Biometric analysis of plants

Mar 11, 2022
Hello, what programs can be used for biometric analysis of plants? I only know "STATISTICA". Are there simple and convenient to use?
May 8, 2022
Hello, what programs can be used for biometric analysis of plants? I only know "STATISTICA". Are there simple and convenient to use?
I am not sure if this may be of help, but interestingly there seems to be very little information in the field of plant biometrics. Weird!

Plant species biometric using feature hierarchies (2008)
Biometric identification is a pattern recognition based classification system that recognizes an individual by determining its authenticity using a specific physiological or behavioural characteristic (biometric).
In contrast to number of commercially available biometric systems for human recognition in the market today, there is no such a biometric system for plant recognition, even though they have many characteristics that are uniquely identifiable at a species level.
The goal of the study was to develop a plant species biometric using both global and local features of leaf images. In recent years, various approaches have been proposed for characterizing leaf images. Most of them were based on a global representation of leaf peripheral with Fourier descriptors, polygonal approximations and centroid-contour distance curve.
May 8, 2022
One biometric that is common to all Eukaryotic life is the presence of microtubules in the cytoskeleton and cytoplasm in every cell of every living organism. Trillions of nanoscale dipolar coils that act as electrochemical potentiometers.
In plants they may be instrumental in photosynthesis.

It is "the little engine that could". Thread to follow as soon as I have a good generalized introductory opening post.
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The cytoskeleton is a cellular "scaffolding" or "skeleton" that crisscrosses the cytoplasm. All eukaryotic cells have a cytoskeleton, and recent research has shown that prokaryotic cells also have a cytoskeleton. The eukaryotic cytoskeleton is made up of a network of long, thin protein fibers and has many functions. It helps to maintain cell shape. It holds organelles in place, and for some cells, it enables cell movement. The cytoskeleton also plays important roles in both the intracellular movement of substances and in cell division. Certain proteins act like a path that vesicles and organelles move along within the cell. The threadlike proteins that make up the cytoskeleton continually rebuild to adapt to the cell's constantly changing needs. Three main kinds of cytoskeleton fibers are microtubules, intermediate filaments, and microfilaments.

  • Microtubules, shown in Figure below (a), are hollow cylinders and are the thickest of the cytoskeleton structures. They are most commonly made of filaments which are polymers of alpha and beta tubulin, and radiate outwards from an area near the nucleus called the centrosome. Tubulin is the protein that forms microtubules. Two forms of tubulin, alpha and beta, form dimers (pairs) which come together to form the hollow cylinders. The cylinders are twisted around each other to form the microtubules. Microtubules help the cell keep its shape. They hold organelles in place and allow them to move around the cell, and they form the mitotic spindle during cell division. Microtubules also make up parts of cilia and flagella, the organelles that help a cell move.
  • Microfilaments, shown in Figure below (b), are made of two thin actin chains that are twisted around one another. Microfilaments are mostly concentrated just beneath the cell membrane, where they support the cell and help the cell keep its shape. Microfilaments form cytoplasmatic extensions, such as pseudopodia and microvilli, which allow certain cells to move. The actin of the microfilaments interacts with the protein myosin to cause contraction in muscle cells. Microfilaments are found in almost every cell, and are numerous in muscle cells and in cells that move by changing shape, such as phagocytes (white blood cells that search the body for bacteria andother invaders).
  • Intermediate filaments differ in make-up from one cell type to another. Intermediate filaments organize the inside structure of the cell by holding organelles and providing strength. They are also structural components of the nuclear envelope. Intermediate filaments made of the protein keratin are found in skin, hair, and nails cells.
Screenshot 2023-02-16 at 16.31.05.png
(a) The eukaryotic cytoskeleton. Microfilaments are shown in red, microtubules in green, and the nuclei are in blue. By linking regions of the cell together, the cytoskeleton helps support the shape of the cell. (b) Microscopy of microfilaments (actin filaments), shown in green, inside cells. The nucleus is shown in blue.

Screenshot 2023-02-16 at 16.37.05.png

  • The cytoplasm consists of everything inside the plasma membrane of the cell.
  • The cytoskeleton is a cellular "skeleton" that crisscrosses the cytoplasm. Three main cytoskeleton fibers are microtubules, intermediate filaments, and microfilaments.
  • Microtubules are the thickest of the cytoskeleton structures and are most commonly made of filaments which are polymers of alpha and beta tubulin.
  • Microfilament are the thinnest of the cytoskeleton structures and are made of two thin actin chains that are twisted around one another.


Microtubules are microscopic hollow tubes made of the proteins alpha and beta tubulin and they are part of a cell’s cytoskeleton, a network of protein filaments that extends throughout the cell, gives the cell shape, and keeps its organelles in place. Microtubules are the largest structures in the cytoskeleton at about 24 nanometers thick. They have roles in cell movement, cell division, and transporting materials within the cells.

Microtubules are hollow cylinders made up of repeating protein structures, specifically dimers* of alpha and beta tubulin (also referred to in writing as ɑ-tubulin and β-tubulin). Dimers are complexes of two proteins. ɑ-tubulin and β-tubulin bind to each other to form a dimer, and then multiple units of these dimers bind together, always alternating alpha and beta, to form a chain called a protofilament. Then, thirteen protofilaments arrange into a cylindrical pattern to form a microtubule. Microtubules are constantly assembling and disassembling via the addition and removal of dimers. They are said to be in a state of dynamic equilibrium because their structure is maintained even though the individual molecules themselves are constantly changing.

