For millennia, we have looked to the darkness to find our place in the universe. We have mapped distant galaxies and charted the planets in the cold, outer reaches of our solar system. Yet, one of our most significant cosmic frontiers is not defined by immense distance, but by an overpowering proximity to light. There is a profound blind spot in our celestial neighborhood, a region hidden in plain sight, veiled by the brilliant glare of our own Sun.

The search for what lies within this area has been historically difficult. Pointing powerful telescopes toward the Sun is a practical way to destroy their sensitive optics, leaving the space inside the orbit of Venus as a largely unknown territory. What has the source of our system’s life and light been concealing? A recent shift in technology and perspective is finally allowing astronomers to find out. By daring to look toward the glare in the fleeting moments of twilight, we are discovering a population of hidden worlds. This is more than a story of scientific achievement; it is a story about learning to see what has always been present, and it carries a powerful echo for our own inner journeys of discovery.

The Veiled Frontier

It’s a strange paradox: the very thing that gives our solar system life and light also serves as a veil. For as long as we’ve had telescopes, astronomers have known you simply don’t point them anywhere near the Sun. It’s a basic rule of self-preservation—the Sun’s brilliance would fry their sensitive instruments instantly. But that one rule has turned the space inside Venus’s orbit into what scientists call a “notoriously challenging region for observations.” It’s a place that’s hidden from us simply because it’s too close to the light.

So, if you can’t look directly, how do you even begin to search? The only real shot astronomers have is during the fleeting moments of twilight. We’re talking about that brief window right after sunset or just before sunrise. The Sun has dipped below the horizon, so it’s safe to look in that direction, but its leftover light still catches any nearby objects, making them stand out against a darkening sky. It’s an incredibly narrow window, and it’s the only chance we get to glimpse what’s inside.

What this all means is that there’s a huge blind spot in our map of the solar system. An entire population of objects has existed mostly in theory, and the proof is in the numbers. To put it in perspective, astronomer Scott Sheppard of the Carnegie Institution for Science notes, “Only about 25 asteroids with orbits completely within Earth’s orbit have been discovered to date because of the difficulty of observing near the glare of the sun.” That tiny number isn’t because the region is empty. It’s a reflection of our own limited ability to see. It’s a powerful reminder that the biggest mysteries aren’t always hidden in the dark—sometimes, they’re obscured by too much light.

Piercing the Veil: The New Observers of Twilight

So, if looking toward the Sun was off-limits for so long, what changed? Instead of shying away from the glare, astronomers decided to lean into it. They developed a new strategy known as the “twilight survey,” a conscious and deliberate choice to explore a domain that was long considered forbidden territory. It required a fundamental shift in perspective, along with a new generation of technology designed for this unique challenge.

This new quest is being led by two impressive technological tools, each playing a different but complementary role. The first is the Zwicky Transient Facility (ZTF) in California, which acts like a wide-angle lens for the cosmos, scanning the entire northern sky every few nights. Its power is its speed and breadth.

The second is the Dark Energy Camera (DECam) in Chile, a deep and sensitive eye that can spot things much fainter than ZTF can. As Scott Sheppard, who runs a twilight survey with the instrument, puts it, DECam can “cover large areas of sky to depths not achievable on smaller telescopes, allowing us to go deeper, cover more sky, and probe the inner Solar System in ways never done before.”

But just as this precious window has been opened by new technology, a new kind of glare is threatening to close it. The proliferation of satellite mega-constellations is increasingly streaking astronomical images, and twilight observations are especially vulnerable. A 2022 study found that the fraction of ZTF twilight images affected by satellite trails shot up from less than 0.5% to 18% in just two years. The race is now on to map this hidden frontier before it’s veiled once more by an artificial curtain.

First Messengers from the Glare

All this searching wasn’t just theoretical. The abstract hunt for a hidden population of asteroids became a concrete reality with the discovery of two remarkable objects. These aren’t just data points; they are the first messengers from that veiled frontier, each with a unique character and a different story to tell about the extreme environment so close to our Sun.

The first arrived on January 4, 2020. A team using the Zwicky Transient Facility spotted an object on an unprecedented path: the first asteroid ever found to have its entire orbit tucked inside that of Venus. Its discovery confirmed a whole new class of asteroids, now called “Vatiras.” More surprising was its size, estimated to be comparable to a small mountain.

