Celestial Beyond “Fermi’s Paradox” X: What is the Firstborn Hypothesis?

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Beyond “Fermi’s Paradox” X: What is the Firstborn Hypothesis?

In this latest instalment, we explore the possibility that humanity is an early arrival to the Universe, and that intelligent species will become more common with time.

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Posted on September 27, 2020 by Matt Williams

Beyond “Fermi’s Paradox” X: What is the Firstborn Hypothesis?
Welcome back to our Fermi Paradox series, where we take a look at possible resolutions to Enrico Fermi’s famous question, “Where Is Everybody?” Today, we examine the possibility that the reason for the Great Silence is that we are “early to the party”!

In 1950, Italian-American physicist Enrico Fermi sat down to lunch with some of his colleagues at the Los Alamos National Laboratory, where he had worked five years prior as part of the Manhattan Project. According to various accounts, the conversation turned to aliens and the recent spate of UFOs. Into this, Fermi issued a statement that would go down in the annals of history: “Where is everybody?“

This became the basis of the Fermi Paradox, which refers to the disparity between high probability estimates for the existence of extraterrestrial intelligence (ETI) and the apparent lack of evidence. Since Fermi’s time, there have been several proposed resolutions to his question, which includes the Firstborn Hypothesis that states that humanity could be the first intelligent life to emerge in our galaxy.

The Firstborn Hypothesis is similar in some respects to the Hart-Tipler Conjecture and other schools of thought that attribute the “Great Silence” to the fact that humanity is the only advanced species in the known Universe. However, rather than assuming that intelligent life (or life in general) is non-existent, the Firstborn Hypothesis emphasizes that complex life (in all of its forms) has been rare until recently.

Timeline of the Big Bang and the expansion of the Universe. Credit: NASA A Long Time Running
One of the main assumptions behind the Fermi Paradox is that life has had innumerable chances to emerge in our Universe. On the one hand, there is the abundance of space in our galaxy alone, which measures about 200,000 light-years in diameter, contains anywhere from 100 to 400 billion stars, and has an estimated 60 billion planets orbiting within their star’s habitable zone (HZ), 6 billion of which are “Earth-like.”
But then there’s the other all-important dimension, which is time. The Universe has been an estimated 13.8 billion years, the first galaxies existed by 13 billion years ago, and planets began to form shortly thereafter. Considering that our Solar System has only been around for the past 4.6 billion years or so, one would think that life in the Universe has a pretty big head start on Earth-based life forms.

But what if it didn’t? What if we are currently living in a cosmological window where the emergence of life is possible, and in previous epochs, conditions were too harsh for life to exist? Arguments of this nature have been made by many researchers attempting to resolve the Fermi Paradox. In each case, they began with the hypothesis that extraterrestrial life hasn’t had enough time to catch up with us, let alone overtake us.
Anthropic Principle
A key concept that informs this hypothesis is the Anthropic Principle, which is essentially the opposite of the Cosmological Principle (aka. Copernican Principle or “principle of mediocrity”). Whereas the latter assumes that life is typical within the cosmos, which means humanity is not in a unique and special position, the Anthropic Principle states that observations made of the Universe are entirely dependent on its laws being conducive to life.

The phrase itself was coined by theoretical astrophysicist Brandon Carter, who presented the idea during a 1973 symposium in Krakow, Poland, in honor of Copernicus’s 500th birthday. Here, he articulated the principle in response to the Copernican Principle, saying, “Although our situation is not necessarily central, it is inevitably privileged to some extent.”

Specifically, Carter challenged the way the Copernican Principle was being used to justify the idea that all large regions in the Universe (in both space and time) were statistically identical. This notion was central to the Steady State Hypothesis, which had recently been debunked with the discovery of the Cosmic Microwave Background (CMB) radiation. As David Brin would later describe it in the context of the Fermi debate:

“The philosophical counter to the principle of mediocrity is the ‘Anthropic Principle,’ which proposes that it is possible, even in a great and diverse Universe, for an observer to witness a special place and time, especially if the special attribute is required for there to be an observer in the first place… Uniqueness advocates see nothing wrong with the proposal that the intelligent life we see on Earth is rare.”

This principle is central to arguments that assert that humanity is alone in the Universe (or is the first intelligent species to arise in the Milky Way). Basically, it assumes that the Universe exists in a state of disequilibrium, where things have gone from being hostile to conducive to life. Humanity is therefore alive during a transitional phase in the Universe that will be followed by the emergence of many intelligent species.

