Visibility of the Heavens in Ancient Times
Artificial nighttime lighting (ANL) likely dates back to Adam and Eve. The archaeological record testifies that Homo sapiens sapiens (modern humans) always had control over fire. Therefore, nighttime camp and hearth fires would have been common. The earliest written records mention the widespread use of candles and oil lamps.

These early forms of ANL were intermittent, rarely intended to provide illumination for more than a few hours, and illumination levels were low, typically below that of a 40-watt incandescent bulb. The illuminated areas were small, too, usually only about 10 square meters. For people of the Roman Empire and earlier, a short walk or a few hours wait would be sufficient to escape any ANL interference with views of the nighttime sky. 

When God told Abraham to “look up at the sky and count the stars—if indeed you can count them,”¹ the night sky on a moonless night was so dark that any human adult with good eyes could see ~15,000 stars. Abraham saw the Milky Way and dozens of nebulae, an awe-inspiring sight. His contemporaries’ ability to determine the great distances to the Moon and the Sun and their inability to measure distances to the stars spoke to them of the vastness of the starry realm.

With the invention of the telescope in 1608, humans could see, for the first time, hundreds of thousands of stars. By the late 1600s, millions of stars had become visible.    

Decreasing Visibility of the Heavens
The industrial revolution of the 1800s and especially the technological revolution that followed the end of World War II had a blinding effect. With gas lighting replacing oil lamps in the 1800s, city streets remained illuminated all night long. By the end of the 1800s, incandescent electric bulbs replaced gas lighting. In the 1900s, incandescent bulbs gave way to mercury vapor lamps, which subsequently gave way to low-pressure sodium lamps. Now, LED lighting is replacing mercury and sodium lamps.

Each technological advance in ANL has made nighttime lighting much brighter, more pervasive, and much less expensive. Thus, since 1900, ANL has been increasing exponentially, and the rise in ANL has been especially steep since 2000.

Sadly, the twenty-first-century rise of ANL has brought with it serious health challenges and ecological consequences.² At the same time, it has drastically reduced the visibility of the heavens for the majority of the world’s population.

For the first time in human history, most people live in large metropolitan areas. In such places, ANL is so intense that when they look up at the night sky people see fewer than 50 stars! I’ve been in some Asian cities where, on a “clear” night, not even the brighter planets were visible, let alone any stars. In some of these same cities, the combination of light and air pollution makes seeing the Moon impossible, unless it is at least 15 degrees above the horizon. So, for hundreds of millions of people, the heavens declare nothing about the glory and righteousness of God. For them, the magnificent heavenly objects remain totally invisible.  

Decreasing Effectiveness of Telescopes
Abraham’s generation did not need telescopes. Our generation does. The availability of telescopes helps compensate for what we cannot see with our unaided eyes. With a good pair of binoculars, we can travel to the countryside to see all that Abraham could see. We can visit the NASA and ESO websites and marvel at images taken by the Hubble Space Telescope (HST), the Very Large Telescope array, and now the James Webb Space Telescope (JWST).

However, civilization and technology are now threatening the capability of telescopes to see the heavens clearly. How? Satellites now number in the tens of thousands. Within a decade, proposed satellite constellations could raise the number of satellites orbiting Earth as high as a hundred thousand, even a quarter of a million or more.

Satellites orbiting Earth reflect sunlight. They create streaks of light across images of the night sky (see figure 1). Especially in the case of long-exposure telescopic images, dozens of satellite streaks brighter than the natural objects astronomers are attempting to observe and measure severely degrade the quality of the research results (see figure 2).

Not only ground-based telescope images are being marred by satellite streaks. Satellites leave bright streaks across images taken by the HST, as well. In 2021, 5.9% of HST images exposed for just 11 minutes were streaked by satellites.³ Deep HST images take hours. The percentage of images marred by satellite streaks rises proportionally with exposure time. You can imagine researchers’ frustration.

Figure 1: Light Streak from an Artificial Satellite above the Very Large Telescope
Credit: ESO

Figure 2: Astronomical Image Marred by Satellite Trails
Credit: Victoria Girgis/Lowell Observatory  

As seriously as optical wavelength telescopes are impacted by ANL and Earth-orbiting satellites, radio telescopes are impacted to a far greater degree. Radio interference from ground-based and satellite transmissions is both strong and pervasive, and it’s only growing stronger and more pervasive. I’ve written recently⁴ about how radio interference seriously limits long-wavelength radio astronomy, and I must add that it also seriously limits short-wavelength radio astronomy.

The research on which I based my doctoral thesis is no longer feasible. For the detection sensitivity required, I used broadband receivers at five different centimeter wavelengths. Today, these bandwidths are saturated by radio interference. Radio astronomy at these wavelengths is now confined to a few narrow “protected” bandwidths.   

ANL Increase by Satellites
In 2020, a team of astronomers calculated the degree of illumination from Earth-orbiting satellites at the zenith (directly above any point on Earth’s surface) at midnight. The skyglow amounted to 20 microcandelas per square meter.⁵ (1 candela expresses the light emitted by a candle of specific size and composition.) This level of illumination already degrades astronomers’ observations. 

The megaconstellation satellite systems proposed for launch during the next 15 years will increase midnight zenith illumination by more than ten times. It may even become noticeable to people living in rural areas.    