Microtubules are polar molecules, with a positively charged end that grows relatively fast and a negatively charged end that grows relatively slow. Protofilaments arrange themselves parallel to each other in a microtubule, so the positive end of the microtubule always has beta subunits exposed, while the negative end has alpha subunits exposed. Having polarity allows the microtubule to assemble in a specific way and function correctly.

In animal cells, microtubules radiate outwards from an organelle in the center of the cell called a centrosome, which is a microtubule organizing center (MTOC). The cells of plants and fungi do not have centrosomes, and instead the nuclear envelope—the membrane surrounding the cell’s nucleus—is an MTOC.

* The key difference between homodimer and heterodimer is that homodimer is a protein made from two identical proteins, while heterodimer is a protein made from two different proteins.

Protein is a biomolecule composed of amino acid chains. A protein dimer is a quaternary protein structure formed from the union of two protein monomers or two amino acid chains. Generally, they bind with each other by non-covalent bonds. Protein dimers are either homodimers or heterodimers. A homodimer has two identical proteins which are non-covalently bound. Heterodimer has two different proteins bound together. This protein dimer interaction is important in regulation and catalysis.

May 8, 2022
In animal cells, microtubules radiate outwards from an organelle in the center of the cell called a centrosome, which is a microtubule organizing center (MTOC). The cells of plants and fungi do not have centrosomes, and instead the nuclear envelope—the membrane surrounding the cell’s nucleus—is an MTOC.
It appears that it makes no difference how microtubules are arranged for greatest efficiency.

The intra-cellular communication in plants is as effective as the intra-cellular communication in animals.

Plants may not have conscious awareness, but their cellular homeostatic functions are obvious by their growth patterns above ground, toward light, and growth pattern below ground toward the source of gravity . Seeds especially orient their root growth downward.

some plant cells have statoliths, organelles having particles that settle with gravity stimulating gravitropism where root cells grow in the direction of gravity. Shoot cells are stimulated to grow away from gravity.

A role of microtubules in the polarity of statocytes from roots of Lepidium sativum L.
It is proposed that, particularly at the distal statocyte pole, microtubules in coordination with cross-bridging structures, act in stabilizing the polar arrangement of the distal endoplasmic reticulum and, in turn, facilitate an integrated function of amyloplasts, endoplasmic reticulum and plasma membrane in graviperception.
This very interesting conversation reveals how intelligent plants really are, considering that they lack neurons or a brain. Sentience already begins at plant level in .

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write4u -

Plants are incredible engines, who turn CO2 into water and oxygen, and over hundreds of millions of years, they have created an oxygen rich atmosphere conducive for intelligent life.

Plants and animals are both living things, but at first glance, they seem very different. Animals tend to move around, while plants stay rooted in one place. Animals eat their food, while plants convert sunlight into the energy they need. Despite these differences, scientists argue that plants and animals are more similar than they are different. Some living things even blur the line between the plant and animal kingdoms.

Both plant and animal cells carry DNA – genetic material that is passed down from one generation to another. Because of DNA, plants and animals can pass on their genes over time and adapt to the environment around them via natural selection. Plant and animal cells both divide. Cell division is how individual animals and plants grow and replace parts of themselves. Human children reach adult height because of cell division, and grass grows for the same reason. Both plant and animal cells absorb nutrients and convert those nutrients into usable energy. Animal cells absorb nutrients from food, while plant cells absorb energy from sunlight via a process called photosynthesis.

What is absolutely incredible for me is that plants and animals, all known life on earth, appear to share a common ancestor. There are three (known) domains of life on this planet: eubacteria, archae(bacteria) and eukaryotes. The latter are again divided into three kingdoms: plants, animals and fungi. So the last common ancestor between animals and plants was some archaic eukaryote, presumably single-celled, probably 3 (give or take) or 3.5 billion years ago.
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May 8, 2022
What is absolutely incredible for me is that plants and animals, all known life on earth, appear to share a common ancestor. There are three (known) domains of life on this planet: eubacteria, archae(bacteria) and eukaryotes. The latter are again divided into three kingdoms: plants, animals and fungi. So the last common ancestor between animals and plants was some archaic eukaryote, presumably single-celled, probably 3 (give or take) or 3.5 billion years ago.
I am not all that convinced about a single origin of living things, I am sure there is a first origin, but there is no suggestion that there must have been only a single exclusive site of origin when there were many very similar sites on earth at that time.

It all started with the bonding of 2 "common chemicals" with the potential to bond with other "common chemicals" in no particular order.
Natural selection will do the rest.

Robert Hazen proposes that life may well be found elsewhere in the universe, because the raw materials of life on earth are not unique to earth at all. On the contrary, the chemicals of life can be found throughout the universe, even in deep space where radiation creates bio-chemicals in interstellar clouds

There were more than sufficient raw materials available in many locations, each location having a "probabilistic equation" that only requires time and a dynamic environment to eventually stumble on the right pattern as is obvious by the extraordinary variety of species and varieties within species.

