This Hubble Space Telescope image shows the massive galaxy cluster MACS J1206. Embedded within the cluster are the distorted images of distant background galaxies, seen as arcs and smeared features. These distortions are caused by the amount of dark matter in the cluster, whose gravity bends and magnifies the light from faraway galaxies. This effect, called gravitational lensing, allows astronomers to study remote galaxies that would otherwise be too faint to see.
Astronomers measured the amount of gravitational lensing in the cluster to produce a detailed map of the cluster’s distribution of dark matter. This elusive substance is the invisible glue that keeps stars bound together inside a galaxy and makes up the bulk of the universe’s matter. Galaxy clusters are the largest repository of dark matter in the universe.
In addition to the dark matter smoothly distributed within the cluster, astronomers found that an expectedly large amount of it is concentrated in individual cluster galaxies. These concentrations produced gravitational lensing effects that are 10 times stronger than theory predicts.
Several of these galaxies are sufficiently massive and dense to also distort and magnify faraway sources. The galaxies in the three pullouts represent examples of such effects. In the snapshots at upper right and bottom, two distant, blue galaxies are lensed by the foreground redder cluster galaxies, forming rings and multiple images of the remote objects. The red blobs around the galaxy at upper left denote emission from clouds of hydrogen in a single distant source. The source, seen four times because of lensing, may be a faint galaxy. These blobs were detected by the Multi-Unit Spectroscopic Explorer (MUSE) at the European Southern Observatory’s Very Large Telescope (VLT) in Chile. The blobs do not appear in the Hubble images.
MACS J1206 is part of the Cluster Lensing And Supernova survey with Hubble (CLASH) program and is one of three galaxy clusters the researchers studied with Hubble and the VLT.
The researchers suggest that this mismatch is either some physical ingredient that is missing in how the computer simulations are created or in astronomers’ understanding of the nature of dark matter that shapes the formation and evolution of cluster galaxies.
The Hubble image is a combination of visible- and infrared-light observations taken in 2011 by the Advanced Camera for Surveys and Wide Field Camera 3.
NASA, ESA, P. Natarajan (Yale University), G. Caminha (University of Groningen), M. Meneghetti (INAF-Observatory of Astrophysics and Space Science of Bologna), and the CLASH-VLT/Zooming teams Acknowledgement: NASA, ESA, M. Postman (STScI), and the CLASH team
About The Object
MACS J1206.2-0847, MACS 1206
4.5 billion light-years (1.2 billion parsecs)
Image is 2.25 arcmin across (about 2 billion light-years)
About The Data
This image was created from HST data from proposal 12069: M. Postman (STScI) et al.
This image is a composite of many separate exposures made by the ACS and WFC3 instruments on the Hubble Space Telescope using ten different filters. The color results from assigning different hues (colors) to each monochromatic image. In this case, the assigned colors are: Blue: ACS/WFC F435W (B), F475W (g), F606W (V) + F625W (r) Green: ACS/WFC F775W (i) + F814W (I) + F850LP (z) Red: WFC3/IR F105W (Y) + F110W (YJ) + F125W (J) + F140W (JH) + F160W (H) This image includes an overlay showing Lyman-alpha data from the ESO/VLT MUSE instrument in magenta.
RESEARCHERS FIND A SURPRISING GAP BETWEEN DARK MATTER OBSERVATIONS AND THEORIES
While studying the Coma galaxy cluster in 1933, astronomer Fritz Zwicky uncovered a problem. The mass of all the stars in the cluster added up to only a few percent of the heft needed to keep member galaxies from escaping the cluster’s gravitational grip. He predicted that the “missing mass,” now known as dark matter, was the glue that was holding the cluster together.
Dark matter, as its name implies, is matter that cannot be seen. It does not emit, absorb, or reflect light, nor does it interact with any known particles. The presence of these elusive particles is only known through their gravitational pull on visible matter in space. This mysterious substance is the invisible scaffolding of our universe forming long filamentary structures—the cosmic web—along which galaxies form.
Even more confounding is that dark matter makes up the vast bulk of the universe’s overall mass content. The stuff that stars, planets, and humans are made of accounts for just a few percent of the universe’s contents.
Astronomers have been chasing this ghostly substance for decades but still don’t have many answers. They have devised ingenious methods to infer dark matter’s presence by tracing the signs of its gravitational effects.
One technique involves measuring how dark matter’s gravity in a massive galaxy cluster magnifies and warps light from a distant background galaxy. This phenomenon, called gravitational lensing, produces smeared images of remote galaxies and occasionally multiple copies of a single image.
A recent study of 11 hefty galaxy clusters found that some small-scale clumps of dark matter are so concentrated that the lensing effects they produce are 10 times stronger than expected. These concentrations are associated with individual cluster galaxies.
Researchers using the Hubble Space Telescope and the European Southern Observatory’s Very Large Telescope in Chile discovered with unprecedented detail smaller-scale distorted images of remote galaxies nested like Matryoshka dolls within the larger-scale lens distortions in each cluster’s core, where the most massive galaxies reside.