Dark Sky Refuges
The International Astronomical Union has appealed to the United Nations Committee on the Peaceful Uses of Outer Space to protect the night sky’s darkness for the sake of future advances in astronomy. While astronomers cannot stop the launch of satellite constellations, the best they can hope for is that corporations manufacturing satellites will make them less reflective. 

Radio astronomers feel especially hopeless. The proposed satellite arrays will be transmitting powerful signals across most of the radio spectrum. 

The one remaining “radio quiet” location in the solar system is the far side of the Moon during the lunar night. However, even this site is under threat. In the next decade or so, the Moon will become the target of hundreds of orbiters and landers. These orbiters and landers could spoil radio astronomy’s last remaining refuge.⁶

At a conference called Astronomy from the Moon: The Next Decades, held at the Royal Society of London, astronomers raised the alarm. They called on governments to establish international treaties that would protect the Moon’s far side. In particular, they called for the shelving of plans to install a lunar satellite navigation system. They asked that strict rules be applied to any satellite or lander operating on the Moon’s far side. 

More than 250 lunar missions are scheduled for launch during the next decade. The time window to draft appropriate treaties and acquire necessary signatures is small and rapidly shrinking.

Meanwhile, optical and infrared astronomy research is also being squeezed out. The remaining refuge for these types of observations is the Lagrange 2 point (L2) along Earth’s orbit. This point is about a million miles away from Earth, where the JWST has been operating for the past year. The European Space Agency’s Euclid Space Telescope is on its way to join the JWST in L2.

To place telescopes at the L2 site is not inexpensive. The JWST, for example, cost $10 billion. Furthermore, the L2 site is subject to meteorite and micrometeorite impacts, and L2 is too far away for repair or upgrade missions.   

What’s at Stake?
Increasing ANL threatens more serious consequences than interference with the astronomy research I’m passionate about. It will bring more serious health and ecological consequences than those we’re already experiencing. For one example, the Bible speaks of a time when people’s love will “grow cold.”⁷ It’s easy to see how ANL may be partly to blame. 

ANL reduces both the duration and quality of sleep.⁸ A recent study shows that sleep loss exacerbates depression and reduces expression of altruism.⁹ Altruism would likely be further reduced and depression further increased as people lose the ability to see the beauty and wonder of God as expressed in the heavens. Much more than astronomical research is at stake.

What Can Be Done?
Technological advances have made ANL, the Internet, and global positioning systems remarkably accessible. The low cost of these amenities tempts humans everywhere to expand their usage. However, the time has come to address significant questions: 

1. Can we limit ANL to places where it’s essential for safety? 
2. Can we move ANL wavelengths toward the red end of the spectrum, where its effects are less harmful?
3. Can we develop new technology so that we can get by with many fewer satellites?
4. Can we make satellites less reflective, less “noisy,” and place them in lower orbits? 
5. Can we design satellites to de-orbit once they cease useful operation? 
6. Can we develop and implement a system for the retrieval and safe disposal of obsolete satellites and space litter? 

I believe we can do all these things and more, as well, to help restore access to the revelation of God’s glory and righteousness in the heavens. Personally, I love to show people the gorgeous images being released by space telescopes and explain what they tell us about our Creator.

Although I may seem to be bashing technology, I greatly value one particular smartphone app. When the phone is aimed up at the night sky, it identifies astronomical objects that can be detected there. A good pair of binoculars (e.g., 7 x 50 or 10 x 50) can be linked to the smartphone for enhanced viewing of the planets, moons, stars, and nebulae. 

The sense of wonder that comes from observing and pondering the heavens nearly always leads to in-depth conversation about the One who brought them—and us—into existence.    

Endnotes

1. Genesis 15:5.
2. Hugh Ross, “Is Artificial Nighttime Lighting Too Much of a Good Thing?” Today’s New Reason to Believe (blog), Reasons to Believe (October 17, 2022).
3. Sandor Kruk et al., “The Impact of Satellite Trails on Hubble Space Telescope Observations,” Nature Astronomy 7 (March 2, 2023): 262–268, doi:10.1038/s41550-023-01903-3.
4. Hugh Ross, “LuSEE: Boldly Going Where No One Has Gone Before,” Today’s New Reason to Believe (blog), Reasons to Believe (July 24, 2023).
5. M. Kocifaj et al., “The Proliferation of Space Objects Is a Rapidly Increasing Source of Artificial Night Sky Brightness,” Monthly Notices of the Royal Astronomical Society: Letters 504, no. 1 (June 2021): L40–L44, doi:10.1093/mnras/slab030.
6. Davide Castelvecchi, “Are Telescopes on the Moon Doomed before They’ve Even Been Built?” Nature 615 (March 16, 2023): 383–384, doi:10.1038/d41586-023-00635-8.
7. Matthew 24:12.
8. Maja Grubisic et al., “Light Pollution, Circadian Photoreception, and Melatonin in Vertebrates,” Sustainability 11, no. 22 (September 14, 2019): id. 6400, doi:10.3390/su11226400.
9. Eti Ben Simon et al., “Sleep Loss Leads to the Withdrawal of Human Helping Across Individuals, Groups, and Large-Scale Societies,” PLOS Biology 20, no. 8 (August 23, 2022): id. e3001733, doi:10.1371/journal.pbio.3001733.