That is all it is, a specific pattern that can be formed from existing resources in many places inside the universe.
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The story of Earth is a 4.5-billion-year saga of dramatic transformations, driven by physical, chemical, and—based on a fascinating growing body of evidence—biological processes. The co-evolution of life and rocks unfolds in an irreversible sequence of evolutionary stages. Each stage re-sculpted our planet’s surface, while introducing new planetary processes and phenomena. This grand and intertwined tale of Earth’s living and non-living spheres is coming into ever-sharper focus. Sequential changes of terrestrial planets and moons are best preserved in their rich mineral record. “Mineral evolution,” the study of our planet’s diversifying near-surface environment, began with a score of different mineral species that formed in the cooling envelopes of exploding stars. Dust and gas from those stars clumped together to form our stellar nebula, the nebula formed the Sun and countless planetesimals, and alteration of planetesimals by water and heat resulted in the 300 minerals found today in meteorites that fall to Earth. Earth’s evolution progressed by a sequence of chemical and physical processes, which ultimately led to the origin-of-life. Once life emerged, mineralogy and biology co-evolved, as changes in the chemistry of oceans, the atmosphere, and the crust dramatically increased Earth’s mineral diversity to the more than 5700 species known today.

Robert M. Hazen, Senior Scientist at the Carnegie Institution for Science and Robinson Professor of Earth Science, Emeritus, at George Mason University, received degrees in geology from MIT and Harvard. Author of more than 450 articles and 25 books on science, history, and music.


Once upon a time there were no minerals anywhere in the cosmos. No solids of any kind could have formed, much less survived, in the superheated maelstrom following the big bang. It took half a million years before the first atoms—hydrogen, helium and a bit of lithium—emerged from the cauldron of creation. Millions more years passed while gravity coaxed these primordial gases into the first nebulas and then collapsed the nebulas into the first hot, dense, incandescent stars.

Only then, when some giant stars exploded to become the first supernovas, were all the other chemical elements synthesized and blasted into space. Only then, in the expanding, cooling gaseous stellar envelopes, could the first solid pieces of minerals have formed. But even then, most of the elements and their compounds were too rare and dispersed, or too volatile, to exist as anything but sporadic atoms and molecules among the newly minted gas and dust. By not forming crystals, with distinct chemical compositions and atoms organized in an orderly array of repeating units, such disordered material fails to qualify as minerals.

Microscopic crystals of diamond and graphite, both pure forms of the abundant element carbon, were likely the first minerals. They were soon joined by a dozen or so other hardy microcrystals, including moissanite (silicon carbide), osbornite (titanium nitride), and some oxides and silicates. For perhaps tens of millions of years, these earliest few species—“ur-minerals”—were the only crystals in the universe.

Earth today, in contrast, boasts more than 4,400 known mineral species, with many more yet to be discovered. What caused that remarkable diversification, from a mere dozen to thousands of crystalline forms? Seven colleagues and I recently presented a new framework of “mineral evolution” for answering that question. Mineral evolution differs from the more traditional, centuries-old approach to mineralogy, which treats minerals as valued objects with distinctive chemical and physical properties, but curiously unrelated to time—the critical fourth dimension of geology. Instead our approach uses Earth’s history as a frame for understanding minerals and the processes that created them.

The story of mineral evolution began with the emergence of rocky planets, because planets are the engines of mineral formation. We saw that over the past four and a half billion years Earth has passed through a series of stages, with novel phenomena emerging at each stage to dramatically alter and enrich the mineralogy of our planet’s surface.

Some details of this story are matters of intense debate and will doubtless change with future discoveries, but the overall sweep of mineral evolution is well-established science.


Of the more than 5,000 minerals recognized by geologists, fewer than 100 are thought to constitute 99 percent of the Earth’s crust. Much more than that—over half of all known minerals, in fact—are considered rare, meaning they appear in five or fewer locations on Earth.

And then there are the rarest of the rare: the minerals that have a total known volume of less than one cubic centimeter, or smaller than the size of a sugar cube. Those are the ones that Robert Hazen, a researcher at the Carnegie Institution, and Jesse Ausubel, an environmental scientist at Rockefeller University, like to study.

In the journal American Minerologist, Hazen and Ausubel outlined a new mineral-classification system to help geologists better understand the designation of “rare.” They based their work on a similar system by the biologist Deborah Rabinowitz, who studied rare biological species. According to Rabinowitz, a species can be considered rare if it meets at least one of three criteria: a small geographic range, highly specific habitat requirements, or a small population size.


The Earth is continually evolving. From first atom to molecule, mineral to magma, granite crust to single cell to verdant living landscape, ours is a planet constantly in flux. In this new approach to Earth's own biography, senior Carnegie Institution researcher and national bestselling author Robert M. Hazen reveals how the co-evolution of the geosphere and biosphere--of rocks and living matter--has shaped our planet into the only one of its kind in the Solar System, if not the entire cosmos. Hazen explains how changes on an atomic level translate into dramatic shifts in Earth's makeup over its four and a half billion year existence. Hazen calls upon a flurry of recent discoveries to portray our planet's many iterations in vivid detail--from its fast-rotating infancy when the Sun rose every five hours and the Moon filled 250 times more sky than it does now, to the time before the first continents arose; to the globe-altering volcanism that may have been the true killer of the dinosaurs and certainly ended Permian life.
May 8, 2022
After reading and listening to Dr Hazen, I got the impression that life on earth does not require exotic minerals but utilizes some few hundred chemicals derived from some 6 fundamental elements are common for earthlike planets.