Origin
While it is difficult to pinpoint the exact source of the Firstborn Hypothesis, many studies have been conducted throughout the years that have hinted at this premise. A solid example is the 1982 study by Lawrence Bracewell – a Professor with the Space, Telecommunications, and Radioscience Laboratory (STAR Lab) at Stanford University – titled “Preemption of the Galaxy by the first advanced civilization.”

In it, Bracewell considered how the first civilizations to emerge in an environment can invariably hold back those that follow. This theory was applied in support of his argument that humanity may be the first advanced civilization to emerge in our galaxy, hence why we haven’t heard from any others. As he summarized:

“[T]errestrial history demonstrates that the advent of one tool-capable and traveling population results in that species’ expansion to all viable territories. The spread of the population occurs in much shorter time than does the evolution of the species, indicating that, perhaps, humans are the first intelligent species in the Galaxy, and may be the future population of the Galaxy.”

If this is true, humanity may want to examine its “planetary protection” protocols and update them. In this case, rather than avoiding areas thought to have microbial life or sterilizing robotic missions to prevent contamination, perhaps we should take a page from the “Zoo Hypothesis” and create quarantine zones around inhabited planets to ensure we don’t interfere with the development of life on them.

Those Deadly GRBs!
James Annis of the Fermi National Accelerator Lab argued something similar in a 1999 study titled “An Astrophysical Explanation for the Great Silence.” According to Annis, periodic gamma-ray bursts (GRBs) could be responsible for limiting the emergence of intelligent life, since they occur at periodic intervals and are powerful enough to cause mass extinctions.

These bursts are the most energetic phenomena in the Universe and occur when massive stars go supernova. The bursts are usually brief (but can be long-lived in the event of a binary companion), emerge from the star’s axis of rotation (aka. polar regions), and be lethal to any planets that lie along their path. In fact, recent research indicates that a GRB may have been responsible for the Ordovician Extinction (ca. 440 million years ago).
Annis employed then-current astrophysical models that suggest that the mean time between GRBs is on the order of 1 billion years. Similarly, evolutionary models used by Annis indicate that this is the same amount of time it takes for intelligence to emerge. This is consistent with the interval between the existence of multi-cellular life and high-order primates (which includes modern humans). As he summarized:

“If one assumes that [GRBs] are in fact lethal to land based life throughout the galaxy, one has a mechanism that prevents the rise of intelligence until the mean time between bursts is comparable to the timescale for the evolution of intelligence…
“Hence, this model suggests that the Galaxy is currently undergoing a phase transition between an equilibrium state devoid of intelligent life to a different equilibrium state where it is full of intelligent life.”

Gamma-ray bursts (GRBs) are powerful flashes of energetic gamma-rays lasting from less than a second to several minutes. Credit: ESO/A. Roquette
In 2008, astronomers Milan M. Cirkovic and Branislav Vukotic of the Astronomical Observatory of Belgrade build upon this argument with a study titled “Astrobiological Phase Transition: Towards Resolution of Fermi’s Paradox.” For their study, Cirkovic and Branislav created a model to test whether or not gamma-ray bursts and other astrobiological regulating mechanisms can periodically “reset” the cosmological clock.

Continued.....

 

[Housecarl]

Continued.....

However, these events occur with exponentially decreasing frequency over time, creating longer and longer windows in which biogenesis (the emergence of life) and noogenesis (the emergence of intelligence) can occur. Overall, their argument employs both the Anthropic Principle and the idea that the Universe is in a phase of disequilibrium. As they stated:

“Secular evolution of regulation mechanisms leads to the brief epoch of phase transition: from an essentially dead place, with pockets of low-complexity life restricted to planetary surfaces, it will, on a short (Fermi–Hart) timescale, become filled with high-complexity life. An observation selection effect explains why we are not, in spite of the very small prior probability, to be surprised at being located in that brief phase of disequilibrium.”

Early to the Party?
A similar argument was made by Prof. Abraham Loeb of the Harvard Smithsonian Center for Astrophysics (CfA) and postdoctoral researchers Rafael A. Batiste and David Sloan (of the University of Oxford). In this study, titled “Relative Likelihood for Life as a Function of Cosmic Time,” Loeb and his colleagues calculated the probability of habitable Earth-like planets forming within a certain volume of space over time.