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For example, when astronomers observe the Sun, they don’t see it as it is now, but what it was about 8 minutes ago since it took light from the Sun 8 minutes to travel to Earth. Similarly, when astronomers observe the Andromeda Galaxy, they see it as it was 2.5 million years ago since it is at a distance of 2.5 million light years.

Since the universe is only 13.8 billion years old, the most distant observable objects are 13.8 billion light years away. However, the universe has been continuously expanding ever since the cosmic creation event. Hence, the universe that exists today is much larger than the universe astronomers can detect through their telescopes. Based on the measured cosmic expansion rate, astronomers have determined that the presently existing universe is at least 93 billion light-years across.

At RTB, our astrophysicists study the universe’s mass, size, and designs, revealing just how immense and finely tuned it truly is. Let’s explore what science can observe and what Scripture helps us understand. Together, they reveal not only the scale of the cosmos in miles and light-years, but also the intentionality behind it. They reveal that the universe didn’t happen by chance. Its precisely fine-tuned mass, size, and designs remind us of God’s magnitude and power—and of how much more exists beyond what our minds can comprehend.

What Is the Size of the Universe?

To say that the universe for most people is unimaginably big is no exaggeration. Nevertheless, the universe’s size can be visualized. The universe astronomers can see through their telescopes contains about 2 trillion galaxies. Galaxies on average contain about 50 billion stars. That adds up to a hundred billion trillion stars in the observable universe.

How big are the stars? They range in size from 6 miles to a billion miles in diameter. The Sun is a medium-sized star with a diameter of 865,000 miles. One way to visualize the Sun’s size is that one could pack 1.3 million Earths inside the Sun. One way to visualize the largest stars is that one could pack 1.5 billion Suns inside the largest star!

We live in a large spiral galaxy. Our galaxy’s spiral disk contains an estimated 200 billion stars. Our galaxy is orbited by 152 globular clusters. The smallest such globular cluster contains about 50,000 stars. The largest contains about 10 million stars. The giant galaxy M87 in the nearby Virgo Cluster of galaxies has 17,000 globular clusters orbiting it. The largest known galaxy is a thousand times more massive than our Milky Way Galaxy, which weighs 1.2 trillion times the Sun’s mass.

How far apart are the stars from one another? If one were to scale our Sun down to the size of a grapefruit and place it at Terminal 1 of the Los Angeles International Airport, the nearest other grapefruit (star) would be in Peru.

How big is the universe? The observable universe contains a hundred billion trillion stars where the stars are separated from one another by an average of about 25 trillion miles. See this video for a visual treat showing how big is the universe.

And yet, what we see is not all there is. The stuff we see through our telescopes, the stars, planets, nebulae, and galaxies, comprises just 0.27% of the universe. Most of the universe, the other 99.73%, is made up of dark stuff.

The total quantity of stuff in the universe, as incredibly massive and big as it is, cannot be any smaller or any larger for life to possibly exist in the universe. Make the universe the tiniest bit smaller, no elements heavier than helium would exist. Make the universe the tiniest bit bigger, no elements lighter than iron would exist. In both cases the universe would contain no carbon, no nitrogen, and no oxygen and physical life would be impossible.

Evidently, the Creator of the universe did not think it too costly to create a vast universe and carefully and exquisitely fine-tune it for 13.8 billion years so that human beings could live and thrive on a beautifully designed planet. How great is the Creator’s love for us that we see manifested in the size, mass, and designs of the universe!

How Do We Measure the Size of the Universe?

We measure the universe through light emitted by its galaxies, stars, nebulae, gas, and dust.

Astronomers trace light across the ages, following its path through space to learn how the universe has changed over time.

They use methods with names that sound almost poetic—like parallax, redshift, and standard candles—but each one is rooted in careful measurement. Together, these tools help translate the majesty of creation into data we can study and understand.

Every beam of light carries information about where it came from and what it’s passed through, a record of the universe’s history written in photons.

And the more carefully we measure, the more awe we uncover. Every beam of light reveals the physical state of the cosmic object that emitted it and the precise values of the laws and constants of physics at that cosmic site and that cosmic time. Every light beam reflects the faithfulness of the Creator.

Science calls it testable, measurable, and reliable. Faith calls it design.

The Expansion of the Universe: The Sky That’s Still Stretching

We’ve learned something else from that ancient light: the universe isn’t static.

It’s alive with motion and growth—unfolding and stretching toward horizons we have yet to see.
From the first spark of creation, space itself has been expanding.

Every galaxy became a traveler, drifting outward on a tide that has never ceased.

Astronomers can see it even now: galaxies slipping away in every direction, their light stretched thin into longer, redder wavelengths, like a song deepening as it echoes through time.From the beginning, God designed a universe that expands, a scientific concept consistent with Scripture’s description of him “stretching out the heavens.”

And yet, the same God who sent the galaxies expanding away from one another also holds them fast. Gravity gathers stars into clusters, planets into orbits, and atoms into being. As physicists study these phenomena, they see incredible cosmic fine-tuning, a precise balance of forces that lets stars burn, atoms bond, and galaxies hold their form.

Physics reveals a sophisticated dance between forces that hold them together and ones that pull them apart. The expanding universe is governed not by chaos, but care.

Distant galaxies race away from us faster than nearby galaxies. This observed phenomenon is the predicted outcome of the entire universe undergoing a nearly constant rate of expansion. Just like dots on an expanding balloon that are farther apart than dots that are closer together appear to move away from one another at a faster rate, so too the greater a galaxy’s distance from us the faster it moves away from us.

