and if yes then why dint they predict them that they will be discovered and passed on a message to future genreations that pls that time predict this and this and this according to there nature and so called infulence on human beings ? .

so astrologers blame nodes, saturn, mars, and some bad affilacted venus, and moon or any planet which is the lord of 7th house . while in west uranus and pluto along with this other planets are also bashed up because the poor planets were looking or aspecting or were in your 7 house . and on what grounds you made friendships of sun and mars ? and make a nuclear war like situation between saturn and sun ? why does sun represent father and not uncle ? why is mercury planet of communications? and why pluto is not a planet of romance ? .

antioxidants found in fruits are same in usa, uk, india and africa but just the divorce planet becomes differnt in differnt countries . some say 1 particular type of casting a chart is perfect while others say its not just the house and planets its the constellation that matters . why as a great enlightened community under the guidance and information passed by some highly evolved sages dont come to 1 particular conculsion atleast? maybe because it cant come and will never come because by the time if atall it will come then some new system will be found by some 1 who will say predictions are going wrong manytimes because global warming has made some planets change their mood considering poor earth which is warming up .

enough of all this from my side this was a long long post if no 1 can predict why i wrote so manythings is because my mercury must be quite strong because being a planet of communications and being in an exalted state i t made me just go on and on and on or maybe MR ASTROLOGER can tell exactly if it is mercury , saturn or pluto ?????? what say ?



Budism in established 2500 years before, and even nowadays exist Master -to - disciple lineages - few different! That is not "new age" - the provide studing , not just believe, and ways to develop new levels of conciounes and new skills!

like this - , education and faite is not the same! But six yogas of Naropa is advanced techniks.

Reiki is more accessible and it found in Japane in 1922 by Japanese Buddhist Mikao Usui. It is irrelevent to classify this things to "new age", and they worked, much more than relaksation.

For me astrology is proven by my experience. And one ot the ways is you also to have this experience, if you want - even for fun:)))


It is not the gravity considered in Astrology, and we do not live onli in 4 dimensions.

Even in modern phisics is considered multidimensional Universe , and ancient Sages and Iniciated know it. And also with esoteric education can be developed senses for this...other "dimensions" - and this schools existed thounsands years befor Oxford and Harvard universities to be found.

You mass/gravity calculations are irrelevant, that is not the point. Influences of planest are mainly from spiritual nature...

"Luminous beings are we, not this crude matter," Yoda

I made chart-readings of peoples which never met in live and they been surprised how exact the things said for then are!

If you are a real scientist , give your data fere and see what a person who you never met in live can tell for you based on your astro chart - completely free of charge!

Karl Withakay
Karl Withakay

What happens if you rotate the bed 180 degrees right before the baby is born? Do astrologers take that into account?


I think the notion that it's the gravity of the planets that affects the personality is an attempt by astrologers to attach a physics-based aspect to their beliefs, since this is what science demands of them. The argument of course is absurd, since as you said the gravity of all objects around us (even in the 9 months of pregnancy) have far more effect. Even if you were to make up the fact that they DID have significant pull, every time you turn your body you are reorienting yourself with respect to the planets. If the moon is in front of you, when you turn around it's now behind you. As you go about your day the overall effect of these ever-changing gravitational pulls would blur into an even mush of omnidirectional pulling. Of course, even if you kept somebody completely locked in position for their entire pregnancy, it's a COMPLETE leap of made-up, unproven (and conveniently unprovable) theory that gravity in any way will affect personality. And this is the problem - astrology has the ability to shift it's arguments and theory at will, much as the origin of astrology probably never talked about gravitation pulls - this is a new twist conveniently added on a whim based on a scientific attack. The bigger problem is that as scientist we're trying to argue away somebody's belief systems. There's simply no end to the counter-arguments that will be easily acceptable to those who believe, no matter how improbable or plain silly. They are literally willing to accept the completely absurd arguments (see above) in order to maintain and justify their beliefs. The problem though is that as science tries to dismantle these belief systems, we end up accomplishing the exact opposite of what we intend. We desire to turn people off of their beliefs though scientific proof, and show them that the way of science is superior, but what ends up happening is that they a) end up clinging even more tenaciously to their beliefs, b) they discard what little critical thinking they apply to their beliefs and c) begin to distrust and despise science and the scientific method because it is now a threat to them. They start to separate themselves from the 'elitist science-types' and begin a war with their scientific attackers. You can see this in the debate over evolution vs. creationism. Science is vilified and demonized by the creationists, and they as a pack move further away from all things science. Now when scientists warn about global warming, it's no surprise that the creationists are the first to criticize and be skeptical because science has attempted to wrong them in the past - they are now 'at war' with science, which began with evolution but now spills over into all other areas. Wouldn't be surprised if the Texas school board decided to cancel science classes altogether.