Beginning with the first stars, which formed roughly 30 million years after the Big Bang, and continuing into the distant future, they found that the emergence of life (as we know it) is directly dependent on the mass of the star involved and increases in probability over longer stretches of time. Essentially, high-mass stars have a shorter life-span, which means they likely die before life can emerge on any planets orbiting them.

Lower mass stars like M-type red dwarfs have much longer lifespans and can remain in their main sequence phase for up to twelve trillion years. Ultimately, Loeb and his colleagues confirmed that planets orbiting red dwarf stars (barring factors that would suppress their potential habitability) are much more likely to support life over longer timescales. Or as Leob said in a CfA press statement issued coincidentally with the study:

“If you ask, ‘When is life most likely to emerge?’ you might naively say, ‘Now’. But we find that the chance of life grows much higher in the distant future. So then you may ask, why aren’t we living in the future next to a low-mass star? One possibility is we’re premature. Another possibility is that the environment around a low-mass star is hazardous to life.”

Criticisms
If we follow this logic, then the reason there is such a thing as the “Great Silence” is that until recently, the Universe was not particularly conducive to intelligent life. While simple life may be plentiful, the timescales between gamma-ray bursts or other astrobiological regulating mechanisms have been too short to allow for intelligent life to emerge. From an evolutionary and cosmological standpoint, this certainly makes sense.

Artist’s impression shows the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. Credit: ESO/M. Kornmesser
Naturally, critics of this hypothesis would cite that it is not only Anthropic in its outlook but anthropocentric. While it seems presumptuous to assume that the evolution of life in our galaxy (or the Universe) would follow a similar trajectory as humanity’s, it is similar to assume that humanity would be the only intelligent species to develop communication technologies that could be detected from space.

Another issue arising from this hypothesis is the fact that it is very difficult to test. While remote sensing techniques would be capable of confirming the presence of life through the detection of biosignatures, they would not be able to determine whether that life is intelligent or not. This is what is often referred to as the “algae vs. alumnae” problem.
And of course, there’s the assumption that GRBs are becoming less common with time. At present, there is no definitive evidence that these bursts have become less common since Earth formed roughly 4.5 billion years ago. In fact, some estimates claim that as many as 1,000 GRBs have taken place close enough to Earth to affect life since it began 4 billion years ago.
Even if every single extinction event in Earth’s history could be linked to GRBs, it clearly didn’t prevent the emergence of intelligent life. In the end, the Firstborn Hypothesis is not unlike most theories that fall into the Great Filter, with the filter being applied either somewhere in the middle or many times over the course of a planet’s history.

Artist’s impression of the Milky Way’s structure. Credit: ESA
In the end, a key assumption of the Fermi Paradox is that ETIs should have expanded beyond their star system and left undeniable traces of their existence by now. The fact that we can’t find any is seen as an indication that they must not exist. But what if this is a simple case of preemption, where humanity is the first (or one of the first) to emerge in our galaxy?
Rather than deterring us from investigating further, this theory invites us to keep looking – if for no other reason, than to confirm that we are the only current technologically-advanced species. If humanity is “early to the party,” it gives us a chance to do the kinds of things that we’ve long-speculated more advanced species would do.
We could play God, tamper with evolution, uplift species that are on the verge of sentience, or inhibit their development. Or, as a radical alternative, we could act responsibly for a change! If humanity’s place in the Universe is somehow special and privileged, then we should behave the way we would want a more advanced species to behave towards us.

We have written many interesting articles about the Fermi Paradox, the Drake Equation, and the Search for Extraterrestrial Intelligence (SETI) here at Universe Today.
Here’s Where Are The Aliens? How The ‘Great Filter’ Could Affect Tech Advances In Space, Why Finding Alien Life Would Be Bad. The Great Filter, How Could We Find Aliens? The Search for Extraterrestrial Intelligence (SETI), and Fraser and John Michael Godier Debate the Fermi Paradox.
And be sure to check out the rest of our Beyond Fermi’s Paradox series:

• Beyond “Fermi’s Paradox” I: A Lunchtime Conversation- Enrico Fermi and Extraterrestrial Intelligence
• Beyond “Fermi’s Paradox” II: Questioning the Hart-Tipler Conjecture
• Beyond “Fermi’s Paradox” III: What is the Great Filter?
• Beyond “Fermi’s Paradox” IV: What is the Rare Earth Hypothesis?
• Beyond “Fermi’s Paradox” V: What is the Aestivation Hypothesis?
• Beyond “Fermi’s Paradox” VI: What is the Berserker Hypothesis?
• Beyond “Fermi’s Paradox” VII: What is the Planetarium Hypothesis?
• Beyond “Fermi’s Paradox” VIII: What is the Zoo Hypothesis?
• Beyond “Fermi’s Paradox” IX: What is the Brief Window Hypothesis?