This unexpected discovery means there is a discrepancy between these observations and theoretical models of how dark matter should be distributed in galaxy clusters. It could signal a gap in astronomers’ current understanding of the nature of dark matter.
Astronomers have discovered that there may be a missing ingredient in our cosmic recipe of how dark matter behaves.
They have uncovered a discrepancy between the theoretical models of how dark matter should be distributed in galaxy clusters, and observations of dark matter’s grip on clusters.
Dark matter does not emit, absorb, or reflect light. Its presence is only known through its gravitational pull on visible matter in space. Therefore, dark matter remains as elusive as Alice in Wonderland’s Cheshire Cat–where you only see its grin (in the form of gravity) but not the animal itself.
One way astronomers can detect dark matter is by measuring how its gravity distorts space, an effect called gravitational lensing.
Researchers found that small-scale concentrations of dark matter in clusters produce gravitational lensing effects that are 10 times stronger than expected. This evidence is based on unprecedently detailed observations of several massive galaxy clusters by NASA’s Hubble Space Telescope and the European Southern Observatory’s Very Large Telescope (VLT) in Chile.
Galaxy clusters, the most massive structures in the universe composed of individual member galaxies, are the largest repositories of dark matter. Not only are they held together largely by dark matter’s gravity, the individual cluster galaxies are themselves replete with dark matter. Dark matter in clusters is therefore distributed on both large and small scales.
“Galaxy clusters are ideal laboratories to understand if computer simulations of the universe reliably reproduce what we can infer about dark matter and its interplay with luminous matter,” said Massimo Meneghetti of the INAF (National Institute for Astrophysics)-Observatory of Astrophysics and Space Science of Bologna in Italy, the study’s lead author.
“We have done a lot of careful testing in comparing the simulations and data in this study, and our finding of the mismatch persists,” Meneghetti continued. “One possible origin for this discrepancy is that we may be missing some key physics in the simulations.”
Priyamvada Natarajan of Yale University in New Haven, Connecticut, one of the senior theorists on the team, added, “There’s a feature of the real universe that we are simply not capturing in our current theoretical models. This could signal a gap in our current understanding of the nature of dark matter and its properties, as these exquisite data have permitted us to probe the detailed distribution of dark matter on the smallest scales.”
The team’s paper will appear in the Sept. 11 issue of the journal Science.
The distribution of dark matter in clusters is mapped via the bending of light, or the gravitational lensing effect, they produce. The gravity of dark matter magnifies and warps light from distant background objects, much like a funhouse mirror, producing distortions and sometimes multiple images of the same distant galaxy. The higher the concentration of dark matter in a cluster, the more dramatic its light bending.
Hubble’s crisp images, coupled with spectra from the VLT, helped the team produce an accurate, high-fidelity dark-matter map. They identified dozens of multiply imaged, lensed, background galaxies. By measuring the lensing distortions, astronomers could trace out the amount and distribution of dark matter.
To the team’s surprise, the Hubble images also revealed smaller-scale arcs and distorted images nested within the larger-scale lens distortions in each cluster’s core, where the most massive galaxies reside.
The researchers believe that the embedded lenses are produced by the gravity of dense concentrations of dark matter associated with individual cluster galaxies. Dark matter’s distribution in the inner regions of individual galaxies is known to enhance the cluster’s overall lensing effect.
Follow-up spectroscopic observations added to the study by measuring the velocity of the stars orbiting inside several of the cluster galaxies. “Based on our spectroscopic study, we were able to associate the galaxies with each cluster and estimate their distances,” said team member Piero Rosati of the University of Ferrara in Italy.
“The stars’ speed gave us an estimate of each individual galaxy’s mass, including the amount of dark matter,” added team member Pietro Bergamini of the INAF-Observatory of Astrophysics and Space Science in Bologna, Italy.
The team compared the dark-matter maps with samples of simulated galaxy clusters with similar masses, located at roughly the same distances as the observed clusters. The clusters in the computer simulations did not show the same level of dark-matter concentration on the smallest scales–the scales associated with individual cluster galaxies as seen in the universe.
The team looks forward to continuing their stress-testing of the standard dark-matter model to pin down its intriguing nature.
NASA’s planned Nancy Grace Roman Space Telescope will detect even more remote galaxies through gravitational lensing by massive galaxy clusters. The observations will enlarge the sample of clusters that astronomers can analyze to further test the dark-matter models.
The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.
NASA, ESA, P. Natarajan (Yale University), M. Meneghetti (INAF-Observatory of Astrophysics and Space Science of Bologna), P. Rosati (University of Ferrara), and the CLASH-VLT/Zooming teams Acknowledgement: NASA, ESA, M. Postman (STScI), and the CLASH team
The COVID-19 pandemic that hit the world in 2020 brought many changes to all of our lives, including the tragic deaths of people we knew and loved. Meanwhile, even for those of us who were not directly affected by the disease, the uncertainty that it brought to our lives was a constant worry. Fear arises from uncertainty.