Stephen Mackenzie
Stephen Mackenzie

Well, I think we've established the self correcting nature of SCIENCE! A great, thought-provoking post...


Gravity is not the only force to be considered. There are a multitude of forces that are far beyond what our current forms of science are able to quantify. From what I've read, science in it's current state can't actually explain gravity without considering the possibility of dimensions outside of our measure. Including the 7 or so other dimensions that are speculated to exist (M-theory), aside from the 4 we are familiar with (which we still don't even fully understand), that leaves a lot of open ground.

If you consider this to be possibly true, it leaves the method of approach above to be missing components for calculation.

I'm just saying, there is a lot more going on than a lot of scientific thinkers are willing to admit. And, if it exists beyond a scientists perception, does that make it non-science (ha ha)? Isn't that one of the underlying principles of science? To believe in nothing until it can be proven?


So if I'm not completely botching the numbers, the gravity calculator tells me that the black hole at the center of the galaxy exerts slightly more force on me than Pluto does. Funny how astrologers never mention that. And then there's the mass of passing 747s, nearby buildings, one's identical twin (where applicable), etc. And since one's identical twin is also in the middle of being born and is of roughly the same mass, things are likely to get a bit nonlinear, astrologically speaking. And triplets? Well, then it's a three body problem.

OTOH, lunar tides are another matter entirely and can profoundly influence your fortunes, at least if you're a professional surfer. Although I don't think it really counts as astrology at that point.


Alright, pedants, you make good points.

First, I stated in the article that in order to measure the BIGGEST theoretical force, I will consider all planets as if they are aligned directly on one line from the Earth. This I did on purpose, for two main reasons: First, it's going to be a whole lot of mess to calculate the forces from the planets relative to their actual positions, since it would include vectors and directional forces and... well.. this article is meant to deliver the point in relatively simple terms, so I decided to simplify the situation (spherical cows, people! :)

Second, I wanted to make sure that no astrology-proponent can claim that in any theoretical situation this force can be bigger. I chose the BIGGEST POSSIBLE THEORETICAL force. No stronger force is possible, this is it. And yet, it's still minute and incredibly tiny compared to a relatively empty delivery room. That's the point.

Regarding my calculations, and your points about the accuracy:

Something in the process of writing-out the calculation in the post was indeed wrong (for some of the planets): I neglected to convert from km to meters. Shame on me! I am fixing it now.

Surprisingly, I got Saturn right and missed on Jupiter. Not quite sure what made me miss the conversion on one and not the other, or my math-checkers to miss it. Also, in the case of Pluto, the result was correct (1.27*10^(-13)) but when I rewrote it, for some reason beyond my comprehension (it was midterm time.. brainmelt?) I wrote the answer verbally as ^(-8).

When I verified the results, something slightly weird happened: I recalculated the force from all the planets (I even added a conversion in the same line to make it consistent), and I found 3 instances where I was converting wrong (Pluto and Jupiter were two). However, when I continued to recalculate the combined force, it came out the same.

So, either my branmelt was only for the writing-part of the post (hence, my actual calculations were good, but when I wrote them out in the post they were screwey), or I still have said brainmelt. It was very important for me to relate to your comments tonight, but I am not sure I will be doing well trying to figure it out at this late hour. I therefore will ask for your patience as I try to go over it all again and figure out what happened.

If anyone feels generous enough to help out, it would be greatly appreciated, but if not, I will tend to it as soon as possible and verify all my calculations yet again.

In any case, I have added the force-calculator tool to make sure that anyone can calculate any force from any item on his/her own, without trusting my (possibly faulty) math. The calculator works. Try it!

Now, just for the sake of the argument here -- that would result in a smaller force from the planets, and hence will not change the conclusion.

I made this page mainly for people who are not well versed in either math or astronomy and want to see the process of thinking this problem through.

I appreciate the criticism made, and I hope to get more, as I will be fixing all of it.

These claims are often raised by the people who are "on the fence" in astrology; the 'big believers' don't' care about rationality, and the people who know physics, math and astronomy know better. It's the people who don't quite know how to think about this problem that think it's plausible, and this post was for them (that's also why the math can be hidden, so it doesn't 'scare' people away).

So while I really do appreciate the mathematical correction (and I do apologize, and fix now), the criticism about why even bother with the claim I really don't accept. Not everyone is immediately able to analyze this type of claim, and the astrologers take advantage of the lay people to spew nonsense that SOUND plausible. If we don't tackle those subjects -- nonsensical as they may be for us -- then we let them win the crowds.