Astronomers call it continuous expansion.

Scripture says the Lord “stretches out the heavens like a canopy, and spreads them out like a tent to live in” (Isaiah 40:22).

Different words. Same truth.

Astronomers’ measurements of the cosmic expansion rate reveal that the expansion rate is gradually accelerating. This acceleration implies that some time in the future the most distant galaxies will be moving away from us at speeds greater than the velocity of light. When that happens, these galaxies will cease to be visible to us. One day, the galaxies’ light will drift beyond our sight, not because the light has died, but because the space between has stretched too wide for it to reach us.

Is the Universe Infinite in Size?

Stay under the stars for a while, and you’ll start to wonder—does this ever end?

Astronomers have mapped the observable universe, limited by how far light can travel since the beginning.

Beyond that? We can only imagine. 

Some have even proposed that our universe may be one of many, a multiverse, a vast ensemble of realities beyond our reach.

Even if physical realms exist beyond the observable universe, physicists expect them to follow the same physical laws, constants, and patterns as the universe we can see. This idea—known as the cosmological principle—assumes that the universe is uniform and governed by the same laws everywhere, not just in our corner of the cosmos. Indeed, everywhere we can make measurements, we see that the laws and constants of physics measure to be exactly the same as they are on Earth.

That consistency points to the reliability and order built into creation by its Designer.

The size of the observable universe is something we can accurately measure. The fine-tuned features of the universe reveal its order, wonder, and at least eleven distinct purposes or reasons why the universe is the way it is. 

How Big Is the Universe?

The size of the universe reminds us just how small we are and how immense the One who designed it must be.

Isaiah wrote that God measures the heavens “with the breadth of his hand” (Isaiah 40:12). What ancient Scripture expresses, modern astronomy confirms scientifically: the heavens are vast, measurable but beyond our ability to comprehend, and governed by precise physical laws.

Every advance in observation, each new telescope, each new image of distant galaxies doesn’t diminish mystery, it deepens it. The more we discover, the more evidence we see of order, stability, and fine-tuning throughout all of creation.

How big is the universe, really?

Big enough to silence pride.
Small enough to rest within the reach and control of its Creator.

The story the 2 trillion galaxies and a hundred billion trillion stars are telling isn’t about how far they extend, but how faithfully God reigns.

The Shape of the Universe

Astronomers have measured the universe’s size, age, and expansion with remarkable precision, but its overall shape remains one of cosmology’s most fascinating questions.

Current evidence from satellite missions such as WMAP and Planck suggests that the universe is flat on large scales. In a flat universe, light travels in straight lines rather than curving back on itself. This means that, within the portion of the cosmos we can observe, parallel lines would never meet.

However, beyond the limits of our observation, the question is still open.

Some scientists have theorized that the universe is curved like a sphere—a “closed” model—where light could, in theory, circle all the way around and return from behind its starting point, like a traveler who leaves home and arrives again from the opposite direction.

Others suggest it may be that its shape is like a saddle, an “open” model bending ever outward, a universe that never meets itself again.

While we don’t yet have enough data to determine the universe’s exact geometry, the evidence we do have shows extraordinary consistency. The same fine-tuning that governs its forces and constants appears to extend to its shape. The order we observe in the universe’s geometry reflects the character of the One who established its laws—a God of balance, harmony, and design.

How Large Is the Universe?

When astronomers talk about how large the universe is, those discussions not only describe its scale but must also include the remarkable reliability of how the universe behaves. Immensity and intricacy coexist; the same physics that govern entire galaxies also govern the atoms in our own bodies.

Isaiah 40:26 and Psalm 147:4 state that God has given a name to every star and knows the name of every star. If he knows the name of every star, he certainly knows our name. If he cares for every star, he certainly must care immensely more for every human being. As Jesus said, “Indeed, the very hairs of your head are all numbered” (Luke 12:7). The same God who governs galaxies also knows every detail of the world and of each life within it.

Does the Universe End?

Astronomers have long studied what the distant future of the universe might hold. One of the most widely accepted scientific models is known as the Big Freeze or the Heat Death of the Universe. In such a universe, hot bodies will get colder and cold bodies will get warmer. Eventually, every body, every speck of dust, every gas molecule and every atom will attain the identical temperature. When that happens heat will cease to flow in the universe. Work will become impossible. Life will become impossible.

Scripture, however, reveals that what looks like a depressing, hopeless ending is really a transition. God is using the present physics of the universe to eradicate sin and evil. The apostle John describes a future “new heaven and a new earth” (Revelation 21:1), and Paul wrote that what is sown perishable will be raised imperishable (1 Corinthians 15:42–44). In other words, creation is not destined for extinction but for renewal. The moment God completely eradicates evil and finishes his work of redeeming willing humans from their sin, he will replace the universe with the new creation, a realm with radically different physics and different dimensions, a realm where God will reward his followers with blessing far beyond what they can imagine (1 Corinthians 2:9).

The same God who stretched out the heavens will bring his creation to completion, demonstrating that nothing, not even the cosmos itself, lies beyond his redemptive plan.

Bigger Than the Universe: The God Who Cannot Be Contained

If creation stretches across billions of years, trillions of galaxies, and miles beyond measure, then the question remains: What could possibly be bigger than the universe?