Astronomy Cast has some interesting episodes on the subject. Here’s Episode 24: The Fermi Paradox: Where Are All the Aliens?, Episode 110: The Search for Extraterrestrial Intelligence, Episode 168: Enrico Fermi, Episode 273: Solutions to the Fermi Paradox.
Sources:

• “The Anthropic Principle and the Structure of the Physical World.” Nature Vol. 278 (1979)
• Bracewell, R. “Preemption of the Galaxy by the First Advanced Civilization.” in Extraterrestrial – Where are They? Pergmon Press, Oxford (1982)
• Brin, G.D. “The Great Silence – the Controversy Concerning Extraterrestrial Intelligent Life.” Quarterly Journal of the Royal Astronomical Society, Vol. 24 (1983)
• Annis, J. “An Astrophysical Explanation for the Great Silence.” Journal of the British Interplanetary Society. Vol. 52 (1999)
• Cirkovic, M.M. & Branislav, V. “Astrobiological Phase Transition: Towards Resolution of Fermi’s Paradox.” Origins of Life and Evolution of Biospheres, Vol. 38 (2008)
• Melott, A. L. (et al.) “Did a gamma-ray burst initiate the late Ordovician mass extinction?” International Journal of Astrobiology, Vol. 3, No. 55 (2004)
• Hair, T. W. “Temporal Dispersion of the Emergence of Intelligence: an Inter-Arrival Time Analysis.” International Journal of Astrobiology, Vol. 10 , No. 2 (2011)
• Loeb, A. (et al.) “Relative Likelihood for Life as a Function of Cosmic Time.” Journal of Cosmology and Astroparticle Physics, Vol. 8 (2016)

 

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Maybe There Are Just Very Few Aliens Out There…

Even if life is rare in the universe, Earth may be uniquely suited to space exploration, as the Privileged Planet hypothesis suggests.

mindmatters.ai

Maybe There Are Just Very Few Aliens Out There…
The Rare Earth hypothesis offers science-based reasons that life in the universe is rare News October 10, 2020
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Recently, science and science fiction writer Matt Williams has been writing a series at Universe Today on why extraterrestrial intelligences never make contact with us.

Last week, we looked at the hypothesis that, to avoid the heat destruction of their advanced technology, the aliens have put themselves into a digital slumber until the universe cools down.

This week, let’s look at a quite different approach, which Williams outlines in “Beyond “Fermi’s Paradox” IV: What is the Rare Earth Hypothesis?” (July 29, 2020): That is “the possibility that life-bearing planets like Earth are just very rare.” We don’t see aliens because they are very uncommon:

This is what is popularly known as the “Rare Earth Hypothesis,” which argues that the emergence of life and the evolution of complexity require a combination of astrophysical and geological conditions that are simply not common in our Universe. This contradicted previously-held notions by prominent scientists and SETI researchers, who were of the opinion that Earth was typical of rocky planets located throughout the Universe.
Matt Williams, “Beyond “Fermi’s Paradox” IV: What is the Rare Earth Hypothesis?” at Universe Today

As Williams points out, the term “Rare Earth”* was popularized by an influential 2003 book called Rare Earth: Why Complex Life is Uncommon in the Universe. It’s authors are paleontologist Peter Ward and astronomer Donald E. Brownlee at the University of Washington.

The duo questioned a central assumption made by Carl Sagan (1934–1996), Frank Drake and the (and Search for Extraterrestrial Intelligence ’s) iconic Drake Equation: of 1961, that not only are They Out There but there are Lots of Them.

