Friday, December 6, 2019
Contact us    |    Advertise    |   Help    |   Cookie Policy    |   Privacy Policy    RSS icon Twitter icon Facebook icon
    Home  ·  News  ·  Forum  ·  Stories  ·  Image Gallery  ·  Columns  ·  Encyclopedia  ·  Videos
Find: in
Unexplained Mysteries is always on the look out for new article writers and contributors. If you've written articles, reviews, news stories or other material that you would like published for free on the site then we want to hear from you - Click here for details.
  Columnist: William B Stoecker

Image credit: NASA/JPL-Caltech

Panspermia revisited


Posted on Wednesday, 27 November, 2019 | 7 comments
Columnist: William B Stoecker


Are we all "aliens"? Did all life on Earth originate elsewhere, with one-celled extremophile bacteria (and perhaps more complex, multi-celled organisms) spreading through space? Or is the situation even stranger and more complex than that, with organisms from other worlds arriving here, and bacteria and other life forms from Earth spreading out to "seed" other planets, moons, and comets? Meteorites that originated on our Moon and on Mars have been found on Earth, usually in Antarctica where they are easily spotted on parts of the ice cap that have not been "contaminated" with rocks formed here. Large asteroid impacts, it seems, can blast surface material from a planet in an upward direction exceeding the planet's escape velocity, and some of that material drifts through space and may fall on another world. Despite the pressures and high temperatures of the impacts (both when the rocks are blasted off their home worlds and when they impact with their new home), researchers believe a few organisms might survive. European researchers used a two stage light gas gun to fire frozen algae pellets into water at almost seven kilometers per second... and, incredibly, some were still alive.

In fact, the idea of life spreading through space, called "panspermia," dates back to ancient times, but the first fully developed theory to explain it was the work of Swedish chemist Svante Arrhenius in 1903. He theorized that microorganisms might be carried to extreme altitudes by violent storms and then be propelled by the pressure of sunlight beyond their home world's escape velocity and eventually drift down through the atmosphere of another world. In modern times the most famous proponents of this theory have been the late British astronomer Fred Hoyle, and his colleague Chandra Wickramasinghe. Bacteria and phytoplankton have been found on the outside of orbiting spacecraft, still viable and able to be revived, whether they originated elsewhere or came from Earth. NASA has done tests as well, proving that many one celled organisms, and not just extremophile bacteria, can survive in the vacuum and radiation in space.

Planets capable of supporting the kind of ecosystem we have on Earth, with photosynthesizing plants producing large amounts of oxygen, and the oxygen being breathed in by animals that feed on the plants (and on one another) may be rare, but there is reason to suspect that bacteria and perhaps more complex organisms may exist in worlds long believed to be lifeless, like the moons of the outer planets in our Solar System, and perhaps in Mars and even in our own Moon. Astronomers speak of the "Goldilocks zone," a region neither too close nor too far from a star, where the stellar light can produce temperatures suitable for our kind of life. But there are also internal Goldilocks zones within planets and moons and dwarf planets. Like our own Earth, the cores of many worlds are very hot, often so hot no life can survive. But at more moderate depths, even on worlds far from the Sun, where surface temperatures are close to absolute zero, moderate temperatures exist. Extremophile bacteria have even been found alive in rocks so deep in Earth's crust that the temperature there is above the sea level boiling point of water. Only the immense pressure at depth keeps water in a liquid state. And of course, bacteria thrive in hot springs here on Earth, and around "black smokers," deep sea vents that emit superheated water.

The exact reason for the internal heat of planets and stars is not fully understood, but hydrogen fusion is believed to power stars, and worlds not massive enough to sustain fusion reactions have heat left over from their initial formation, and from the decay of radioisotopes. In addition, moons orbiting close to planets, especially if their orbits are eccentric, are stressed by tidal forces, generating a great deal of heat. In general, large, massive bodies are hotter than smaller ones; stars are hotter and more massive than planets; massive Jupiter's core is hotter than Earth's; and the Moon's core is cooler than ours. In addition to the known sources of heat, there may be some unknown energy permeating all of space that is absorbed by planets and stars. Jupiter and the other giant planets may have no internal habitable zone, for they have no solid surface, and their turbulent atmospheres would tend to carry any organisms down to regions where even extremophiles could not survive the heat.
But there is strong evidence that smaller objects in our Solar System have internal Goldilocks zones. Jupiter's moon Europa, with a diameter over 3,000 kilometers, is warm enough inside to have cryovolcanos. On cold outer worlds, water ice is a "rock" or mineral, and the "lava" is liquid water. Jupiter's moon Ganymede is the largest in our Solar System, with a 5,268 kilometer diameter, and NASA scientists believe that it has an internal ocean of liquid water. Titan, a moon of Saturn, is almost as large as Ganymede, and is so cold on the surface that there are oceans of liquid methane and ethane, but there is evidence of warmer temperatures and liquid water underground. Saturn's moon Enceladus has cryovolcanos that eject water and water vapor far into space; if there are living organisms in it they could drift to Earth and other worlds or land on comets that might carry them Earthward. Pluto, a dwarf planet far out on the edge of the Kuiper Belt, has a surface temperature only a few degrees above absolute zero, and its crust is composed of ice. But the smooth surface and other features have convinced astronomers that Pluto probably has an ocean of liquid water beneath its frozen surface, which is partly covered with organic compounds. Ceres, a dwarf planet in the main asteroid belt between Mars and Jupiter, has a diameter of only 965 kilometers, but its mostly smooth surface and possible cryovolcanos indicate warmer temperatures and liquid water beneath the crust.