Science tries to put constraints on that fear by at least letting us know what is likely, or not likely, to occur. This was the motivation behind the desire of every civilization to outline the shape of the coming year with calendars. Astronomy was developed and supported by our ancient cultures precisely to give us the reassurance that spring would follow winter, and to remind us to be prepared when winter would come again.
As our knowledge of the sky grew and we learned even how to predict the motions of the planets, wandering among those stars, it was tempting (if ultimately fruitless) to hope that we could use that ability to somehow give us a comforting foreknowledge of things to come here on Earth. Still, even if astrology was ultimately found wanting, the repeatable sequence of the stars through the seasons which astronomy taught us could be a source of reassurance in an uncertain universe.
Donati’s Comet of 1859; drawing by William Turner. Comets are frightening because they are unpredictable…
But along with letting us know about the usual seasons of the year, a calendar can also remind us of the days when something unusual did happen: the birth or death of a notable person, the remembrance days of triumph or tragedy. And each day on a calendar can also have space for us to note, as they come, events which may have an unusual significance only to us; and to remind us of them when they have passed.
The fact is, for all that calendars can give us a repeatable framework for our lives, nonetheless every day is filled with unpredictable moments. Even wonderful events — a wedding, a graduation, a new birth — can be unsettling. That is why, beyond the limits of astronomy or medicine to cure our worries, we can be reassured by the words of the risen Christ to his apostles: “Do not be afraid.”
One striking parallel I find between the worlds of science and faith is the eternal tension between isolation and community. When I am at the telescope looking at a beautiful nebula, or when I am in front of my computer analyzing my data, I am alone. My concentration is entirely on the object before me; I dread the interruption of a visitor to my office or the beep of an incoming email.
And yet I cannot do this work without the community of people who taught me where to point my telescope, indeed who made the telescope for me to point. And I do this work so that I can share it with my colleagues and friends. The joy of discovery is empty if it is not linked to the joy of telling someone else about what I have discovered.
Likewise, every encounter with God is intensely personal and private. And yet I would not know how to find God, much less how to understand that encounter, without the support of my religion. Even people who think they are “finding Jesus on their own,” only know that there is a Jesus to be found because of the community of our forebears who gave us the scriptures.
As a young astronomer I worried that the isolation I experienced in my work meant that astronomy had no relevance to the “real world” of human problems and pain. But when I went to Africa with the US Peace Corps, I found that the Africans themselves were hungry to learn about this universe. It’s a hunger as real as the need for bread; we are human, we cannot live by bread alone.
We are all familiar with the sad irony that so-called “social media” can make us less social, more isolated. The beautiful irony is that an observer isolated and alone on a mountaintop studying the stars is in fact linked to every other human who has looked up at the sky in wonder.
Your support of the Vatican Observatory Foundation helps us build these links among all of us who go alone to the mountaintops, seeking bread for the soul.
And then I wrote… in September our 2021 Calendars become available! What I suspect most people don’t notice is that on the back of every calendar is a little reflection that I write, based on a suggestion — often just a word — from Dr. Brendan Thomson, the volunteer who does all the legwork of putting these incredible calendars together. Over the next three weeks I though I would run the texts of these reflections from the calendars going back to 2016. If I can find earlier calendars I may add to this list!
And since these are meant to encourage people to join our guild and get a calendar, I am not putting them behind the usual firewall…
Why does the Vatican support an astronomical observatory? It’s a common question we get asked, and there are many simple answers.
The Observatory is a way of showing the Church’s support for science. It’s a way of demonstrating that, with a national observatory recognized by other nations, the Vatican City State is indeed its own independent nation. It’s even a way to apologize for the Galileo affair! But all those answers miss the deeper question: why does anyone support astronomy? Why does anyone dedicate his or her life to studying the stars and planets?
There’s no obvious way to turn this knowledge into profit (though astrologers tried to do that in the past, and companies are being formed now that may try to mine resources in space in the future). Astronomy in and of itself provides no obvious route to power or glory. So why does anyone do it?
Each of us has our own reasons, but I suspect the common thread in all astronomers ultimately goes back to the sense of wonder and mystery when we look at the night sky… and even more, the sense of joy that we receive when we suddenly understand some small part of this immense creation. In fact, of all the motivations, joy is the one that comes most powerfully to me. When we display the images of this calendar, we do it to remind ourselves of the joy we feel at contemplating the universe.
C. S. Lewis once described encountering God as being “surprised by joy”… and I believe that this joy of seeing celestial wonders is a sign of the Creator’s presence. That’s why I do astronomy.
That’s why we are all so eager to share this universe with everyone, especially through the work of the Vatican Observatory Foundation. We thank you for helping us share this joy; and we invite you to share it yourselves, among your friends and family.
