WHAT IS TARGETED PANSPERMIA? IT'S POSSIBLE? - BIOLOGY - 2025

The directed panspermia refers to a mechanism that explains the origin of life on planet Earth, because of an alleged inoculation of life or fundamental precursors, by an extraterrestrial civilization.

In such a scenario, the extraterrestrial civilization should have considered the conditions of planet Earth as suitable for the development of life and have sent an inoculum that has successfully reached our planet.

Figure 1. Panspermia: a hypothesis the extraterrestrial origin of life on Earth. Source: Silver Spoon Sokpop, from Wikimedia Commons

On the other hand, the hypothesis of panspermia raises the possibility that life was not generated on our planet, but had an extraterrestrial origin, but that it reached Earth accidentally through multiple different possible ways (such as, attached to meteorites that collided with Earth).

In this hypothesis of (undirected) panspermia, it is then considered that the origin of life on Earth was extraterrestrial, but was not due to the intervention of an extraterrestrial civilization (as proposed by the mechanism of directed panspermia).

From a scientific point of view, directed panspermia cannot be considered a hypothesis, as it lacks evidence to support it.

Directed Panspermia: Hypothesis, Conjecture, or Possible Mechanism?

Hypothesis

We know that a scientific hypothesis is a logical proposition about a phenomenon, based on information and data collected. A hypothesis can be confirmed or refuted, through the application of the scientific method.

The hypothesis is formulated with the intention of providing a possibility for the resolution of a problem, on the scientific basis.

Guess

On the other hand, we know that by conjecture it is understood, a judgment or opinion that is formulated from incomplete evidence or data.

Although panspermia could be considered as a hypothesis, since there is some little evidence that could support it as an explanation for the origin of life on our planet, directed panspermia cannot be considered as a hypothesis from the scientific point of view, for the following reasons:

1. It presupposes the existence of an extraterrestrial intelligence that directs or coordinates said phenomenon, assuming that (although it is possible) it has not been scientifically confirmed.
2. Although it could be considered that certain evidences support the panspermic origin of life on our planet, these evidences do not provide any indication that the phenomenon of inoculation of life on Earth has been "directed" by another extraterrestrial civilization.
3. Even considering that directed panspermia is conjecture, we must be aware that it is very weak, being based only on suspicion.

Possible mechanism

It is preferable, from a formal point of view, to think of directed panspermia as a “possible” mechanism, rather than as a hypothesis or conjecture.

Targeted panspermia and its possible scenarios

If we consider directed panspermia as a possible mechanism, we must do so considering the probabilities of its occurrence (since, as we have commented, there is no evidence to support it).

Three possible scenarios

We can evaluate three possible scenarios in which directed panspermia could have occurred on Earth. We will do so, depending on the possible locations or origins of the extraterrestrial civilizations that could have inoculated life on our planet.

It could be possible that the origin of that extraterrestrial civilization has been:

1. A galaxy that does not belong to the close environment of the Milky Way (where our solar system is located).
2. Some galaxy of the "Local Group", as the group of galaxies where ours is, the Milky Way is called. The "Local Group" is made up of three giant spiral galaxies: Andromeda, the Milky Way, the Triangle galaxy, and about 45 smaller ones.
3. A planetary system associated with some very close star.

Figure 2. 3D Map of the Local Group in which the Milky Way is located. Source: Richard Powell, via Wikimedia Commons

In the first and second scenarios described, the distances that the "inocula of life" would have to travel would be enormous (many millions of light years in the first case and in the order of about 2 million light years in the second). Which allows us to conclude that the chances of success would be almost zero, very close to zero.

In the third scenario described, the probabilities would be a little higher, however, they would remain very low, because the distances they should have traveled are still considerable.

In order to understand these distances, we must do some calculations.

A small calculation to be able to size the problem

It should be borne in mind that when you say "near" in the context of the universe, you are referring to enormous distances.

For example, Alpha Centauri C, which is the closest star to our planet, is 4.24 light years away.