We can see the stage.
But who wrote the play?
Who drew back the curtain of space and time?

No constellation of laws or particles can explain that first spark.
Everything within the universe depends on something beyond it.
Even skeptical scientists agree on this much: whatever ignited our universe can’t be part of it. It must exist outside our space and time altogether.

Scripture says it plainly: “By faith we understand that the universe was formed at God’s command, so that what is seen was not made out of what was visible” (Hebrews 11:3).

Because God is beyond, he isn’t bound by decay or change.
He holds the universe by his power; never shaped by it, but shaping all that is.

If the universe is vast beyond imagination, what’s greater is the One who says, “I am the Alpha and the Omega, the First and the Last, the Beginning and the End” (Revelation 22:13).

If cosmic distances leave us speechless, bigger still is the love that spans them.
If galaxies fade and worlds dissolve, bigger still is the hope that will never end.

Where the Vastness of Space Meets the Nearness of God

Every question we ask about the heavens eventually points back to its Author. We can measure galaxies, chart their motion, and trace light that began billions of years ago. Yet, at the edge of every discovery, the same realization awaits: there is more.

Science reveals how the universe works. Faith reveals why it exists.

The more we learn about creation, the more clearly we see multiple purposes woven into its structure. Every constant, every law of physics, every beam of light reflects intention rather than accident. The universe operates with precision that invites not only study, but also worship of the One who brought it into being.

And yet, the greatest wonder is not merely that God created such an expansive cosmos, it’s that he entered it.

The Creator who set galaxies in motion also stepped into human history. The Word who spoke light into existence became the Light of the world.

That truth reframes every discovery. The universe doesn’t point us away from God; it draws us toward him. Each observation deepens our understanding of his power and our gratitude for his presence.

If you’d like to explore further, you can find more insights in our resource library—or dive deeper through Dr. Hugh Ross’s book, Why the Universe Is the Way It Is, a look at how the cosmos reveals the wisdom and purposes of its Creator.

Because in the end, every light-year, every law, and every living soul testifies to one truth:

The universe was made on purpose, by a God who hung the galaxies in place and still holds us close to his heart.

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The question, “Is astrology real?” is one that millions of people contemplate. In the US alone, a recent study revealed that roughly 60 percent of American adults accept at least one “New Age” belief, with nearly a third specifically believing in astrology.

Even more surprising, many who identify as Christians also embrace these beliefs in their own life alongside their faith.

But what does scientific study and the evidence actually tell us? And more importantly, what guidance does the Bible offer on astrology and its practices?

What is Astrology?

Astrology is the ancient belief system that the stars—which includes various celestial bodies (planets, moons, solar systems, etc.)—set the destinies for individual people, groups of individuals, and for the events among nations.

In practice, astrologers attempt to use the positions of celestial bodies to make predictions about the lives and affairs of human beings and the events among nations in the world. Astrologers believe that the positions of the stars and planets at the specific time of a person’s birth affect their personality, temperament, mood, environment, and future course of life events.

Astrologers then use these calculations to create horoscopes that are personalized by specific dates of birth to both predict and affect one’s destiny. While some astrologers study the balance of elements in a person’s horoscope to interpret their personality, others use astrological calculations to help people make decisions and optimize their personal strengths in life.

Where Did Astrology Come From?

The practice of astrology has deep roots in the ancient world and originated in Mesopotamia as early as the third millennium BC. Astrology was initially used to interpret celestial cycles and predict seasonal shifts.

• The Babylonians used the stars and planets to interpret omens from the various gods. They developed the zodiacal system, which divides the heavens into twelve constellations.
• The ancient Egyptians believed that constellations were patterns of stars that the sun appeared to traverse through at specific times of the year.
• In ancient China, noblemen used eclipses and sunspots to predict good or bad times for the reign of a given emperor.
• The ancient Mesopotamians and Egyptians are generally considered the originators of the Western practice of astrology. Astrology spread to India and China.
• The ancient Greeks developed the zodiac symbols and names used in today’s astrology.

The Greeks are credited with distinguishing the scientific practice of astronomy from astrology, with Claudius Ptolemy, an astrologer and astronomer from Alexandria, Egypt, establishing the foundation of Western astrology in his book Tetrabiblos.

Why Are People So Intrigued by Astrology?

People are drawn to astrology for numerous complex reasons that blend spiritual seeking, psychological needs, and cultural influences. Here are some of the main factors:

1. From a biblical perspective, the heavens exhibit the glory of God (Psalm 19:1–4). So people, whether they are fully aware of it or not, are receiving general revelation about the nature and glory of God. This is a spiritual, moral, and aesthetic experience and people may mistakenly associate aspects of this revelation with the claims of astrology.
2. Again from the Bible, the fallen nature of human beings makes worshippers into idolaters (Romans 1). Sinful people have a natural tendency to reject God but they intuitively replace him in their worship with other objects, with the cosmos being an attractive alternative. Some people even view astrology as a way to explore their spirituality and to connect with the cosmos in a spiritual and religious way.
3. People have an important aesthetic appreciation and attraction. Since the heavens abound with a beauty all their own, that natural aesthetic serves to draw people to its gaze and to consider its purpose and significance in life. 
4. One of the practical factors in our everyday lives is the need and desire to gain objective insights about one’s personality, relationships, and critical life events. Astrology offers a sense of guidance by providing interpretations via the so-called wisdom of the stars.
5. From a practical perspective, astrology can serve as a convenient, inexpensive, and easy coping mechanism. During difficult times of stress, anxiety, and uncertainty in life, astrology can offer a sense of structure and predictability, allowing people to feel more in control of their complex lives.
6. Astrology can offer social connection and a sense of belonging with people who together seek wisdom, knowledge, and guidance through their common zodiac sign and horoscope predictions.