What are the Ingredients of Life?
By Natalie Wolchover
published February 02, 2011
From the mightiest blue whale to the most miniscule paramecium, life as we know it takes dramatically different forms. Nonetheless, all organisms are built from the same six essential elemental ingredients: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur (CHNOPS).
Why those elements? To find out, Life's Little Mysteries consulted Matthew Pasek, a biogeochemist at the University of South Florida.
This demonstrates how easy it is to form several thousand molecules and polymers on earth today , let alone on a planet in environmental turmoil.
Urey/Miller experiment produced all these molecules

In fact Hazen does address this notion that life is a single unique event but is really a 50/50 probabilistic event that may have occurred at different times and different places depending on the environmental dynamics. After all we are talking about some 13 billion years in toto.

(Hazen: 17:50 "you take this and other energetic environments and these molecules can form in many different places") !

Question: If life on earth does not utilize truly rare and exotic chemicals , what would prevent life from originating in several locations on earth or on other ordinary earthlike planets in the universe?

This is why I like to propose that instead of the universe being attuned for life,, life is really attuned to the universe, by using what elements were available.

Would it not be basically a matter of time?
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Rare Earth hypothesis: Why we might really be alone in the universe

The originators of the theory, Peter Ward and Donald Brownlee, explain to Astronomy why they think the development of complex life on other worlds is likely extraordinarily rare.

By Doug Adler | Friday, July 29, 2022

The first spacecraft to explore the space beyond Earth orbit was Pioneer 4 in 1959. Twenty-five years later, in 1984, astronomers Carl Sagan and Jill Tarter founded the Search for Extraterrestrial Intelligence (SETI), a program that has been scouring the cosmos for signs of alien life ever since.

But, to date, neither an international armada of robotic spacefarers nor alien-seeking scientists have found any evidence of extraterrestrial life. Indeed, while our exploration of the solar system has been nothing short of staggering in terms of the images and scientific data obtained, the worlds we’ve visited beyond Earth all appear to be completely sterile.

Even the most dedicated SETI researcher would have to admit that, at least so far, our efforts to find life elsewhere in the universe have been met with an uncomfortable stony silence. But why?

In 2000, two researchers, Peter Ward and Donald Brownlee, published a book that offered a possible explanation for our species’ apparent aloneness. It is called Rare Earth: Why Complex Life is Uncommon in the Universe (Copernicus Books, 2000). Ward, a paleontologist by training, and Brownlee, an astronomer, combined forces to produce what has come to be termed the Rare Earth hypothesis.

Simply stated, the Rare Earth hypothesis suggests that the very unique conditions of Earth that allowed complex life to arise and flourish are exceptionally uncommon — and they’re unlikely to widely occur throughout the universe.

Ward and Brownlee postulated that many fortuitous features of Earth, our Sun, and the solar system led to our highly favorable and surprisingly stable ecosystem. While some of these properties had been widely discussed in astronomy circles before, others had scarcely been mentioned.

According to the Rare Earth hypothesis, without massive gas giants like Jupiter and Saturn, Earth and the rest of the inner solar system would be unceasingly bombarded by potentially devastating debris. (Illustration not to distance scale.)


  • A planet that exists in a favorable part of the right kind of galaxy, where significant amounts of heavy elements are available and sterilizing radiation sources are located far away.
  • An orbit around a star that has a long lifetime (billions of years) but does not give off too much ultraviolet radiation.
  • An orbital distance that allows liquid water to exist at or near the planet’s surface.
  • An orbital distance that is far enough away to prevent the planet from becoming tidally locked to its host star.
  • An orbit that is stable around its host star over cosmic timescales.
  • A planetary tilt that allows for seasonal atmospheric changes to be mild, not severe.
  • A solar system that includes gas giants capable of preventing debris from polluting the inner solar system, reducing the odds of major cosmic impacts and subsequent mass extinctions.
  • A planetary mass large enough to both retain an atmosphere and allow for liquid oceans.
  • A moon large enough to help stabilize the tilt of the planet’s axis.
  • A molten planetary core that generates a significant global magnetic field, largely protecting the surface from solar radiation.
  • The presence of oxygen, and the right amount of oxygen, at the right time for complex life to utilize it.
  • The presence of plate tectonics, which build up land masses, create diverse ecosystems, cycle carbon into and out of the atmosphere, prevent a runaway greenhouse effect, and help stabilize the surface temperature worldwide.
Could we really be alone?
In the two decades since this book was published, interest in these ideas has only grown. Last year, Astronomycaught up with both Ward and Brownlee to discuss the Rare Earth hypothesis. During those conversations, Ward recounted how the whole concept of the Rare Earth hypothesis spawned from a movie-based chat with Brownlee.

“We were just talking about how ridiculous the Star Wars bar room scene was,” said Ward. “That's how it all started. Look at all those aliens! You know, I just think [the notion of aliens everywhere] has been foisted on the public.”

Ward and Brownlee challenged many widely held notions that supported the idea that complex life is out there waiting to be found. For example, while astronomer Carl Sagan often opined that our Sun is an unremarkable star, in reality, about 80 to 95 percent of stars are significantly different from our own in terms of size, mass, luminosity, lifespan, and many other factors.

Furthermore, prior researchers who had attempted to answer the question of why life on Earth was so plentiful yet so rare in the universe had not included plate tectonics in their thinking at all. Indeed, an entire chapter in Rare Earthis devoted to the topic, going to great lengths to explain the role of plate tectonics in shaping Earth into a good place for life. Earth is, to the best of our knowledge, the only body in the solar system with active plate tectonics. And there are many other features of our life-friendly planet that we haven't seen replicated anywhere else in the universe, too.