One more point: I added the force calculator (an online tool, linked above) exactly for the purpose of measuring for yourselves any planet, celestial body or object you want. If you spot more errors or if you want to add more items (like the sun, the moon, the force from a passing car, etc etc) please feel free to do so and add it here in the comments.

I chose to relate strictly to the planets and strictly to a delivery room (no Sun, no Moon, no Earth, etc) because I felt it was the most direct claim I can make without complicating things too much. The tidal force from the moon is a noble claim to pursue, but it's a totally DIFFERENT claim than the one in which the position of the planets affect the newborn baby. The chart made by astrologers to explain the birth includes planets and not the moon. The moon's supposed-effect is seen more in daily horoscopes, and less in the 'newborn/astrology sign' issue. I wanted to stick to one claim at a time.

So, as a summary: I think the best thing that could happen from any post I make is that it starts a debate, and gets people thinking; pointing out errors is one way of getting that, I guess. ;) I really do appreciate the effort and the thought that you all put into this, and I corrected what I could. Please let me know if you find any more errors in the calculations, or if you find any other cool objects that might be relevant to this calculation (the force-calculator can help )

Thanks for taking the time to read and respond!



That's a joke?

If The force from all the planets combined were larger than people, objects and earth gravity the baby were in the space, flying looking for the internatiional space station.

All is about light and the frecuencies that combined express differents levels of concioussnes.

The rational method never could understand it.

Not serious.



Your website is well done and could be very useful. But... please, recheck your calculations.

Even a casual look at "The force from all the planets combined" reveals that there is something fishy here.

I noted that F_saturn>F_jupiter cannot possible be true; later-on I saw that "Pedant" Stephen already rightfully complained about F_pluto>F_neptune ; sigh!

Ralf Muschall
Ralf Muschall

Shouldn't we compare the tidal effect rather than simply the force? The normal gravitational pull is usually offset by inertia and/or local mechanical forces, leaving the tidal effect (AKA Weyl tensor) as the leading nonvanishing term. The strength of this is proportional to the density of the gravitating body and the third power of its angular (i.e. apparent) diameter. With the outer planets as well as doctors and nurses having densities close to that of water, all we need to compare are their angular sizes. E.g. a doctor a few meters away may appear 10 degrees big, Jupiter is around 40 seconds, i.e. approximately 1/1000 of that. Cubing that gives a factor of a billion. Additionally, the effect should be the same if the planet moves by 180 degrees (unless we take into account even higher order terms which are even smaller) - are astrology's predictions invariant w.r.t. such movements?


Quick thing regarding your math: Venus and Mercury are on the other side of the remainder of the planets. As such, their gravity should be subtracted from the other--force has a direction, and theirs is opposite the other planets.

There is a time when it all lines up--when they're all lined up on the opposite side of the sun from Earth. This increases the overall distance between earth and any orbit to the other planet's orbit + 1 AU.

So you need to fix that summation error. Also, in the show math part, you give mercury 1.33*10^-8 N but otherwise list it at 1.21*10^-8 N.

Not a big deal, given the relative orders of magnitude. Just FYI.


Just to play devil's advocate here...

Never mind physics, what about psychology? For instance, what is the effect of the annual timing of birthdays? If your birthday comes in the middle of the summer, would that have a different emotional effect on you than if your birthday came in the middle of the winter? If so (and yes, that's a big if), then this differential stimulus, applied annually, might have a developmental effect on personality.

Or take school-year timing. Will the child be a little old for his/her class, or a little young? This too might have an effect on later personality.

All of the above is speculation. Birthdays are important, especially for impressionable youngsters, but their importance is probably limited. And I suspect that others have tried to study such correlations; so this hypothesis is testable. Have such tests been done?

Stephen Mackenzie
Stephen Mackenzie

Pedant's Corner: Surely Neptune and Pluto can't exert the same amount of force?


Look what you wrote:

"The moon’s gravity is known to affect tides – a powerful force we can witness. Many take this as proof that the planets’ gravity is affecting our bodies. On its face, the claim makes sense."

Indeed. You proceed to show that the gravitational forces from *other* planets are negligible, but you leave out the Moon from those computations. So, I guess we are to be persuaded by your sensible sounding argument above that the Moon's gravity does affect our bodies, but the gravity of the planets further away does not.


You're ignoring the 9 months between conception and birth. What happens to the math if you take that into account?


Nice :)

I didn't even know there are astrologers that claim there is a scientific explanation for astrology. I always thought it has something to do with ancient gods associated with each planet or something like that.

Don't push this too hard or astrologers would just start putting the location of the nurse etc. into their "calculations".


  1. […] quite dead yet, so beating it isn’t such a bad idea. My friend Moriel Schottlender wrote up a nice dissection of astrology walking through the steps showing (despite many astrologers’ claims) that gravity clearly is […]

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