Today I got to pondering about the whole panspermia and Alien visitor theories, and few things struck me that I have so far not heard mentioned reading articles and viewpoints about these subjects. Whether I just haven't heard them and there's logical reasons around them, they've been swept under the carpet, or they simply haven't come up, I don't know, but maybe some of you out there could enlighten me.
Firstly I got to thinking of divers and mountain climbers on our own planet. As most of you would no doubt know, when a diver dives to deep depths, he has to go down slowly, and come back up slowly due to the changes in pressure (atmospheres), or he risks potentially fatal side effects.
Decompression sickness can happen in these situations:See here for a more thorough list of cause and side effects
A diver ascends rapidly from a dive or does not carry out decompression stops after a long or deep dive.
An unpressurized aircraft flies upwards.
The cabin pressurization system of an aircraft fails.
Divers flying in any aircraft shortly after diving. Pressurized aircraft are not risk-free since the cabin pressure is not maintained at sea-level pressure. Commercial aircraft cabin pressure is often maintained to about 8,000 feet above sea level.
A worker comes out of a pressurized caisson or out of a mine, which has been pressurized to keep water out.
An astronaut exits a space vehicle to perform a space-walk or extra-vehicular activity where the pressure in his spacesuit is lower than the pressure in the vehicle.
This surfacing diver must enter a recompression chamber to avoid the bends.These situations cause inert gases, generally nitrogen, which are normally dissolved in body fluids and tissues, to come out of physical solution (i.e., outgas) and form gas bubbles.
Anybody familiar with diving will also know that if you dive to a certain depth with a sturdy container, and capture something like a fish or shrimp, then return to the surface, the pressure inside is still the same as at the depth you took it from. When you open that container quickly , and release the pressure, the fish will explode. The same can happen while fishing if you bring a fish up too quick, their swim bladders will explode.
The similar effects due to lack in air pressure and oxygen concentrations can be deadly to mountain climbers on Everest.
Messner described his time at the top of the world as being like "a single gasping lung floating over the mists and summit".
At this altitude, the air is so thin and there is so little oxygen present that, no matter how many breaths you take, your body is slowly dying.
Starved of O2, your lungs will fill with fluid, your brain will swell and if you don't descend, you will slip into a coma and die. No wonder they call it the "death zone".
Many people who travel from sea level to over 8,000 feet report symptoms ranging from headache to loss of appetite and nausea. Why? As the available oxygen falls, the body responds by increasing the blood flow to the brain, but it can overcompensate, and fluid leaks from the blood vessels into the brain causing it to swell. The result is Acute Mountain Sickness. Cases can run the spectrum from mild to life threateningly severe swelling called High Altitude Cerebral Edema (HACE).
Not surprisingly, the greater the elevation gain, the more severe the swelling. In severe cases the brain can get squeezed down the spinal cord which results in death. The way to avoid falling victim is to ascend gradually, about 1,000'/day over 8,000' which gives your body time to acclimatize properly.
Now all these effects are due to the fact that the human body is specifically adapted to the air pressure within a certain zone, and it doesn't take much change to start feeling the ill-effects if they change too quickly, just like your ears popping when driving over a small mountain etc. This is why spaceships and space suits are pressurized for space travel, with airlocks etc for when an astronaut exits the spacecraft. If his suit was to rupture in space, well I'm sure you know what would happen, pooped eyeballs and collapsed lungs are just a few the effects.
Now air and water pressures are specifically related to the gravitational pull of our
Earth, and the weight of gases and water under that gravitational pull, and the compounds of wich water and our
atmosphere are made from. For example certain gases are heavier than others, so if we had the same gravity but lighter gases in our atmosphere, the pressure would drop, and if we had the same atmosphere, but less gravity, the pressure would also drop. Our air pressure at certain levels is a balance between these two forces. (Now I'm certainly no scientist and 99% of this is from memory only and if any body wants to chime in and correct me, feel free, that's why I'm posting this).
First let's talk about microorganisms frozen on a space rock, assuming they survived the trip off their planet and through space, and onto our planet. The overwhelming chances are that the microorganisms would be adapted to a different gravity, different atmosphere, and would be adapted to completely different atmospheric pressures. Lets say that it survived the impact with earth, still frozen somehow, and then the ice melted away from it (remember that climbers have to acclimatize at the rate of 1000ft per day). Once the ice had melted from off this microorganism, it would begin defrosting, and once it did, wouldn't it slowly implode or explode due to the change in pressure from which it was adapted and frozen. Maybe there are experiments that have been done with microorganisms rapidly subjected to great pressures or negative pressures, I don't know.
Now let's talk about complex life forms with muscular, circulatory, and skeletal systems (since that's the only life we know of that could be Aliens that people describe communicating with, and we're yet to encounter some methanoid cosmic nerve-fart
). Since the alien encounters we all read about describe the shapes of their bodies, heads and eyes etc, we must assume they don't wear pressurized space suits, although I guess it's possible they use some biological or biomechanical outer skin, so what we look at isn't actually their true form (interesting in itself). Also they seem to move around just like humans in our atmosphere(?).
Our skeletal, respiratory, circulatory and muscular systems are specifically adapted to the conditions here on Earth. If our bones weren't strong enough they would snap under our own weight. If our hearts and circulatory systems weren't adapted properly they wouldn't be able to pump the blood from your feet to your brain or would overload your blood pressure. Take the giraffe for example...
A giraffe's heart must be quite large (it is over 24 lbs) to pump blood to the giraffe's head. A series of special one-way valves in the neck regulates blood flow, and there is a special net of elastic blood vessels at the base of the brain. Without these valves and elastic blood vessels, the blood pressure in the giraffe's head would be immense when it bends over, enough to cause brain damage. All of these features -- large heart, valves in the jugular vein, and wondernet of vessels -- must be in place simultaneously or the giraffe would die.
Now if your muscular system wasn't strong enough for our gravity you would fall into a heap on the ground, just as a baby cannot walk until he develops his muscles slowly by kicking, then crawling, the up onto his feet, along with the needed coordination. For an alien to come down to Earth, exit his spaceship, and walk around, his body would have to be developed specifically (or dam well close to) the conditions here on Earth, and what would those odds be, considering the range of atmospheric pressures and gravity on the planets in out solar system, let alone the variances in pressures here on Earth. (As a side topic while it comes to mind, have you ever wondered how it came to be that our moon can PERFECTLY eclipse our sun, being at the exact size and at the correct distance to do this? The odds are over 1 in a trillion, and this setup perfectly regulates our tides! Coincidence? Hardly. Now back to the topic at hand) Chances are more likely that he would bounce around like an astronaut on the moon with an over developed muscular system, or fall flat on his face with an under developed system, never able to climb back to his feet. His bones might even snap like twigs if they were under developed. All this and that's only taking gravity into account. What if the pressures were completely different to what this alien had adapted to on his home planet? Simple, he would either explode, or implode.
Okay, say they are so intelligent that they land and acclimatize slowly via decompression or pressurization, but think how long that it takes us just within our atmosphere alone, and we live and are specifically adapted for life on Earth, and this would only take care of the air pressure problem, not gravity. However I guess they could do this pressurize/depression during travel, if they knew the conditions of the target planet, but how far is it possible to pressurize or depressurize without causing serious damage to themselves? The original conditions would still have to be pretty close to the target conditions, just like a mountain climber, and there is only so far a diver can go without protection from these pressures before he begins to be crushed.
Also they seem to be able to take humans aboard their craft and poke and prod, with both the humans and the Aliens under the same conditions. Unless there is anything I'm missing, there are only two choices.
1. Aliens do not exist.
2. Aliens are not who they say they are.