A few years ago, a couple of cosmologists who styled themselves as atheists attempted to show that there was “no need for God” to start the universe, at the moment popularly known as the Big Bang. They proposed that a quantum fluctuation in the zero-energy vacuum field of the “nothingness” that presumably existed before the Bang occurred could have given rise our our existence.
Their argument, while certain having scientific merit, would have failed any Philosophy 101 class. After all, if one defines “God” as “that which started the Big Bang” and then you define quantum fluctuations as the cause of the Bang, then logically you haven’t disproved God; you’ve proved that God exists, as a quantum fluctuation – whatever they mean by that!
But more seriously, as the late Fr. Bill Stoeger explained in a chapter of our 2009 book, The Heavens Proclaim, the argument fails on a more fundamental level. “Creation out of nothing” is not the same as “creation in a vacuum” since even a vacuum is not “nothing”. As the cosmologists themselves concede, the primordial vacuum contains a zero-point energy; it also contains space, and time, and the laws of physics that allow it to fluctuate… or not.
Furthermore, God’s creation is not something that happened at one time in the distant past. Rather, since God is outside of time, God’s creation occurs continually at all times. From our point of view, every moment, every second, every nanosecond, God is creating. God maintains the existence of the Universe. The famous philosopher Wittgenstein pointed out that nothing can find meaning within itself; only a super-natural God, standing outside of nature, can cause nature to exist and give it meaning. God is not a being; God is Being.
But we Christians realize that God is more than the author of the Big Bang. God so loved this creation that He sent His only Son to become a part of it. In the Incarnation, as St. Athanasius wrote more than 1500 years ago, the universe became “cleansed and quickened”. Thus to study God’s creation, as we do at the Vatican Observatory, is an act of worship both to God who Created and to God who chose to become part of that creation.
Our science reveals a creation that is orderly, understandable, yet infinitely surprising. These features clearly echo the attributes of its Creator. But even more, as the images of these calendars reveal year by year, our science reveals a creation that is also remarkably beautiful.
This article first appeared in The Tablet on 11 September 2010, pp 4-5, following the publication of the book by Stephen Hawking and Leonard Mlodinow, The Grand Design
Cartoon by Paul Thomas, from the Tablet
Stephen Hawking is not the first scientist to declare God obsolete. But his latest findings following his researches into the origins of the universe provoke profound questions about our perceptions of God and the relationship between science and theology.
“Because there is a law such as gravity, the Universe can and will create itself from nothing. Spontaneous creation is the reason there is something rather than nothing, why the Universe exists, why we exist… It is not necessary to invoke God to light the blue touch paper and set the universe going.” Such were the fighting words excerpted in the press from Stephen Hawking’s latest book, The Grand Design, co-authored with Leonard Mlodinow. So no need for God, science has it all sorted.
In the late 1920’s, the Belgian mathematician (and Catholic priest) Georges Lemaître had proposed that the universe was evolving from an initial condition of high energy – what he called a “cosmic seed” and others (notably his friend and rival, Fred Hoyle) dubbed the “Big Bang.” The evidence of astronomy gathered since then has demonstrated pretty convincingly that such a bang did occur. But what was the origin of the initial cosmic seed?
For years, Stephen Hawking has been working on a theory suggesting that quantum fluctuations in a primordial vacuum could provide a setting that would by itself, by chance, produce that initial singularity in space-time. As the cosmologist (and my fellow Jesuit at the Vatican Observatory) Bill Stoeger has explained it, “[James] Hartle and Hawking… showed, by using the concept of imaginary time – by which one treats time exactly like a spatial dimension – and by conceiving that there was no initial 3-dimensional spatial boundary to the universe, that we can in a consistent way obtain from the cosmic wave-function a universe like the one we inhabit.”
Describing it in those terms sounds great in a popular science column, but actually making the maths work out is a different matter. From the sound of the press releases, however, apparently Hawking now feels he’s succeeded.
Hawking is as good as anyone working today when it comes to visualizing, and expressing mathematically, the nature of physics at extreme conditions. For me to judge the physics of his work would be presumptuous, exposing my own ignorance of his field… any more than I would take seriously anything Hawking might have to say about my own research in meteoritics.
Or theology. Suppressing any number of snide comments I could make about the conclusions he draws from his work about God, however (if he hadn’t been able to come up with a theory to start off the universe, would that have caused him to publicly confess God existed after all?), the fact is, Hawking is right. There is no need for a God to start the universe off.
But he’s by no means the first scientist to point this out. When the French mathematician Pierre-Simon Laplace explained his advanced mathematical description of planetary orbits to Napoleon, the emperor interrupted him to ask about the role of God. Laplace is said to have replied, “I have no need for that hypothesis.”
Napoleon’s question was a reference to Isaac Newton’s original work on gravity and orbits. Because there is a law such as gravity, Newton had been able to explain the orbits of the planets. But Newton realized that the interaction of one planet on another might well perturb the stable simplicity of any given planet’s orbit. This gap in his explanation, the fact that the orbits were nonetheless stable, he posited was a demonstration of the action of God. Newton had only just invented differential calculus; Laplace, building with brilliance upon a hundred years’ further development in the field, was able to show that the orbits could be stable without recourse to supernatural intervention.