Formally named 594913 ꞌAylóꞌchaxnim (pronounced ai-LOH-chakh-nym), its name means “Venus girl” in the Luiseño language, a gesture honoring the indigenous people on whose ancestral lands the observatory sits. ꞌAylóꞌchaxnim is the stable, established resident of this previously unknown land.

A year and a half later, a second messenger appeared, this one with a very different personality. Discovered by Scott Sheppard with the deep-seeing Dark Energy Camera, 2021 PH27 is an object defined by extremes. It holds the record for the shortest orbital period of any known asteroid, whipping around the Sun in just 113 days. Its orbit slingshots it so close to the Sun that its surface is thought to reach temperatures “hot enough to melt lead.” Unlike ꞌAylóꞌchaxnim, this one seems to be just passing through. Its highly tilted orbit suggests it’s likely an extinct comet from the outer solar system, flung into its current, perilous path. If ꞌAylóꞌchaxnim is the hidden native, 2021 PH27 is the mysterious traveler, living a fast and dangerous life in the Sun’s inner sanctum.

Redrawing Our Cosmic Map

So what does finding these objects really mean? It’s more than just adding a few new dots to a chart; it forces us to fundamentally redraw our map of the solar system. The discovery of ‘Ayló’chaxnim officially confirmed the existence of a new class of asteroids called “Vatiras,” those with orbits entirely inside that of Venus. This, in turn, makes the hunt for the next theoretical group—the “Vulcanoids,” which would orbit entirely inside Mercury’s path—feel much more plausible. Each discovery gives us a new set of questions.

One of the biggest questions is how these objects got there in the first place. Did a mountain-sized rock like ‘Ayló’chaxnim actually form so close to the Sun, or did it migrate inward over time? Many scientists believe the answer lies in a subtle but powerful force called the Yarkovsky effect. It works like this: as an asteroid rotates, its “afternoon” side gets warmest.

When that side radiates heat into space, it creates a tiny, continuous thrust. Over millions of years, that gentle push of sunlight can act as a brake, causing the asteroid to slowly spiral inward from the main asteroid belt. It’s a powerful idea—that something as delicate as escaping heat can move mountains across the solar system.

Beyond the science, there are critical, practical reasons to complete this new map. For years, planetary defense programs have worked to catalog large, “planet-killer” asteroids, but there has been a lingering consensus that the last few might be the ones hiding in the Sun’s glare. The twilight surveys are proving this concern valid. They have already found at least one such object, 2022 AP7, an asteroid about a kilometer wide whose orbit could one day bring it into Earth’s path. Understanding this hidden population is not just an academic exercise; it’s an essential part of knowing our cosmic neighborhood and ensuring we see any potential hazards before they surprise us.

Seeing in the Light of Consciousness

This scientific quest to peer through the Sun’s glare is more than a story of technology; it resonates with one of humanity’s most timeless journeys: the search for self-knowledge. Across cultures, the Sun serves as the ultimate symbol for consciousness and the Self. And in this story, we find the deepest connection. Just as the physical Sun illuminates our solar system while concealing the worlds closest to it, our own awareness makes all experience possible, yet its very radiance can veil parts of ourselves. It is the invisible light by which we see, and often the most difficult thing to see into.

The act of the twilight survey, then, becomes a powerful allegory for a kind of deep introspection. The astronomers made a conscious choice not to look away from the overwhelming source, but to look carefully toward it to find what was hidden. This mirrors a profound spiritual practice—not just exploring what lies in our personal darkness, but developing the capacity to see what is hidden in our own light. It is a quest to perceive the subtle aspects of our own minds that are veiled by the everyday brightness of our own awareness.

Ultimately, every scientific discovery that moves a piece of the universe from an “unknown unknown” to something known is an expansion of consciousness. The journey to find these hidden worlds—from recognizing a collective blind spot, to developing a new way of seeing, to finally meeting the first messengers from the glare—is a powerful, living story. It is a reflection of the human drive to illuminate the unknown, whether it orbits our star or resides in the depths of our own being.

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