Statistics on Belief in Astrology:

• The American Federation of Astrologers indicated that about 70 million Americans read their horoscope daily.
• In 2018, 29% of American adults said they believed in astrology, including 26% of Christians.
• In 2022, 27% of Americans said they believed in astrology, including 37% of adults under 30.
• In 2024, 70% of Americans said they either “somewhat” or “strongly” believed in astrology.

The Difference Between Astrology and Astronomy

While astrology and astronomy have very different definitions today, historically, the scientific discipline of astronomy grew out of the practice of astrology.

Astronomy researches everything outside of the earth’s atmosphere, including celestial realities such as planets, stars, asteroids, comets, black holes, galaxies, and the broader universe itself. This systematic scientific study involves principles of mathematics and physics, using direct observation and testing, critical features of science.

In contrast, astrology is a belief system that assumes the positioning of stars and planets influences human events and behavior. The Western scientific community views astrology as pseudoscience because it lacks a scientific basis grounded in observation and testing.

Reasons to Believe’s (RTB) staff scholars and scholar community include PhD-trained scientists who are professional astronomers, astrophysicists, and cosmologists.

How Does Astrology Work?

Astrology is the mystical/magical belief system that the alignment of celestial bodies affects every individual person’s mood, personality, and environment, depending on when he or she was specifically born. Astrologers draw information from the zodiac and print horoscopes in newspapers and other sources that are personalized to one’s birth date.

The practice centers around creating and interpreting natal charts (sometimes called birth charts), which are essentially maps of where all the planets were located at the exact moment you were born. Astrologers believe these celestial positions influence different aspects of your personality and life.

For example, the position of the Sun determines your “sun sign” (the zodiac sign most people identify with), while the Moon’s position allegedly influences your emotions and private self. Each planet supposedly governs different areas of life—Venus for love and relationships, Mars for energy and aggression, Jupiter for luck and growth, etc.

Modern astrologers have expanded these basic interpretations into complex systems involving “houses” (representing different life areas) and “aspects” (the angles between planets). Different astrological traditions (Western, Vedic, Chinese) have their own variations of these principles.

Many astrologers claim to personalize readings based on these celestial patterns, creating the impression of a tailored message from the cosmos. In actuality, as we’ll see, there’s little evidence supporting these claims beyond coincidence and psychological factors.

Is Astrology True?

To help answer this thoroughly, we’re breaking it down into multiple questions that can be clearly defined and answered.

Is Astrology Real?

Horoscopes tend to work (appearing true, real, and accurate) but in a tricky and deceiving manner. Horoscope columnists write daily predictions that are applicable but also quite flexible. They can seem personal, giving the illusion of genuine knowledge and truth, but are often vague enough to avoid the risk of falsification.

John Ferrer writes: “Let’s be clear, though. By all scientific measures, horoscopes, the zodiac, and astrology lack reliable, specific, explanatory, or predictive power. Horoscopes do not ‘work’ in any scientifically credible way. They only seem to work because of different cognitive biases and parlor tricks like confirmation bias, the Barnum effect, cold-reading, placebo effect, educated guessing, self-fulfilling prophecy, and raw probabilities.”

From a Christian perspective, we need to consider whether there might be spiritual forces involved in astrology. The Bible warns about deception and spiritual practices that draw us away from God. While many people approach astrology casually, Scripture indicates that divination practices can potentially open doors to spiritual influence that isn’t divine in origin.

This doesn’t mean every horoscope reader is experiencing direct demonic influence, but it does suggest we should approach these practices with spiritual discernment and caution. The apparently “working” nature of astrology for some people might stem from psychological factors—or in some cases, from spiritual sources that Scripture warns against.

Is Astrology Accurate?

When it comes to horoscopes, they are overly general and lacking in specificity. Astrology has been shown to be highly unreliable in providing genuine information about people’s lives. Horoscopes never seem to make direct claims that can be objectively proven true or false.

Several psychological phenomena explain why people might feel astrology is accurate:

1. The Barnum effect: This is the tendency to accept vague, general statements as uniquely applicable to oneself. Horoscopes typically contain statements that could apply to almost anyone.
2. Confirmation bias: We naturally remember the hits and forget the misses. If your horoscope makes ten predictions and one comes true, you’re likely to remember only the accurate one.
3. Self-fulfilling prophecy: If your horoscope says you’ll have a confrontation today, you might become more defensive or sensitive, actually creating the predicted outcome.

Many scientific studies have examined astrological accuracy. In one famous experiment, psychologist Bertram Forer gave students a “personalized” personality assessment that was actually identical for everyone. Despite receiving the same generic description, students rated the accuracy of their “personal” assessment as 4.26 out of 5 on average.

Similar experiments have repeatedly demonstrated that people typically can’t distinguish between genuine astrological readings and random or fake ones.