Newton was a Deist, one who did not see God as personally involved in the lives of individual humans but rather as merely the “prime mover” in Aristotle’s sense, the original source of motion from which all other motions derived. His use of physics as a way of demonstrating the necessity of such a God made a big impact in the 17th and 18th centuries. There was no split between science and religion; rather, religion could be based on the firm certainties of Newton’s laws. To quote Alexander Pope, “God said ‘Let Newton Be’ and all was light.”
But this God of the Gaps is theologically treacherous. The most obvious danger is that (a la Laplace) once the gaps are filled by natural laws themselves, then the “proof” of God’s existence is turned on its head; one instead seems to show that there is no need for God, after all. The Jesuit theologian, Michael Buckley, has argued that precisely this pattern is what gave rise to modern atheism.
A more subtle problem is that such of version of God reduces him to just one force alongside other forces in nature. Rather than supernatural, present in the beginning, outside space and time, God becomes a pagan nature deity, responsible if not for thunder and the growth of crops, then at least the primordial big bang and the growth of the universe.
There is an irony, of course, in Laplace’s dismissal of Newton’s concern. In the two hundred years since his Napoleonic quip, mathematicians have discovered chaos theory and astronomers now understand that planetary orbits can indeed be chaotic. There is good evidence that the early orbits of planets were unstable. Just because the solar system has been relatively quiescent for the past four billion years doesn’t mean it always was that way, or always will be.
Likewise, Hawking’s conception of “spontaneous creation” may someday look as quaint as “spontaneous generation” compared to evolution. Indeed, I would hope so. That’s the sign of a healthy field.
Meanwhile, we may wince at Hawking’s misapplication of the challenge first posed by Newton’s contemporary, Gottfried Liebnitz, in an essay “On the Ultimate Origin of Things.” To ask “why is there something instead of nothing” is very different from asking “how did things get started?” To cite again Fr. Stoeger, “The Creator empowers the physical processes to be what they are. The Creator does not replace them. Creatio ex nihilo is not an answer to the question of temporal origin; Creatio ex nihilo is, instead, about the ultimate ontological origin of reality.” (I am quoting from his chapter in the Vatican Observatory’s 2009 book, The Heavens Proclaim: Astronomy and the Vatican.)
That said, however, Hawking does us an important favor by eliminating such an image of God. The “god” that Stephen Hawking doesn’t believe in is one I don’t believe in either. God is not a force to be invoked to swell a progress, start a scene or two, and fill the momentary gaps in our knowledge.
God is the reason why existence itself exists. God is the reason why space and time and the laws of nature can be present for the forces to operate that Stephen Hawking is talking about.
What’s more, I believe in such a God not because of the absence of any other explanation for the origin of the universe, but because of the person of Jesus Christ — in history, in scripture, and in my own personal life of prayer. And even more strongly, I have faith in this God not merely because the universe exists, but because it is beautiful and fun to play in… that play we call science.
Professor Jim Peebles is the 2019 Nobel Laureate of Physics. I have had the pleasure to meet him and hear him give talks in the field of Cosmology, or the study of the shape, history, and future of the universe.
In a recent talk Professor Peebles made an interesting comment about the study of science in general. He asserted that “nature operates by rules we can discover.” He went on to say that there was never a guarantee that it would have turned out to be that way.
Scientists do seem to work with a kind of blind faith that the universe is knowable, and without necessarily realizing how exciting it is that so much of science is that way.
After all, we know enough physics now to launch rockets that explore space. At the same time, there is a lot of physics that we still do not fully understand, such as how gravity works.
When I give a talk I see that this weakness often seems to surprise people. Gravity is the easiest force of nature for the public to understand, while electromagnetism, and the strong and weak nuclear forces, are more abstract concepts.
The person who has come the closest to understanding gravity is Professor Albert Einstein. Einstein’s model is formalized in his General Theory of Relativity, “GR.”
Einstein’s view of gravity is that objects can propagate ripples in spacetime, analogous to ripples on the surface of water. The most recent test of GR is the first detection of these “gravitational waves.” Although GR may not be sufficient ultimately to understand all of gravity, we appear to be on the right path.
In sum, perhaps the fact that we can investigate nature and learn so many of its secrets is a kind of gift to us? What do you think?
And then I wrote… Finishing up my string of articles for the International Year of Astronomy, this paper was one that I never got to give. I was supposed to fly from London to Italy for a conference on the celebration of Galileo’s telescope, to be held in his old home town of Padua, but the day my flight was scheduled to leave Gatwick the airport was shut down due to snow!
As so many of the presentations at this conference have confirmed, Galileo’s discoveries with the telescope, epitomized by his discovery of satellites orbiting Jupiter, revolutionized astronomy. They also revolutionized our view of the universe, what has been come to be called our scientific “cosmology.” And in the process, they gave a new emphasis to the whole question of other worlds and other civilizations.