Ward and Brownlee revised their famous Equation and added in factors known to be true of Earth but maybe not easy to find elsewhere and came up with a much lower figure:



For a number of reasons, Matt Williams does not like the Rare Earth hypothesis. Concluding a list, he writes:

On top of all that, scientists have questioned the definition of “habitable zone” in recent years, with some suggesting it could be a lot narrower than previously thought. Other research has indicated that habitable planets could also be found in longer orbits, indicating that HZs are actually wider. It’s also possible that Earth does not represent the pinnacle of habitability and there may be a class of “superhabitable” worlds.
Considerable research has also been dedicated to how our very notion of habitability is based entirely on Earth’s current geological period. At many junctures in the past, atmospheric and climatic conditions were significantly different on Earth than they are today. And yet, these conditions are believed to have been essential to the evolution of life at different stages.
Matt Williams, “Beyond “Fermi’s Paradox” IV: What is the Rare Earth Hypothesis?” at Universe Today

Of course, no one can rule out the possibility that entities that we would not recognize as life but really are life exist in abundance in the universe. For one thing, there are many definitions of “life” as we do know it:

Abstract: Despite numerous and increasing attempts to define what life is, there is no consensus on necessary and sufficient conditions for life. Accordingly, some scholars have questioned the value of definitions of life and encouraged scientists and philosophers alike to discard the project. As an alternative to this pessimistic conclusion, we argue that critically rethinking the nature and uses of definitions can provide new insights into the epistemic roles of definitions of life for different research practices.
– Bich, Leonardo and Green, Sara (2016) Is defining life pointless? Operational definitions at the frontiers of Biology. Synthese. ISSN 1573-0964

But the Drake Equation that is our starting point addresses the question in terms of accepted assumptions about the elements and conditions needed for life. Departing too far from those terms may render the problem both undefinable and unresearchable.

A critic at Futurism points out that life forms are adaptable:

Over millions of years, species have evolved to adapt to their environment. We have fish and other exotic forms of life that can survive under immense pressures within the deepest depths on the ocean floor. We have algae that can survive in boiling temperatures. Then, we have the lovely tardigrades (also known as water bears), which can survive IN THE VACUUM OF SPACE.
So life could thrive in environments much different than that of our own blue marble. On top of this, there are more and more Earth-like exoplanets being discovered each day, just within our galaxy alone. This doesn’t necessarily mean that Earth-like life has a fighting chance on any of them, but it also doesn’t mean that there never will be!
“The Rare Earth Hypothesis” at Futurism (May 4, 2014)

Indeed, but the whole concept of adaptability is defined on life forms considered as descendants of Earth. It does not by itself imply that there are any others out there.

The underlying principle that Williams and Futurism defend—in opposition to the Rare Earth Principle (or hypothesis)—is the Principle of Mediocrity:

In this astonishing world view, our Earth and our civilization are anything but unique. Instead, countless identical civilizations are scattered across the infinite expanse of the cosmos. With humankind reduced to absolute cosmic insignificance, our descent from the center of the world, a process begun by Copernicus, is now complete.
Alexander Vilenkin, “The Principle of Mediocrity” at Edge

As Vilenkin implies, the Principle is sometimes called the “Copernican Principle” though the 16th century astronomer Copernicus, who developed the Sun-centred concept of the solar system, was not involved. But the Principle, whichever we call it, is closely related to the origin of the Drake Equation, as illustrated in this excerpt from Carl Sagan’s Pale Blue Dot, responding to the Earth images taken by Voyager I on February 14, 1990:

It had been well understood by the scientists and philosophers of classical antiquity that the Earth was a mere point in a vast, encompassing cosmos—but no one had ever seen it as such. Here was our first chance, and perhaps also our last for decades to come.
… Because of the reflection of sunlight off the spacecraft, the Earth seems to be sitting in a beam of light, as if there were some special significance to this small world; but it’s just an accident of geometry and optics. There is no sign of humans in this picture: not our reworking of the Earth’s surface; not our machines; not ourselves. From this vantage point, our obsession with nationalisms is nowhere in evidence. We are too small. On the scale of worlds, humans are inconsequential: a thin film of life on an obscure and solitary lump of rock and metal.
Carl Sagan, “The World Would Be Better If Everyone Watched This Video” quoted at Gizmodo (December 4, 2010)

Drake and Sagan chose to believe, on that evidence, that extraterrestrial civilizations are plentiful in the universe. But that’s a choice. The total silence can equally suggest that we are a lone cosmic accident.