Is There Any Truth in Astrology?

Truth has traditionally been defined as that which corresponds to reality (reflecting a realist or correspondence theory of truth). Astrology has a very poor record when it comes to the real and the true. Astrology trades on deception and doesn’t risk the chance of being shown false. Astrology is also an act and practice that the Creator God of the Bible forbids and condemns.

While the cosmos certainly reveals God’s glory as the psalmist declares, astrology misinterprets this revelation. Rather than pointing to the Creator, it elevates the creation itself as the source of meaning and guidance. This fundamental error takes us away from rather than toward ultimate Truth.

From a Christian perspective, truth isn’t merely factual accuracy but alignment with God’s revelation and purposes. Astrology may occasionally stumble upon factual truths by chance, but it isn’t rooted in the Truth that sets us free. Instead, it presents an alternative system of meaning that competes with biblical revelation.

Astrology and Science: Is Astrology Scientific?

The scientific community widely criticizes astrology as a pseudoscience due to a lack of evidence supporting its claims, inconsistent results in testing, no plausible mechanism for how celestial bodies could influence human lives, and the inability to make falsifiable predictions, meaning it cannot be definitively disproved through scientific methods. Essentially, astrology fails to meet the basic criteria of a scientific theory.

What Types of Tests and Experiments Have Scientists Performed on Astrology?

The basic scientific problem with astrology is that it fails to explain how the positions of planets and stars could in fact exert a physical force on humans to influence their personalities or life events.

Numerous scientific studies have failed to find any evidence supporting astrological predictions beyond chance occurrences and manipulation. Let’s look at some notable scientific examinations of astrology:

1. The Carlson Double-Blind Study (1985): This landmark study published in Nature asked professional astrologers to match birth charts to psychological profiles. Under controlled conditions, the astrologers performed no better than chance.
2. The McGrew and McFall Study (1990): This examination tested whether astrologers could match natal charts to psychological profiles of individuals. Again, the results showed no better than random matching.
3. The Shawn Carlson Study (1985): In another controlled experiment, astrologers failed to match birth charts with the correct California Psychological Inventory profiles of test subjects.
4. Statistical Analysis of Personality Traits: Multiple studies have examined whether people born under the same sign show similar personality traits. These studies consistently find no correlation between birth signs and personality.
5. Twin Studies: Research examining the lives of twins (born minutes apart under identical astrological conditions) shows significant divergences in personality and life outcomes, contradicting astrological expectations.
6. Michel Gauquelin’s Mars Effect: Though initially suggesting a statistical correlation between athletic champions and Mars’s position at birth, subsequent rigorous analysis failed to replicate these findings when selection biases were controlled.

What’s particularly notable is that when astrologers are tested under scientifically controlled conditions that prevent cold reading and other psychological techniques, their accuracy falls to levels consistent with random chance.

Does Psychology Influence the Belief in Astrology?

Psychology can significantly influence the belief in astrology. For example, factors like the Barnum effect, personality traits like openness and narcissism, and the deep desire for meaning in life contribute to why people might find astrology personally appealing.

Several psychological factors help explain why astrology remains popular despite lacking scientific support:

• The Barnum Effect: Named after P. T. Barnum, this effect occurs when individuals believe vague, general statements apply specifically to them. Astrological readings typically contain statements general enough to apply to almost anyone, yet people perceive them as uniquely personal.
• Illusion of Control: In times of uncertainty or stress, astrology can provide a sense of order and predictability, helping people feel they have some control over unpredictable aspects of life.
• Confirmation Bias: People tend to remember predictions that come true while forgetting those that don’t, reinforcing their belief in astrology’s accuracy.
• Need for Meaning: Humans naturally seek patterns and meaning in life events. Astrology provides ready-made explanations for personality traits, relationships, and life challenges.
• Self-Discovery Tool: Regardless of its validity, many people use astrological frameworks as tools for self-reflection and understanding.
• Social Identity: Identifying with a zodiac sign can provide a sense of belonging and social identity, fulfilling basic psychological needs.
• Cognitive Dissonance: Once someone has invested time and identity in astrological beliefs, they’re likely to interpret new information in ways that support rather than challenge these beliefs.

Research has also found that people are more likely to turn to astrology during times of personal crisis or stress. One scientific study showed increased internet searches for astrological information following economic downturns or political uncertainty.

These psychological factors don’t mean astrology works—just that our minds are predisposed to find meaning in such systems regardless of their objective validity.

What Does the Bible Say About Astrology?

The Bible forbids involvement with the secret and hidden practices of the occult. Historic (biblical) Christianity forbids involvement with all types of divination (the practice of using omens, rituals, or supernatural powers to gain insight into the future or the present).

The Bible’s stance on astrology and divination is remarkably consistent throughout both the Old and New Testaments. God repeatedly warns his people against seeking guidance from the stars rather than from him directly.

In Deuteronomy 18:10–12, we find a comprehensive prohibition: “Let no one be found among you who sacrifices their son or daughter in the fire, who practices divination or sorcery, interprets omens, engages in witchcraft, or casts spells, or who is a medium or spiritist or who consults the dead. Anyone who does these things is detestable to the LORD; because of these same detestable practices the LORD your God will drive out those nations before you.”