To appreciate the impact that Galileo’s observations had on our cosmic sense of ourselves and our place in the universe, it is important to begin with an accurate understanding of the old version that his observations overthrew. It is wrong to think that humanity’s understanding of the universe was a simple Earth-centered view, that there were no other competing models in the ancient world, or that there was no speculation about other worlds and other civilizations before Galileo.
And, indeed, as we know, Galileo did not propose a new model of the universe; that honor, of course, goes to Copernicus. Nor did he improve it, as Kepler did. Nor did he put it on a deeper physical basis, the way Newton did. Nor did his observations even demonstrate that it was true, in a mathematical sense, since certainly the Tycho Brahe model fit Galileo’s data as well as the Copernican model did. Nonetheless, Galileo’s observations and publications were crucial, indeed a pivotal event, in all of these developments. To see why, it is necessary to see the nature and the role of cosmologies in human culture.
C. S. Lewis (Lewis, 1964) has described the medieval view of the universe as “The Discarded Image.” It was…
This post comes from a “Science in the Bluegrass” column I wrote for The Record, the newspaper of the Archdiocese of Louisville, Kentucky. That column in turn came from a series of posts I wrote for Sacred Space Astronomy in early 2018, so if you have been reading this blog for a while, you will recognize the general idea here.
Extraterrestrials! They are an idea from science whose impact on popular culture has been huge. Think of those big movie franchises that involve beings from other worlds: Marvel, Star Wars, Star Trek, and more.
Extraterrestrials have not always been popular. Aristotle, the great Greek philosopher from before Christ, reasoned that Earth is the only world that exists. No other worlds. No extraterrestrials.
Aristotle influenced many Greco-Roman, Jewish, Christian, and Islamic thinkers. However, in 1277, the bishop of Paris officially condemned Aristotle’s idea that Earth could be the only world. An omnipotent God, the bishop said, could make any number of worlds. Different medieval thinkers, most of them Catholic clergy, got creative imagining God’s other worlds and their extraterrestrial inhabitants. One cardinal, Nicolas of Cusa, wrote about how it would be harder to converse with extraterrestrials than with dogs. After all, we have things in common with dogs, like mouths and voices. We might have nothing in common with extraterrestrials.
A Google image search on “smart dog” yields these pictures. So are any of these dogs smart enough to talk with you?
The extraterrestrials idea truly caught fire after 1543, when Copernicus proposed that Earth circles the sun, and Mars, Jupiter, etc. do, too. Aristotle had said the sun circled Earth, while Mars and Jupiter were wandering lights in the sky that had less in common with Earth than a flame had with a rock. Under Copernicus’s revolutionary idea, those planets had something in common with Earth: circling the sun.
The invention of the telescope and developments in physics soon showed that planets have moons, rotate, and have gravity, like Earth. Astronomers concluded that planets were other “Earths”. And, that they must have intelligent life. Why would Earth be unique among worlds? Scientists at that time thought that life arose spontaneously from matter (another idea from Aristotle), so why wouldn’t life be everywhere?
Scientists figured stars were other suns, with inhabited planets circling them, too. A prominent early nineteenth century science writer, Thomas Dick, estimated 22 trillion intelligent beings in our solar system alone; 62 septillion in the universe overall. At that century’s end, some astronomers claimed to have detected evidence of an advanced civilization on Mars. The New York Times and the Wall Street Journal published that big news. Edgar Rice Burroughs and H. G. Wells wrote novels about Martians. Extraterrestrials became big in popular culture.
But since then, scientists have learned that life does not spontaneously generate from non-living matter. Our telescopes have improved. Our robotic probes have traversed the solar system. Our radio telescopes have scanned for interstellar radio chatter for six decades. Over the past thirty years our ability to detect advanced civilizations, even in other galaxies, has grown dramatically. But we have detected nothing.
Meanwhile, we have learned that stars and planetary systems are wildly diverse; few solar systems look like ours. We have learned that there is no intelligent life, and maybe no life at all, on Mars or any other solar system planet. We have no idea how life arises. We know only that Earth has it.
Earth is unique in our solar system. The likelihood is growing that Earth is pretty unusual overall. The extraterrestrial-filled universes of Marvel, Star Wars, and Star Trek might have seemed plausible back in the 60’s and 70’s when they were created; they don’t now. Just as in the days of Copernicus, we stand in the middle of a great revolution in our understanding of the universe.
Is it vindication at last? The New York Times has recently reported that a supposedly canceled Pentagon project to investigate strange aerial phenomena is still showing a pulse. The clandestine effort, originally known as the Advanced Aerospace Threat Identification Program, was said to have ended in 2012. But, apparently, it’s still doing its thing under the auspices of the Office of Naval Intelligence.
So, where there’s smoke, there’s fire, right? If the feds are still forking over tax dollars to delve into odd goings-on in the sky, it must be because they’ve got convincing evidence for extraterrestrial visitors. At least that’s the hope of the 100 million Americans who seem willing to swear on the Good Book that UFOs are, at least in some cases, alien craft.