A third approach is the Privileged Planet hypothesis, according to which “the same narrow circumstances that allow us to exist also provide us with the best overall setting for making scientific discoveries.” This is, of course, one of the intelligent design hypotheses, according to which the universe is designed by an intelligent agent. Also, because we are intelligent agents ourselves, we have been situated so as to enable discovery. In the abstract of an open access paper, astronomer Guillermo Gonzalez explains,

It is easier to launch an interstellar spacecraft from a planet in the circumstellar habitable zone of the Sun than from planets in the circumstellar habitable zones of less massive stars. In the larger context of the Milky Way galaxy, our Solar System is in the best location to initiate interstellar missions. In summary, we here confirm and expand upon recent studies that argue that the Earth and the Solar System are rare in the degree to which they facilitate space exploration.
Gonzalez G (2020) The solar system: Favored for space travel. BIO-Complexity 2020(1):1–8. doi:10.5048/BIO-C.2020.1.

Further:

Although we have focused on space travel from super-Earths in the present work, it should be obvious that space travel from planets smaller than Earth should be easier, up to a point. Below some minimum mass, a terrestrial planet cannot maintain liquid water on the surface. However, it seems odd that the Earth is near the upper limit in mass for manned space travel.
Earth, in particular, provides its inhabitants clear views of the sun, moon, planets, and stars. Water, which is essential for life processes and for making Earth a habitable planet, also contains the two elemental ingredients needed for one of the best rocket propellants. Earth’s crust contains the minable mineral and fossil fuel resources needed for a high-tech civilization, including the construction of rockets. Earth’s planetary neighbors provide gravity assists to help spacecraft escape the Solar System. Even Earth’s location in the Milky Way galaxy seems to be optimal for interstellar travel. Earth is much better for space travel than the many less habitable exoplanetary super-Earths that have been discovered.
Gonzalez G (2020) The solar system: Favored for space travel. BIO-Complexity 2020(1):1–8. doi:10.5048/BIO-C.2020.1.

Agree/disagree with the Privileged Planet hypothesis? Your choice. But don’t dismiss our Earthling advantages if you are trying to persuade a politician to vote more money for space science research. On the other hand, when we do the research, we are stuck with what we find—even if it includes minimal aliens. There is at least a good chance, if the Privileged Planet hypothesis is true, that one day we might really know the answers. Maybe we were Intended and Expected to find them out…

Note: The term rare earth can also refer to a group of 15 elements referred to as the lanthanide series in the periodic table of elements that are key components in many electronic devices.


You may also enjoy:

1.Are the Aliens We Never Find Obeying Star Trek’s Prime Directive? The Directive is, don’t interfere in the evolution of alien societies, even if you have good intentions. Assuming the aliens exist, perhaps it’s just as well, on the whole, if they do want to leave us alone. They could want to “fix” us instead…

2.How can we be sure we are not just an ET’s simulation? A number of books and films are based on the idea. Should we believe it? We make a faith-based decision that logic and evidence together are reasonable guides to what is true. Logical possibility alone does not make an idea true.

3.Did the smart machines destroy the aliens who invented them? That’s the Berserker hypothesis. A smart deadly weapon could well decide to do without its inventor and, lacking moral guidance, destroy everything in sight. Extinction of a highly advanced civilization by its own lethal technology may be more likely than extinction by natural disaster. They could control nature.

and

4.Researchers: The aliens exist but they are sleeping… And we wake them at our peril. The Aestivation hypothesis is that immensely powerful aliens are waiting in a digitized form for the universe to cool down from the heat their computers emit.

 

[Housecarl]

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For linked videos please see article source....

Massive Hunt for Extraterrestrial Life Completed: What Astronomers Found in Search of 10 Million Star Systems for Alien Technology

A radio telescope in outback Western Australia has completed the deepest and broadest search at low frequencies for alien technologies, scanning a patch of sky known to include at least 10 million stars. Astronomers used the Murchison Widefield Array (MWA) telescope to explore hundreds of times m

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Massive Hunt for Extraterrestrial Life Completed: What Astronomers Found in Search of 10 Million Star Systems for Alien Technology
TOPICS:AstrobiologyAstronomyAstrophysicsInternational Centre for Radio Astronomy ResearchPopular

By International Centre for Radio Astronomy Research September 19, 2020


The Murchison Widefield Array radio telescope, a portion of which is pictured here, was used to explore hundreds of times more broadly than any previous search for extraterrestrial life. Credit: Goldsmith/MWA Collaboration/Curtin University
A radio telescope in outback Western Australia has completed the deepest and broadest search at low frequencies for alien technologies, scanning a patch of sky known to include at least 10 million stars.