Isaiah 47:13–14 specifically addresses astrologers: “All the counsel you have received has only worn you out! Let your astrologers come forward, those stargazers who make predictions month by month, let them save you from what is coming upon you. Surely they are like stubble; the fire will burn them up. They cannot even save themselves from the power of the flame.”

In the New Testament, Acts 19:18–19 describes new believers renouncing divination practices: “Many of those who believed now came and openly confessed what they had done. A number who had practiced sorcery brought their scrolls together and burned them publicly

These passages reveal that seeking guidance from the stars rather than from God is not merely misguided but actively opposed to God’s will for his people. From a biblical perspective, astrology represents a form of spiritual rebellion—looking to creation rather than the Creator for ultimate guidance.

Horoscopes

Horoscopes are perhaps the most widespread expression of astrological practice in contemporary culture. These daily, weekly, or monthly forecasts purportedly offer insights into your future based on your birth sign. But what does the Bible say about horoscopes?

Scripture makes it clear that only God knows the future (Isaiah 46:9–10), and attempting to divine it through other means constitutes a form of spiritual infidelity. Horoscopes represent a substitute for divine guidance—offering a counterfeit form of wisdom that the Bible explicitly warns against.

The deceptive nature of horoscopes aligns with what Scripture tells us about false prophets and teachings. In Matthew 7:15, Jesus warns about false prophets who “come to you in sheep’s clothing, but inwardly they are ferocious wolves.” Horoscopes may seem harmless or even helpful, but they can lead people away from genuine spiritual truth.

From a practical standpoint, horoscopes typically offer vague predictions that could apply to almost anyone. This ambiguity allows readers to project their own meanings onto the text—creating an illusion of insight without delivering genuine prophetic knowledge. The Bible, by contrast, affirms that God’s guidance is clear, truthful, and aligned with his character and purposes.

Christians seeking guidance should turn to prayer, Scripture, and the counsel of mature believers rather than horoscopes. As James 1:5 promises: “If any of you lacks wisdom, you should ask God, who gives generously to all without finding fault, and it will be given to you.”

Zodiac Signs & Celestial Bodies

The concept of zodiac signs emerged from ancient Babylonian astrology and was later refined by Greek astronomers. These twelve signs, each associated with a constellation, allegedly influence human personality and destiny based on the Sun’s position at birth.

Some Christians who use astrology may refer to Psalm 19:1:

Yes, God created the stars, but the stars weren’t created for our personal divination or revelation.

While Scripture acknowledges the beauty and order of the universe, it consistently points to it all as evidence of God’s creative power—not as sources of personal guidance. Genesis 1:14 states that God created the stars “to separate the day from the night” and “to mark sacred times, and days and years.” Their purpose is to aid in navigation and timekeeping, not to dictate human personality or destiny.

Some Christians who use astrology will point out the magi (three wise men) as astrologers, as if that supports/condones the practice. As Joe Carter explains: “Their description of seeing a celestial body as a portent of a significant event appears to be a type of mundane astrology (i.e., the study of significant celestial moments to social groups, nations, or all of humanity). Even if the magi (a term from which we get the word ‘magic’) were actual astrologers, this would not be a biblical endorsement of astrology. Instead, it would be an example of how even pagans would recognize Jesus as God.”

The magi’s journey illustrates how God can use various means to draw people to himself, even working through imperfect understanding. However, their story doesn’t validate astrological practices any more than Balaam’s story validates pagan divination (Numbers 22–24).

In fact, the magi story reveals something profound: these stargazers ultimately abandoned their astrological instruments to bow before the incarnate Word of God. Their journey represents movement away from various forms of divination toward direct worship of the true Source of wisdom.

The True Source of Wisdom

If astrology and horoscopes don’t provide reliable guidance, where should we turn? The Bible points us to God himself as the ultimate source of wisdom and direction for our lives.

God’s Word

The Bible includes many references to wisdom, especially in Proverbs, Psalms, and Ecclesiastes.

Consider the following verses from the book of Proverbs:

• Proverbs 2:6: “For the LORD gives wisdom; from his mouth come knowledge and understanding”
• Proverbs 1:7: “The fear of the LORD is the beginning of knowledge”
• Proverbs 11:2: God’s wisdom is a safeguard for our lives
• Proverbs 16:16: Wisdom and insight are more valuable than material wealth
• Proverbs 19:20: “Listen to advice and accept discipline, and at the end you will be counted among the wise.”

Consider also the following verses from the New Testament book of James:

• James 1:5: “If any of you lacks wisdom, you should ask God, who gives generously to all without finding fault, and it will be given to you.”
• James 3:17: “But the wisdom that comes from heaven is first of all pure; then peace-loving, considerate, submissive, full of mercy and good fruit, impartial and sincere.”

Unlike astrological guidance, biblical wisdom comes with clarity and purpose. It’s not about divining the future but developing discernment to navigate life’s challenges with God’s character as our compass. While horoscopes offer vague predictions applicable to anyone, Scripture provides specific principles that transform our thinking and living.

God’s wisdom also comes through prayer, thoughtful study of Scripture, counsel from mature believers, and the gentle guidance of the Holy Spirit. These sources of wisdom bring us into closer relationship with God—unlike astrology, which creates dependence on impersonal cosmic forces.

True wisdom isn’t about knowing what will happen tomorrow; it’s about knowing the One who holds tomorrow. As we grow in relationship with God, we develop the discernment to recognize his guidance in our daily lives.

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