But hang on a minute. Before you order that on-line course in Klingonese, consider what might really be going on here. When the Times first reported on this subject in 2017, it was talking about some puzzling videos taken by Navy fighter pilots over the Pacific. They showed unidentified objects ahead of the jets, objects that seemed to maneuver in bizarre ways. So perhaps the controversial program is simply an additional effort to finally nail down what these objects are. After all, the military has always wanted to know about anything that can fly, and for obvious reasons.
That’s the most straightforward explanation for why the Navy has continued the Pentagon program. It’s also what they’ve said.
But isn’t it possible that what’s really going on here is not an investigation into unknown aircraft or drones, but a distraction to keep us from a more disturbing truth – that UFOs aren’t enemy flying machines, but alien flying machines? Maybe the government doesn’t want to admit this, because they figure we’d all go nuts.
Mind you, it’s hardly clear why extraterrestrials would hie themselves many trillions of miles through the dangerous voids of space simply to pirouette above our heads and occasionally play cat-and-mouse with the Navy. But – full disclosure – we really don’t know what the aliens find interesting to do. Maybe they have their reasons.
This story has an additional fillip. It speaks of “retrieved materials” that are “not made on this Earth.” This claim seems both surprising and suspect. The pilots didn’t report picking up pieces of spacecraft or strange metal alloys (at least not publicly), so it’s unclear where these “materials” were found. In addition, unless an artifact is clearly highly complex – like a Reptilian cell phone – how can you know that it’s not from this planet? This is a case where seeing might be believing, but no one has let us see anything. Which is convenient, if less than fully convincing.
There’s an intriguing facet of this story that I think helps point to the truth. Not only do the extraterrestrials (if that’s what they are) spend time teasing our Top Guns, they also seem to hang out above our military bases. This is an aspect of their uninvited presence which, according to the Times article, has especially disturbed Senator Marco Rubio.
Well, if you’re a sci-fi fan, you’re well acquainted with the idea that hostile aliens need to pay attention to our armament. After all, it might be used to drive them off. And perhaps it’s what’s lured them to Earth in the first place. They’ve come as saviors from on high, keen to separate us from our own weapons of mass destruction. That would, at least, be a reasonable explanation for their apparent interest in our combat capabilities.
But truth be told, it’s totally unreasonable. If the aliens can actually come here – whatever their motivation – then they have technology that’s enormously beyond our own. Comparing their weaponry to ours would be like comparing the U.S. Air Force to an Australopithecus raiding party. Put another way, do you honestly think Captain Picard would ever spend time checking out piles of slingshots or pikes on some primitive planet because, after all, those are state-of-the-art weapons for the local residents?
If whatever it is that the Navy is investigating is real, it’s supposed interest in our military suggests Russian aircraft, Chinese drones, or something else terrestrial. It’s actually an argument against visitors from another star system.
Humans have always been tempted to ascribe strange phenomena to the workings of superhuman beings, much as the Greeks argued that lightning bolts were javelin tosses by Zeus. But science demands that any hypothesis be supported by detailed, repeatable, and impartial observations. Those are lacking here.
The Office of Naval Intelligence will supposedly make regular reports on at least some of their findings. That sort of disclosure sounds as if it would be good news for those who, like Fox Mulder, “want to believe.” But in fact, it might actually work the other way. Disclosure could rob the believers of their best piece of evidence – which is to say, a dearth of good evidence.
The Nobel Prize in Physics went to Swiss Michel Mayor and Didier Queloz for their work on exoplanets. What are the implications at the theological level?
December 26, 2019 in science, christianity, theology
(Anne-Sylvie Sprenger) The question is simple: does the existence of exoplanets, i.e. planets outside our solar system, necessarily imply the existence of extraterrestrial life forms? The answer is not quite as simple. Certainly the works of the Swiss Michel Mayor and Didier Queloz, awarded the Nobel Prize in physics, have disrupted research in this field. We take stock of the situation with Jacques Arnould, in charge of ethics at the National Center for Space Studies and author of numerous works at the intersection of sciences and theology, including Turbulences dans l’ivers: Dieu, les extraterrestres et nous (“Turbulences in the ‘universe: God, extraterrestrials and us ”, ed. Albin Michel).
How do you evaluate the recognition conferred today on physicists Michel Mayor and Didier Queloz?
First of all, let me say: it was time! We must not forget that the discovery by Michel Mayor and Didier Queloz of the first planet outside our solar system dates back to 6 October 1995! A wait of twenty-four years before being rewarded for one of the greatest achievements of astronomy of the late 20th century: definitely, patience is one of the main qualities of the astronomer!
How has scientific research developed on the question of the existence or not of extraterrestrial life forms?