Astronomers used the Murchison Widefield Array (MWA) telescope to explore hundreds of times more broadly than any previous search for extraterrestrial life.
The study, published this month in Publications of the Astronomical Society of Australia, observed the sky around the Vela constellation. But in this part of the Universe at least, it appears other civilizations are elusive, if they exist.
The research was conducted by CSIRO astronomer Dr. Chenoa Tremblay and Professor Steven Tingay, from the Curtin University node of the International Centre for Radio Astronomy Research (ICRAR).

Dipole antennas of the Murchison Widefield Array (MWA) radio telescope in Mid West Western Australia. Credit: Dragonfly Media
Dr. Tremblay said the telescope was searching for powerful radio emissions at frequencies similar to FM radio frequencies, which could indicate the presence of an intelligent source.
These possible emissions are known as ‘technosignatures.’
“The MWA is a unique telescope, with an extraordinarily wide field-of-view that allows us to observe millions of stars simultaneously,” she said.
“We observed the sky around the constellation of Vela for 17 hours, looking more than 100 times broader and deeper than ever before.
“With this dataset, we found no technosignatures—no sign of intelligent life.”

Tile 107, or “the Outlier” as it is known, is one of 256 tiles of the MWA, located 1.5km from the core of the telescope. Lighting the tile and the ancient landscape is the Moon. Credit: Pete Wheeler, ICRAR
Professor Tingay said even though this was the broadest search yet, he was not shocked by the result.
“As Douglas Adams noted in The Hitchhikers Guide to the Galaxy, ‘space is big, really big’.”
“And even though this was a really big study, the amount of space we looked at was the equivalent of trying to find something in the Earth’s oceans but only searching a volume of water equivalent to a large backyard swimming pool.
“Since we can’t really assume how possible alien civilizations might utilize technology, we need to search in many different ways. Using radio telescopes, we can explore an eight-dimensional search space.
“Although there is a long way to go in the search for extraterrestrial intelligence, telescopes such as the MWA will continue to push the limits—we have to keep looking.”
The MWA is a precursor for the instrument that comes next, the Square Kilometre Array (SKA), a 1.7 billion Euro observatory with telescopes in Western Australia and South Africa. To continue the Douglas Adams references, think of the MWA as the city-sized Deep Thought and the SKA as its successor: the Earth.

A time-lapse sequence of more than 1,000 images captured at the Murchison Radio-astronomy Observatory in Mid West WA. Tile 107, or “the Outlier” as it is known, is one of 256 tiles of this Square Kilometre Array precursor instrument located 1.5km from the core of the telescope. Lighting the tile and the ancient landscape is the Moon. Credit: Pete Wheeler / ICRAR
“Due to the increased sensitivity, the SKA low-frequency telescope to be built in Western Australia will be capable of detecting Earth-like radio signals from relatively nearby planetary systems,” said Professor Tingay.
“With the SKA, we’ll be able to survey billions of star systems, seeking technosignatures in an astronomical ocean of other worlds.”
The MWA is located at the Murchison Radio-astronomy Observatory, a remote and radio quiet astronomical facility established and maintained by CSIRO—Australia’s national science agency. The SKA will be built at the same location but will be 50 times more sensitive and will be able to undertake much deeper SETI experiments.
Reference: ‘”A SETI Survey of the Vela Region using the Murchison Widefield Array: Orders of Magnitude Expansion in Search Space” by C. D. Tremblay and S. J. Tingay, 8 September 2020, Publications of the Astronomical Society of Australia (PASA).
DOI: 10.1017/pasa.2020.27
Acknowledgments
A consortium of partner institutions from seven countries (Australia, USA, India, New Zealand, Canada, Japan, and China) financed the development, construction, commissioning, and operations of the Murchison Widefield Array radio telescope. The consortium is led by Curtin University.
We acknowledge the Wajarri Yamatji as the traditional owners of the Murchison Radio-astronomy Observatory site.
We acknowledge the Pawsey Supercomputing Centre which is supported by the Western Australian and Australian Governments.

 

[Housecarl]

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How many alien civilizations are out there? Believe it or not, there’s a calculator that answers the question

In June, The Astrophysical Journal had a story that said not only do aliens exist, there’s a whole lot of them out there.

www.pennlive.com

1. Pennsylvania Real-Time News

How many alien civilizations are out there? Believe it or not, there’s a calculator that answers the question
Posted Aug 15, 2020

By Brian Linder | blinder@pennlive.com
We’ve all heard the creepy alien abduction tales, and some of us have seen unexplained things in the sky.
So, are we alone in the universe? Do aliens exist?
The Pentagon is forming a task force to look into that — or at least, UFOs, which aren’t necessarily aliens but could be — according to a report this week.
And, in June, The Astrophysical Journal had a story that said not only do aliens exist, there’s a whole lot of them out there.