All of space contains organic molecules, as do comets, and we cannot rule out the possibility that organisms live within the comets, thawing and springing to life whenever the comet comes close enough to the Sun to melt the water ice which is known to be present in virtually all of them. If one celled organisms are present, many of them would be ejected into the comet's tail... and the Earth has passed through comet tails many times.

It is even possible that multi-celled plants and animals might originate on other worlds and survive the journey through space to arrive on Earth. Consider the tardigrades, tiny (barely visible to an unaided human eye) eight legged animals with primitive, lens-less eyes that live on damp moss and similar habitats, eating one celled plants and animals and other tardigrades. In tests, they have survived the vacuum, extreme temperatures, and radiation in space, entering a state of suspended animation and reviving if placed in liquid water. Biologists have tentatively classed the tardigrades by placing them in their own phylum, Tardigradia, and assuming that it belongs in the super-phylum Ecdysozoa, which includes Arthropods, and nematode worms among other phyla. But this is pretty much a wild guess. Tardigrades might very well have originated, for all we know, inside Enceladus, been ejected into space, and carried by comets to our vicinity.

Understand that conditions suitable for life do not prove that life exists in these worlds. But our universe, often very hostile to life, with black holes and gamma ray bursts and supernovae, naturally produces organic compounds, composed of some of the most common elements, principally hydrogen, oxygen, carbon, and nitrogen. And beyond Pluto in our Solar System, scientists have already discovered other dwarf planets. Since comets are more common than planets and planets are more common than stars (just as grains of dust outnumber boulders), can we rule out the possibility that interstellar space is filled with all manner of objects, including dwarf planets, worlds the size of Earth, and even Jupiter-sized planets? And if many of these have internal Goldilocks zones, there may be more life in interstellar space than within planetary systems orbiting stars. And that life may spread in all directions, with all the creatures in the universe (including us) being distantly related.

William B Stoecker

Article Copyright© William B Stoecker - reproduced with permission.



 
  Other articles by William B Stoecker

The planets that never were
Columnist: William B Stoecker | Posted on 6-15-2019 | 3 comments
There has long been a theory that at least some UFOs are craft from one or more alien planets. But which planets? Decades ago it was possible to speculate about...


The Time of Moses
Columnist: William B Stoecker | Posted on 7-30-2016 | 4 comments
A good many people used to be fairly familiar with the basic Biblical narrative: A people called the Israelites, more or less the ancestors of modern Jews, were...


Lemuria
Columnist: William B Stoecker | Posted on 6-14-2014 | 2 comments
The legend of Atlantis dates all the way back to Plato, and, according to Plato, the Greeks learned of Atlantis from the Egyptians. By contrast, the legend of a...


Forrestal
Columnist: William B Stoecker | Posted on 5-20-2014 | 4 comments
On 5/22/49 a man jumped, fell, or was thrown or pushed from a small window on the sixteenth floor of Bethesda Naval Hospital in Washington, D.C. A cord from a b...


The Dirty Dozen
Columnist: William B Stoecker | Posted on 4-17-2014 | 6 comments
The term “UFO” means “Unidentified Flying Object.” It does not mean that we are being visited by Sirian Beamships or Pleiadeian Space Brothers. All it means is ...


   View: More articles from this columnist ( 107 total )

 
Last updated forum topics
Forum icon 
Articles by other columnists
Panspermia revisited
Posted 11-27-2019
William B Stoecker on the possibility that life travels between worlds.
 
Witchcraft, UFOs and Rock'n Roll
Posted 11-13-2019
A look back at David Bowie's encounter with witch Walli Elmlark.
 
Nightmares
Posted 11-8-2019
Kathleen Meadows explores the nature and meaning of nightmares.
 
UFO perspectives
Posted 8-19-2019
From the world's top experts (from Maccabee to Friedman).
 
The planets that never were
Posted 6-15-2019
William B Stoecker looks at the habitability of our solar system.
 
Gef the talking mongoose
Posted 3-3-2019
Sean Casteel recounts the very strange case of a rather bizarre creature.
 
The Paranormalist
Posted 1-25-2019
David Lange takes a look at the work of paranormal investigator Christopher Chacon.
 
Tesla's secret space program
Posted 12-11-2018
A look in to the world of Nikola Tesla conspiracy theories.
 
Life lessons and esoteric secrets
Posted 11-14-2018
Kathleen Meadows talks about the many things that the Tarot can reveal.
 
Moscow's mysterious lights
Posted 10-20-2018
Edward Crabtree investigates reports of UFOs over Russia.
 
Halloween - A Scary Season Rooted In Reality
Posted 9-18-2018
Melissa Newman takes a closer look at Halloween.
 
Nikola Tesla - The Unknown 'Healer'
Posted 8-22-2018
Did Tesla's work inspire a new method of healing ?
 
July, Cancer and the Moon Card
Posted 7-27-2018
Kathleen Meadows takes a look at this month's Tarot card readings.
 
UFOs: Are they friend or foe ?
Posted 6-19-2018
Sean Casteel investigates reports of hostile alien visitors.
 

 View: View more column articles
 
Top   |  Home   |   Forum   |   News   |   Image Gallery   |  Columns   |   Encyclopedia   |   Videos   |   Polls
UM-X 10.712 Unexplained-Mysteries.com (c) 2001-2019
Terms   |   Privacy Policy   |   Cookies   |   Advertise   |   Contact   |   Help/FAQ