As a science fiction author, I deliberate on matters dealing with getting heroes and villains chasing one another through the universe. The scale of such distances is so vast that authors just side-step the issue and readers just go with it.
However, I’ve often speculated that the stars are much closer than we think.
The vast bulk of our present day knowledge has come about in the last split-second our existence. Scientific history has been fraught with upheavals and revolutions. We will, without doubt, learn things in the next few decades that can only be imagined today.
The true nature of the universe is still a mystery, and we have largely only theories to explain things. For example, the last documented supernova was in 1604 by Kepler by the naked eye, before the telescope. Since then, we have only theories to explain the idea of supernovas and what role they play in the birth or death of stars. We have yet to observe an actual black hole, anti-matter, or the formation of a new star.
Huge leaps have come from, not hypotheses, but by actually going and seeing.
Between the Hubble Telescope and our own travels in space we have learned that space is not a vacuum, as was once believed, but filled with gases, dust, rocks, asteroids, and more — components that make up stars and planets. The USGS estimates that 2,000,000 pounds of space dust falls to earth every year.
Our position within the Milky Way is surrounded by the very thing that may be clouding our estimates of how far other heavenly bodies actually are from us.
An “Interstellar Fog” deceives us into thinking other stars are unreachable.
Homo Erectus pondered the skies a long as 3 million years ago. Nicolaus Copernicus formulated the heliocentric model (1543). Until then, people believed that Earth was fixed and that the sun and stars revolved around us. Here’s an astronomical timeline.
Even when we breached Earth’s atmosphere, outer space appeared to be a vacuum by way of comparison to our dense atmosphere.
Simple observation proves to ordinary people that light is affected by the “unseen”.
Look at a shadow of a hot cup of coffee in the morning sunshine. The waves of heat cast shadows.
Look across an empty parking lot on a hot day. Waves of heat distort our view of things on the other side.
You may have observed looking across a vast plane or desert and seen what looks like bodies of water. This mirage is the bending of light and reflecting things above the horizon, like the sky.
There is a difference between “actual sunrise” and “perceived sunrise”, when the atmosphere bends light, much like a magnifying glass, and makes the sun to appear to rise before the direct path of the rays reach us (by as much as twelve minutes).
Air is invisible, right? May be between your eyes and your hand, but across greater distances, light is distorted and diffused by air, particulate matter, and water vapor.
At sea-level, a night sky can appear hazy due to atmospheric pressure and humidity. Go up a mountain, where many astronomical observatories are built, and your view is much better because of less air between the observer and the outer atmosphere.
Think of how much light is blocked by water vapor beneath thunderclouds.
Imagine you’re driving on a foggy night. Street lights and oncoming traffic appear very distant or as a faint glow until you’re very close.
Imagine observing a city across a bay that is blanketed by light fog. You can see the lights, but they appear very distant and murky.
What if we drive around the bay and get closer to the city. We’re still in a fog, but we can better judge distance the less “atmosphere” there is between us and the city’s lights.
The same is likely true of behavior of light across the vast distance of space. Light is diffused, bent, and blocked by “fog materials”.
Take a look at pictures of your favorite nebulas.
In addition, light can be comparatively diminished by the infinite light sources. Imagine you’re in a dark sports stadium, and your friend on the other side shines a flashlight. You spot him right away, and the flashlight seems modestly bright. Now, turn on the stadium lights and the flashlight all but disappears. Yet, it’s still putting out just as much light as before.
If we were outside the “interstellar fog” of the gases, dust, rocks, etc., we might see that other stars are not nearly as far as we suspected. But, we’re in the midst of such a fog, and our observations from our singular perspective in the universe will remain the same until we “go and see”.
We’ve learned volumes about our galactic neighbors by sending probes, and rovers to Mars, and men to the moon. Until we “go and see” we have largely speculation about what’s beyond our own galaxy. Sure, present day technology has some very sophisticated equipment, but speaking in absolutes about the universe from our (relatively) fixed position is like taking a picture of grains of sand and interpreting all of Earth.
One of the methods of calculating the distance to stars is by observing a star in January, then the same one in July when Earth is on the opposite side of its orbit around the sun. The (miniscule) differences in angles via parallax effects are crunched through formulae, and voila, X number of light years.
Let’s go back to the bay as we’re looking across to the city. We observe one particular light, then move a millimeter to the left, then measure the difference in angles.
The ratio of Earth’s two positions (186 millioin miles apart) to the nearest star (Alpha Centuri at 25 trillion miles away) gives a ratio of 1: 0.0000074. I suspect there’s room for error.
Again, we have not witnessed a supernova in over 400 years. We’ve got equipment that can see into space better, but we’re not seeing things happening real-time. The only way we’ll know for sure is to “go and see”.
Please share your ideas about the idea of interstellar fog and its effect on our observation of the universe.
Calla Cofield of Space.com writes about “dark matter” and light halos. Ya’ think it’s all linked together?