The launch of Sputnik in 1957 and the beginning of the space age obviously influenced the work of scientists in the search for extraterrestrial life forms. To the philosophical and theological conjectures – the first traces of which date back to the second millennium before our era – and to the observations conducted with the aid of terrestrial telescopes, the exploration missions of the Moon, Mars and the solar system have in fact been added. Thus were born the disciplines of exobiology and astrobiology that articulate disciplines that until then had not sought or had not had the opportunity to collaborate: astrophysics and astronomy, physics of atmospheres and chemistry of primitive life forms, study of origins of life and its evolutions, etc. Even the humanities are invited to join this singular “conspiracy”!
And where are the progress of these research works today?
The sector is making great strides: to the discovery of exoplanets inaugurated by Mayor and Queloz [more than 4,000 have been registered to date, ed.] Are added the works carried out on the nearest planets; think of the feats of robots on the surface of the planet Mars or the landing of the Philea space probe on the surface of comet Tchouri: so many opportunities to go hunting for possible “elementary particles of life”! On Earth, researchers hunt for the slightest traces of life in the most extreme conditions: frozen lakes, sea beds, volcanic areas; they even “created” a new category of living organisms: extremophiles, in other words organisms that “go crazy” for conditions usually considered prohibitive. So many opportunities, as we can well understand, to ask ourselves about the conditions of emergency and evolution of living organisms, about the characteristics that an environment, a planet must possess in order to be considered habitable. However, despite all our efforts, we have not yet found life forms anywhere other than Earth …
You wrote “Turbulences dans l’ivers, Dieu les extraterrestres et nous” (“Turbulences in the universe: God, extraterrestrials and us”). The Bible, however, never seems to address the question …
The hypothesis of an extraterrestrial life is not the only question that is not addressed by the Bible! We do not even read about the discovery of the New World, antibiotics or television … Try to find answers to all the questions in the sacred text, to all the problems, theoretical or practical, that we human beings can pose would be to give in to one of the most serious reading defects that exist: concordism. By this I mean the tendency, the will to place the Bible at our level, at our service, to reassure us or secure our power.
Doesn’t science contradict biblical texts?
The development of the sciences, especially since the 17th century, has in some way disrupted religious beliefs, especially Christian ones. Our vision of the world, of life, of the human being has been profoundly modified by the work of scientists such as Galileo Galilei, Johannes Kepler, Charles Darwin, Albert Einstein and many others, up to Mayor and Queloz! But why be afraid? Although the Bible does not directly address the issue of extraterrestrial life, it does not lack resources to invite us to reconsider our way of positioning ourselves at the center of the universe. Let’s start by reading again all the accounts of creation, not only those in the book of Genesis, but also those present in the book of Psalms, in the book of Job: confessing the creative work of God does not mean sticking to them, closing oneself in the quasi-liturgical calendar of the first. chapter of Genesis or having to defend a rigid anthropocentrism. We broaden our horizons, we discover the cosmic dimension of certain Psalms or certain Christological hymns. Of course, it is not a question of “little green men”, but rather of looking beyond our horizon, of opening ourselves to this newness that God has never stopped promising to his chosen ones.
More precisely, what are the theological implications of the results of Mayor and Queloz’s work?
So far we have not found living organisms outside our planet. Of course, the chances of finding them have increased, particularly with the discovery of exoplanets; but that does not mean that we will definitely do a “tombola”! We must realize that the answer to the question about extraterrestrial life is inevitably unbalanced: only the affirmation of its existence is possible; that of its non-existence is impossible because we will never be able to inspect every corner of our universe.
And from the theologian’s point of view?
The Christian theologian can ask himself about the consequences of the existence of forms of life and even of intelligence in another place other than the Earth: he can lead what scientists call a thought experience. In other words, how to think, how to say and explain the Christian faith, in the event that God created other living beings, other intelligent beings. We must not be afraid of such a possibility: in the 13th century the bishop of Paris rightly explained that we cannot place limits on the divine ability and will to create.
Of course, the difficulties are not lacking: from the 17th century onwards that of the possibility of an Incarnation and a Redemption in another place other than the Earth has divided the community of theologians; even today this prospect can appear dizzying. Let us consider it at least as an invitation to (re) discover the cosmic dimension of our Christology.
Can you be a Christian and believe in extraterrestrials?
I like this question, because it invites us not to mix our fashions, our ways or our reasons for believing. Extraterrestrials belong to those subjects of faith that seem to impose themselves on us: by dint of looking into our telescopes we cannot escape the question of their existence and we are forced to decide whether to believe it or not, waiting to discover traces of them or to receive a visit from them. . But we can also decide not to deal with it! Being a Christian, believing in God is something different: it is a vital question. The meeting of Jesus and Martha at the moment of Lazarus’s death is not an encounter of the third type, that is, between an earthly and an extraterrestrial. The question that Jesus asks Martha is essential: “Do you believe in the resurrection? You believe in me?”. And Marta commits her whole heart, her whole mind to it. Such an encounter, such a faith are not extraterrestrials: they are extraordinary! (from ProtestInfo; transl. it. G. M. Schmitt)