The Moon's elusive far side comes into focus in this image captured by the DISCOVR spacecraft. Earth's large natural satellite not only produces ocean tides, but also helps stabilize Earth's tilt.

Does simple life count?
It’s important to remember that the Rare Earth hypothesis only applies to the emergence of complex life. Ward and Brownlee believe that simple life, such as bacteria, is widespread in the universe — after all, even the harshest habitats on Earth harbor microbes. However, the pair feel that complex life, metazoans like animals and us, are exceptionally rare.

“If you find life elsewhere, it's likely to be microbial,” said Brownlee. “You know, Earth will have a lifetime of about 12 billion years, but [compared to bacteria], metazoans have a much more restricted range of environmental criteria that they can survive in.” That means that a planet’s environment is conducive to simple life for much longer than it is conducive to complex life.

“The period of time when we have oxygen in the atmosphere — carbon dioxide to go to plants and oxygen for metazoans — is probably only like 10 or 20 percent of [Earth’s lifespan]. So, if you just landed on our planet randomly throughout its entire history, you would not have anything to see.”

Counter-evidence welcome
Just because Ward and Brownlee don’t believe complex life is common throughout the universe, that doesn’t mean they don’t want it found. The duo welcome new data from cutting-edge observatories, like the James Webb Space Telescope (JWST), which seek to reveal the atmospheres of exoplanets in detail. And there are certain atmospheric signatures that would be more revealing than others.

“I think is way more important to try to look for oxygen atmospheres, but also look for reflections that indicate chlorophyll. You're only going to have a number of ways to build specific molecules,” said Ward. “It really does come back to the fact that, as [University of Washington planetary scientist] David Catling has said, any animal equivalent is going to have to need oxygen — a lot of it. You cannot have really rapidly moving creatures and rapidly thinking creatures, which is a form of movement, and not have oxygen in the atmosphere to do it. You're not going to have people living on carbon dioxide out there,” he added.

While compelling, the Rare Earth hypothesis still has its detractors; many of the environmental factors Ward and Brownlee identified in their book have come under fire over the past 20 years. Among the most frequently attacked proposed conditions for complex life is that a large planet like Jupiter is required to keep the inner solar system relatively free of dangerous debris. Some researchers argue such planets could actually increase the frequency of planetary impacts. Other critics have taken issues with the proposed requirements of a global magnetic field and plate tectonics.

With regard to these criticisms, Ward is understanding, encouraging challenges to his ideas. “Good science does a couple of things," he says,"but the most important thing it does is it stimulates other science; good science makes people angry. It makes some people angry enough that they go out and do something about it.”

The Rare Earth hypothesis remains unproven, but it is hard to ignore the plethora of data that Ward and Brownlee have compiled to support their case. The barren and stark surfaces of Mercury, Venus, and Mars all serve as nearby reminders of what a lucky paradise Earth is by comparison. And rare or not, it's the only home we have.

Doug Adler is the co-host of The Right Stuff Companion podcast


The odds seem a bit better for alien life now that we’ve confirmed more than 4,000 exoplanets in our galaxy, about a fifth of them in Earth’s size-range. We know the building blocks of life are present throughout the solar system and the cosmos, and that includes water. We don’t know how readily life begins, whether it’s common or rare, how long it endures. Up the ante to intelligent life, and the questions only multiply. But if life is abundant with its building blocks strewn across the universe, where is everybody? Despite the numbers of Earth like exo-planets coming in, the radio spectrum has so far remained devoid of intelligent signals. We'll remain alone in the cosmos until...we aren't.
May 8, 2022
Indeed, while our exploration of the solar system has been nothing short of staggering in terms of the images and scientific data obtained, the worlds we’ve visited beyond Earth all appear to be completely sterile.
How many earthlike planets are there in our solar system?
Looking at your own backyard doesn't tell you much about the rest of the Universe.
May 8, 2022
The originators of the theory, Peter Ward and Donald Brownlee, explain to Astronomy why they think the development of complex life on other worlds is likely extraordinarily rare.
If it takes such rare complexity why do we have life on earth in the most inhospitable regions and local environments?

To me it proves that life can originate and indeed thrive in a myriad of environments.

I am afraid that all these people always look at "irreducible complexity", rather than a step-by-step self-organization of parts that withstand the test of natural selection under all circumstances and bestow new and more resilient adaptive properties to the self-organizing complexity.

That is the mathematical beauty of Natural Selection over time and spaces.

Since its formation, Earth itself has performed some:
2 billion, quadrilion, quadrillion, quadrillion chemical experiments,
a true astronomical number.
As humanity casts an ever-wider net across the cosmos, capturing evidence of thousands of worlds, an ancient question haunts us: Is anybody out there?

The good news: We know vastly more than any previous generation. Our galaxy is crowded with exoplanets – planets around other stars. A healthy percentage of them are small, rocky worlds, of a similar size and likely similar composition to our home planet.

The ingredients in the recipe for earthly life – water, elements associated with life, available sources of energy – appearto be almost everywhere we’ve looked.

Now the bad news. We have yet to find another “Earth” with life, intelligent or not. Observing signs of possible microbial life in exoplanet atmospheres is currently just out of reach. No convincing evidence of advanced technology – artificial signals by radio or other means, or the telltale sign of, say, massive extraterrestrial engineering projects – has yet crossed our formidable arrays of telescopes in space or on the ground.