For the inoculum of life to have reached Earth from a planet orbiting Alpha Centauri C, it would have to have traveled uninterruptedly, for a little more than four years at a speed of 300,000 km / s (four light years).

Let's see what these figures mean:

• We know that a year has 31,536,000 seconds, and if we travel at the speed of light (300,000 km / s) for a year, we will have traveled a total of 9,460,800,000,000 kilometers.
• Suppose that the inoculum came from Alpha Centauri C, a star that is 4.24 light years from our planet. Therefore, it had to travel 40,151,635,200,000 km from Alpha Centauri C to Earth.
• Now, the time it took for the inoculum to travel that colossal distance must have depended on the speed with which it could have traveled. It is important to note that our fastest space probe (Helios), registered a record speed of 252,792.54 km / h.
• Assuming the trip was made at a speed similar to Helios, it must have taken approximately 18,131.54 years (or 158,832,357.94 hours).
• If we assume that, as a product of an advanced civilization, the probe they sent could have traveled 100 times faster than our Helios probe, then it must have reached Earth in about 181.31 years.

The vastness of the universe and directed panspermia

We can conclude from the simple calculations presented above, that there are regions of the universe so far apart that, although life had arisen early on another planet and an intelligent civilization had considered directed panspermia, the distance that separates us would not have allowed some artifact designed for such purposes would have reached our solar system.

Wormholes

Perhaps it could be assumed that inoculum travel through wormholes or similar structures (seen in science fiction movies) might be possible.

But none of these possibilities has been scientifically verified, since these topological characteristics of a spacetime are hypothetical (so far).

Everything that has not been verified experimentally with the scientific method, remains as speculation. A speculation is an idea that is not well founded, because it does not respond to a real basis.

Figure 3. Hypothetical representation of a “wormhole” showing two possible paths to reach a point in space, a long path (in red) and a shortcut through the hole itself (in green). Source: Panzi [GFDL (http://www.gnu.org/copyleft/fdl.html), via Wikimedia Commons

Directed panspermia and its relationship with other theories

Directed panspermia can be very attractive to a curious and imaginative reader, as well as Lee Smolin's "Fertile Universes" or Max Tegmark's "Multiverse" theories.

All these theories open up very interesting possibilities and pose complex visions of the universe that we can imagine.

However, these "theories" or "proto-theories" have the weakness of lacking evidence and, furthermore, they do not pose predictions that can be experimentally contrasted, fundamental requirements to validate any scientific theory.

Despite what was stated earlier in this article, we must remember that the vast majority of scientific theories are constantly renewed and reformulated.

We can even observe that in the last 100 years, very few theories have been verified.

The evidences that have supported new theories and that have allowed to verify older ones, such as the theory of relativity, have emerged from new novel ways of posing hypotheses and designing experiments.

We must also consider that technological advances provide new ways to test hypotheses that previously could have seemed refutable, due to the lack of adequate technological tools at the time.

References

1. Gros, C. (2016). Developing ecospheres on transiently habitable planets: the genesis project. Astrophysics and Space Science, 361 (10). doi: 10.1007 / s10509-016-2911-0
2. Hoyle, Fred, Sir. Astronomical origins of life: steps towards panspermia. Edited by F. Hoyle and NC Wickramasinghe. ISBN 978-94-010-5862-9. doi: 10.1007 / 978-94-011-4297-7
3. Narlikar, JV, Lloyd, D., Wickramasinghe, NC, Harris, MJ, Turner, MP, Al-Mufti, S.,… Hoyle, F. (2003). Astrophysics and Space Science, 285 (2), 555–562. doi: 10.1023 / a: 1025442021619
4. Smolin, L. (1997). The life of the Cosmos. Oxford University Press. pp. 367
5. Tully, RB, Courtois, H., Hoffman, Y., & Pomarède, D. (2014). The Laniakea supercluster of galaxies. Nature, 513 (7516), 71-73. doi: 10.1038 / nature13674
6. Wilkinson, John (2012), New Eyes on the Sun: A Guide to Satellite Images and Amateur Observation, Astronomers' Universe Series, Springer, p. 37, ISBN 3-642-22838-0