How many alien civilizations could there possibly be, though?

Believe it or not, there’s a calculator for that.

Alien Civilization Calculator

Introduction
This calculator compares two methods which attempt to estimate how many alien civilizations there could be in the Milky Way Try comparing the two models and see how their results differ, then experiment by changing their values. How many ETs are really out there?
Model selection
Mod.
Astrobiol. Copernican Princ.

Find out all about the Astrobiological Copernican Principle here.
Milky Way assumptions
Modeling scenario
Strong


Number of stars (N⁕)
billion

Mature stars (fL)
%

Habitable zone (fHZ)
%

Metallicity (fM)
%

Available time (τ′)
billion yrs

Lifetime of signals (L)
yrs

Results
Number of civilizations (N)


Maximum distance to nearest
17,000
ly


The Astrobiological Copernican Principle model says that there may be 36 advanced alien civilizationsout there in the Milky Way (with a large uncertainty).
If they are spread out evenly across the Milky Way, the maximum distance to our nearest neighbor would be 17,000 light-years. Our space travel calculator can help plan your trip!
Chance of aliens vs. distance
Distance
ly


Enter a distance above ☝ to calculate the probability that an alien civilization exists within this distance from Earth.

Now try the other model
Select the Drake equation model back at the top of the calculator to see how it compares.



CAN’T SEE THE CALCULATOR ABOVE? CLICK HERE.

The Alien Civlization Calculator is a thing over at the Omni Calculator Project and it’s based on the Astrobiological Copernican Principle and on the Drake Equation, according to its designer.

The Drake Equation takes the number of habitable planets and multiplies it by the likelihood of a technological species arising on one of those planets. The Astrobiological Copernican Principle states that humans are not privileged observes of the universe.

Seems a bit fuzzy, but the calculator uses both to come up with its results.

And, it too suggests we are not alone.

In fact, according to its developer, “the chances of finding aliens 10 light-years away are higher than winning a Mega Millions Jackpot (1 in 217 million vs. 1 in 302 million).”

The Astrophysical Journal predicted there could be “at least 36 intelligent alien civilizations in our galaxy.”

How’d they come up with “at least 36?”

Well, according to Forbes, scientists at the University of Nottingham came up with a new “cosmic evolution” based calculation that suggested it.

The Milky Way, it said, Is estimated to have between 100 billion to 400 billions stars, and “roughly one exoplanet per star in our galaxy.”

Then again, perhaps, there aren’t 36 out there after all.

That’s because the calculation makes “a lot of assumptions,” according to the report.

For instance, it assumes that life may occur on other planets like it has on ours. That’s not a given, obviously.

Another “key assumption,” according to the report is that it takes “around five billion years for intelligent life to form on other planets, as it does on Earth, but that life is probable.”

Another assumption, the report said, is that a race with technology would last 100 years, such as ours. That’s also, obviously, not a given.

Check out the calculator above and see how it compares and, perhaps, get an idea of just how many. “visitors” may be making their way to or have, perhaps, already made their way to our little spinning rock.

 

[Publius]

Seems to be some evidence we have been visited in the long ago past and within the last 70 years.

 

[Housecarl]

Seems to be some evidence we have been visited in the long ago past and within the last 70 years.

And as soon as they saw what was going on they got the hell out of here......

 

[jward]

Oh my. Such a packed post deserves time to digest. There's a semester's worth of work therein, minimum. Will be good thought food to stave off the chill of winter. I find myself disinclined to thought now, though, when so many delightful images distract and enchant. For now, I'll just content myself oohing and ahhing over them. :: happy dance ::

..still, i have never grasped why we predicate our search for otherness based on our life form or technologies. surely whatever force capable of dreaming you and I into existence has the capacity to dream other dreams simultaneously. :: shrug :: Still, there's a wee bit of comfort in the thought that we could be first to the party; Lord help us if this rude and rudimentary human condition is the pinnacle.

 

[Oreally]

Thanks for posting this HC.

lol. i have old friends and lovers, intelligent people, who get furious with me for even suggesting this.

that we may not only be alone, but are the first seed stock...