And finding non-intelligent life is far more likely; Earth existed for most of its history, 4.25 billion years, without a whisper of technological life, and human civilization is a very late-breaking development.

Is there life beyond Earth? So far, the silence is deafening.

“I hope it’s there,” said Shawn Domagal-Goldman, a research astronomer at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “I want it to be there. I’ll be planning a party if we find it.”

Domagal-Goldman co-leads a team of exoplanet hunters who, in the years and decades ahead, are planning to do just that. Working with scientists across NASA, as well as academic and international partners, his team and others are helping to design and build the next generation of instruments to sift through light from other worlds, and other suns. The goal: unambiguous evidence of another living, breathing world.

While the chances of finding life elsewhere remain unknown, the odds can be said to be improving. A well-known list of the data needed to determine the likely abundance of life-bearing worlds, though highly conjectural, is known as the “Drake equation*.”

Put forward in 1961 by astronomer Frank Drake, the list remains mostly blank. It begins with the rate of star formation in the galaxy and the fraction of stars that have planets, leading step-by-step through the portion of planets that support life and – most speculatively – to the existence and durability of detectable, technological civilizations.

When Drake introduced this roadmap to life beyond Earth, all the terms – the signposts along the way – were blank.

Some of the first few items are now known, including the potential presence of habitable worlds, said researcher Ravi Kopparapu from Goddard, also a co-leader of Domagal-Goldman’s team. He studies the habitability and potential for life on exoplanets.

If we develop and launch a powerful enough space telescope, “we could figure out if we have advanced life or biological life,” he said.


* Drake equation, also called Green Bank equation, is an equation that purports to yield the number N of technically advanced civilizations in the Milky Way Galaxy as a function of other astronomical, biological, and psychological factors. Formulated in large part by the U.S. astrophysicist Frank Drake, it was first discussed in 1961 at a conference on the “search for extraterrestrial intelligence” (SETI), held at the National Radio Astronomy Observatory in Green Bank, W.Va. The equation statesN = R*fpneflfifcL.

The factor R* is the mean rate of star formation in the Galaxy; fp the fraction of stars with planetary systems; ne the number of planets in such systems that are ecologically suitable for the origin of life; fl the fraction of such planets on which life in fact develops; fi the fraction of such planets on which life evolves to an intelligent form; fc the fraction of such worlds in which the intelligent life form invents high technology capable at least of interstellar radio communication; and L, the average lifetime of such advanced civilizations.

These numbers are poorly known, and the uncertainty increases progressively with each factor on the right-hand side of the equation. Widely quoted but at best vaguely known values for these factors are: R* = 10/yr, fp = 0.5, ne = 2, fl = 1, fi fc = 0.01, and thus N = L/10. Accordingly, if civilizations characteristically destroy themselves within a decade of achieving radio astronomy, which is taken as a marker of an advanced civilization, then N = l, and there are no other intelligent life forms in the Galaxy with whom terrestrial researchers can communicate.

If, on the other hand, it is assumed that one percent of the civilizations learn to live with the technology of mass destruction and themselves, then N = 1,000,000, and the nearest advanced civilization would be on average a few hundred light-years away.

The Drake equation was again brought to the populace at large in the book, Contact by Carl Sagan and in the movie by the same name with Jodie Foster, whose character works with SETI.


While we have discovered a multitude of exo-planets, some the size and apparent composition of Earth, except that observing the tell tale evidence of life still remains just out of reach though it is hoped that the JWST may help in locating these important traces. Yet water, elements associated with life and available sources of energy – appear to be almost everywhere in the Milky Way and farther away. Giant molecular clouds even offer water, elements associated with life like the basic structural unit of DNA and RNA is called a nucleotide which is composed of a nucleobase, a sugar, and a phosphate group. And nucleobases of cytosine, uracil, thymine, adenine, xanthine, and hypoxanthine are commonly found in the interstellar clouds. Yet, with all the foregoing, we have yet to determine which of these eco-planets possess these building blocks.
May 8, 2022
Is there life beyond Earth? So far, the silence is deafening.
There is a possibility that life on earth started very early in the probabilistic range of average evolutionary processes on similar planets.
Any complex life with interstellar communication might have evolved and emerged later than mankind.
Due to the enormous distances and timeframes, any communication may not have arrived yet and that is the same universal silence. "50/50" I'd say.

According to Robert Hazen the prevailing elementary particles that now populate the universe can and do form in many bio-polymers that may result in dynamic replication and evolving molecular complexities.

How many evolutionary paths to becoming living species are "possible" are possible in the vastness of the universe?

As far as we know there are certain fundamental properties that all complex patterns represent and are a universal law.

The definition of a "cell" remains a common property that can be associated with "life".

IMO, at the rate that the universe performs chemistry, it would be only a matter of time before a self-replicating pattern is repeated and "growth " begins.

As Hazen posits; The choice is not between the extremes of numerous events or impossible events, but in the range of probabilities and "enfolded" (Bohm) potentials, numbers that can actually be calculated and falsified.
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It could be that SETI signals have arrived at the Earth, but are lower than the noise level inherent in our receiver systems and the noise from our own Earthly signals pumped into the atmosphere and the cosmos, and our receivers cannot detect them.

Our planet has become so “loud” in the part of the radio spectrum observed by SETI that it threatens to drown out any signal sent from an intelligent civilization.

Radio interference has been a problem for SETI from the very beginning. In the spring of 1960, the planetary scientist Frank Drake trained the massive radio telescope at Green Bank Observatory in West Virginia on Tau Ceti and Epsilon Eridani, two stars a mere 12 light years from Earth. That summer, Drake spent his days studying the signals in the hopes of receiving a message broadcast by an alien civilization orbiting those stars.

Known as Project Ozma, Drake’s experiment marked the beginning of SETI, the scientific search for extraterrestrial intelligence.

Shortly after Drake started his observations, he was surprised to find what appeared to be a signal of intelligent origin. After days of watching a needle drift lazily over a spool of paper recording the random undulations of cosmic static, Drake and his colleagues were jolted awake when the machine started recording the frantic pulses of a strong radio signal picked up by the telescope. The timing and magnitude of the pulses clearly marked them as artificial; there was nothing in the natural world that could produce such a frenetic radio profile. It would have been an astounding stroke of luck to pick up an alien message after only a few hours of observation, but it was hard to argue with the data. “None of us had ever seen anything like it,” Drake recalled in Is Anyone Out There?, his autobiography about the early days of SETI. “We looked at each other wide-eyed. Could discovery be this easy?”

It soon became clear that Drake had discovered an airplane, not an alien civilization drifting noisily through the cosmos with antennas pointed our way.

Our Earth was never a particularly great place to do any kind of radio astronomy due to our thick atmosphere blocking a large portion of the radio spectrum. And the proliferation of radio communication technologies has only made things harder.

Perhaps it's time to look closer at the far side of the Moon, which always faces away from us. The Moon, by comparison, has no atmosphere and its nights last for weeks on end, which serves to limit radio noise from the sun. As NASA discovered through their series of lunar orbiter missions in the late 1960s, the moon also acts as a natural shield that blocks radio signals emanating from Earth. The planetary astronomer Phillipe Zarka said, “the farside of the moon during the lunar night is the most radio-quiet place in our local universe.”

Our Moon possesses exactly the sort of peace and quiet that is desirable if you’re searching for faint radio signals from solar systems and their corresponding exo-planets which may lay hundreds of light years away from us.

To do this listening effectively an orbiter and a radio telescope on the far side are necessary. The basic idea behind a SETI lunar orbiter would be as a repeater of the signals transmitted from the radio telescope as it passed over the lunar far side and then relay data back to Earth as it passed over the near side. One of the main advantages of an orbiter is cost. The proliferation of small satellites that are capable of accurate tracking combined with the rise in numbers of low-cost small launch providers is enticing and more cost effective today than ever before.

While the orbiter would have access to the full sky, the radio telescope on the far side's surface would be constrained by the moon’s rotation unless it was, like most of the Earth's radio telescopes, steerable. The biggest downside to be found with the orbiter is the possible loss of data due to its lack of the Moon's shielding benefits and it will be more vulnerable to radio interference from Earth because it would be orbiting high above the lunar surface.

However, the reduced gravity on the moon would allow for a radio telescope far larger than any on Earth, which could significantly enhance the sensitivity of SETI searches and totally eliminate the Earth's inherent radio noise.

The main drivers are the advent of commercial launch providers like SpaceX, Orbital Sciences, Blue Origin, Sierra Nevada Corp., and Virgin Galactic, which have dramatically lowered the cost of space access, while NASA’s push to establish a permanent human presence on the moon grows as launches to the are quickening their pace and draw ever closer to sending humans there in a permanent colony.

The plans for a lunar SETI observatory would initially require a human settlement on the Moon to build and operate the radio dish. However robotic systems combined with he growth and increasingly complicated AI which have improved enough to take humans out of the SETI monitoring equation altogether. China’s Chang’e 4 rover landed and has operated autonomously on the far side of the Moon. These advancements in autonomous navigation have laid the foundation for a lunar radio observatory that is built entirely by robots and operated by advanced AI and machine learning.

In 2020, Saptarshi Bandyopadhyay offered ideas about using autonomous rovers to deploy wire mesh in a crater on the lunar far side and suspend a receiver over the dish to NASA. NIAC (NASA Advanced Innovative Concepts) is all about funding high risk, high reward missions, while there’s no guarantee that Bandyopadhyay’s proposal will ever come to fruition, simply addressing the technical problems associated with building a radio receiver on the far side of the Moon is an important first step.

Jack Burns, a radio astronomer at the University of Colorado, has also received a grant to study a mission concept for a far side radio telescope array called FARSIDE. Instead of using a crater as a dish, FARSIDE would deploy several smaller antennas across the lunar surface that would collectively form a large radio telescope measured on the baseline between the two farthest radio telescopes from the center.

Both NASA studies are focused on radio astronomy rather than SETI, but the two disciplines as natural allies, who can share use time on the radio telescope system, in the quest to establish an observatory on the lunar far side.




A large radio telescope or a series of smaller telescopes located on the far side of our Moon makes perfect sense to me. Especially since rapid strides are being made in the AI and machine learning necessary to operate them without constant on site human intervention. Without the the threshold of Earth's continual atmospheric problems and its continuous radio noise success in SETI and general radio astronomy would seem to be much more successful.

SETI has attempted to find and prove the existence of technologically advanced intelligence by detecting artificially generated electromagnetic signals for sixty years. While such signals could certainly exist and – given the right circumstances – might be measurable here on Earth, contemporary searches are all compromised by the current limited sensitivity and the need for persistent transmissions. There is also a reasonable conclusion that greater attention to artefact searches could hasten the discovery of alien intelligence when similar AI and its machine learning algorithms are applied to the previously recorded SETI searches.
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May 8, 2022
There is also a reasonable conclusion that greater attention to artefact searches could hasten the discovery of alien intelligence when similar AI and its machine learning algorithms are applied to the previously recorded SETI searches.
AI is going to be invaluable in cosmology.
write4u is correct in his assessment that AI is becoming invaluable and a key tool in cosmology.

“We are spending billions of dollars in ground and space telescopes to decipher the mysteries of the universe,” Villaescusa-Navarro explains, “but we are missing most of the information that the surveys contain,” says Cosmologist Francisco “Paco” Villaescusa-Navarro. Navarro is a research scientist at the Flatiron Institute in New York City. He did his Ph.D. at the University of Valencia in Spain.

The issue is that in any survey, most of the information is at the very smallest scales. For example, if you look at a picture of a forest, you’ll get some information, like a rough idea of how many trees are in there. Once you zoom in a bit, you can see the individual trees and get more information – say, the different species and their heights. If you zoom in even more, the amount of information explodes: You can now determine their age, health, leaf structure, distinct colorings, and more.

Simulations of a large volume of the universe, low resolution, and small bits of the cosmos, high resolution, and a combination of the two created using machine learning programs.

As cosmologists work to unravel mysteries like the nature of dark matter, dark energy, and the expansion history of the universe, they often employ one of their favorite tools: galaxy surveys. These are maps of the positions and velocities of millions of galaxies, and are some of the largest collaborations in the world. For example, the Dark Energy Survey involves over 400 scientists from over 25 institutions across seven countries. While mapping only a relatively tiny fraction of all the contents of the universe, these surveys routinely provide powerful probes of cosmology.

However, almost all cosmology work involves taking these massive surveys and reducing them to comparatively simple statistical summaries, like the average spacing between galaxies or the number of galaxies at different distances. Cosmologists then connect these simple statistical summaries to the quantities they care about, like the amount of dark matter or the expansion rate of the universe.
To squeeze more juice from the cosmological orange, astronomers want to be able to use the smallest possible scales, which contain most of the information in the surveys. But while those small scales contain a lot of rich cosmological information, they are also full of non-cosmological pollution.

“Many people have shown that most of the information about fundamental physics, and also about astrophysics, is on those small scales,” explains Navarro, a research scientist at the Simons Foundation in New York City. “In that regime, it is hard for us to find patterns or even to develop some intuition given the complexity of the physics involved on it.”

All that extra information, like the dynamics of individual galaxies or supernova explosion rates, is great if you’re an astrophysicist, but an annoying contaminant if you’re a cosmologist. Astronomers do not have the sophistication to separate out astrophysical from cosmological information. When two galaxies are interacting in a certain way, for example, is that an imprint from the influence of dark matter or because of feedback from giant black holes?

To separate the information and get to the cosmological signal, we need better astronomers – AI astronomers.

“AI has to potential to find the optimal solution that allow us to extract all the information,” explains Navarro, who has worked with collaborators around the world to develop artificial intelligence methods for cosmology.

But before AI methods can be let loose on the universe, they first must be taught how to be good astronomers.

For that, Navarro and his collaborators turn to simulations. Cosmological simulations incorporate knowledge of all the physics that can possibly be shoved into a single computer and it's software. The expansion rate of the universe, the gravitational tug-of-war that shapes large structures, star formation, explosions from giant black holes, magnetic fields, shock fronts in the intergalactic medium and more all go into a modern simulation.

These simulations aim to reproduce as much of the physics in the real universe as possible and then match those simulations to observations. But with all the messiness of small-scale physics involved, that matching is hard – unless you’re an AI. “This is a simple task for AI, since it will identify patterns and find optimal solutions to problems that we do not know how to treat,” says Navarro.

Navarro and his colleagues produced thousands of simulations, varying all sorts of cosmological parameters (like the amount of dark matter) and astrophysical parameters (like the strength of star formation). Then, they fed these simulations into a type of AI known as a convolutional neural network, which is designed to identify even the most subtle patterns.

“[When we show] the networks many different maps or grids with different cosmologies and astrophysics, the network is learning some pattern that can be used to infer the cosmological parameters,” explains Navarro.

While promising, their work is just beginning. Most importantly, Navarro urges caution, explaining that AI can learn literally anything from these simulations, including patterns and connections that aren’t real, like artifacts from the simulation. To test the AI, it must be run not only on simulations but on existing surveys with known results. Only then can be trusted to provide cosmological information from future datasets.

However, he’s excited for the future. “I think AI is just starting. We are in the phase of exponential growth,” he said, “I personally don’t know how far AI can bring us, but I’m pretty sure things will never be as before.”


Methods based on AI and machine learning have recently made substantial inroads in many corners of cosmology. Through this process, new computational tools, new perspectives on data collection, model development, analysis, and discovery, as well as new communities and educational pathways have emerged. Despite rapid progress, substantial potential at the intersection of cosmology and machine learning remains untapped. It's time to maximize the scientific impact of these increasingly complex and helpful tools over this decade through both technical development as well as the fostering of emerging communities of thought.
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