# This Asteroid May Be Three Worlds Fused Together

An episode of [Bedtime Astronomy](https://invisiblenetwork.ai/podcast/1736397134), 27 Aug 2026, 31 min.

Audio: https://dts.podtrac.com/redirect.mp3/api.spreaker.com/download/episode/73776445/asteroidp.mp3

Astronomers may have discovered a rare contact trinary in the asteroid belt: asteroid 44 Nysa appears to be three distinct bodies fused together. High-resolution observations reveal a striking three-lobed shape, while a tiny moon orbiting Nysa is helping scientists measure its mass and density. The findings could reveal whether Nysa is solid rock or a rubble pile—and how the earliest planetary bodies formed. Thank you for listening to Bedtime Astronomy — your guide to the cosmos. New episodes on space exploration, NASA missions & the latest astronomy breakthroughs. This episode includes AI-generated content.

## Transcript

[0:03] Speaker 1: Welcome to Bedtime Astronomy. Explore the wonders of the cosmos
[0:07] Speaker 1: with our soothing Bedtime Astronomy podcast. Each episode offers a
[0:12] Speaker 1: gentle journey through the stars, planets, and beyond, perfect for
[0:16] Speaker 1: unwinding after a long day. Let's travel through the mysteries
[0:20] Speaker 1: of the universe as you drift off into a peaceful
[0:22] Speaker 1: slumber under the night sky.
[0:27] Speaker 2: What shape is an asteroid?
[0:28] Speaker 3: Yeah, that's it sounds like a question a kid might ask.
[0:32] Speaker 2: You, right, exactly, It's a seemingly simple, innocent question. But
[0:36] Speaker 2: if you actually stop and think about it, if you
[0:38] Speaker 2: consider the history of how we've looked up at the
[0:40] Speaker 2: night sky for the vast, vast majority of human history,
[0:44] Speaker 2: the honest answer has just been you know, nobody.
[0:47] Speaker 3: Knows, right, because for centuries they've literally.
[0:50] Speaker 2: Just been dots, just tiny featureless points of light, right
[0:55] Speaker 2: crawling against the backdrop of the stars. I mean, if
[0:58] Speaker 2: you look at the etymology, the word destroid actually means starlike.
[1:03] Speaker 3: Which makes total sense because when you look at them
[1:05] Speaker 3: through a traditional telescope, that is exactly what they appear
[1:09] Speaker 3: to be. They don't they don't resolve into planetary.
[1:12] Speaker 2: Disks, right, No visible weather systems or rings or anything.
[1:15] Speaker 3: Exactly due to the diffraction limits of early optics, and
[1:18] Speaker 3: honestly just the sheer distance involved their dispecs. They're just
[1:22] Speaker 3: mathematical coordinance in the dark, which has to.
[1:24] Speaker 2: Be incredibly annoying for planetary scientists.
[1:26] Speaker 3: Oh, it's more than a minor annoyance. It's been a
[1:29] Speaker 3: fundamental roadblock in understanding our own cosmic neighborhood, because when
[1:33] Speaker 3: you can only observe a dot of light, you're forced
[1:37] Speaker 3: to categorize the entire solar system based just on how
[1:41] Speaker 3: that tiny point flickers.
[1:42] Speaker 2: So you're working with this massive data deficit right from
[1:46] Speaker 2: the start.
[1:47] Speaker 3: You really are. I mean, you know something is out there,
[1:49] Speaker 3: and you can track its orbit, sure, and you can
[1:51] Speaker 3: maybe use spectroscopy to guess what the surface is made of,
[1:54] Speaker 3: but the actual physical geography of the object that remains
[1:58] Speaker 3: entirely hidden.
[1:59] Speaker 2: Well, today, hey, you and I are embarking on a
[2:01] Speaker 2: mission to unravel the mystery of one specific, highly unusual
[2:05] Speaker 2: space rock that has pushed the absolute boundaries of our
[2:09] Speaker 2: observational tech. It's known as Asteroid forty four, and meisa.
[2:13] Speaker 3: Oh, Nisa. That is a name that commands a profound
[2:15] Speaker 3: amount of respect and frankly frustration in astronomy circles. It's
[2:19] Speaker 3: a world that has teased us for generations.
[2:22] Speaker 2: Okay, let's unpack this, because this isn't just a casual
[2:24] Speaker 2: conversation about a weirdly shaped rock tumbling through the void
[2:27] Speaker 2: between Mars and Jupiter. This is about fundamentally understanding the
[2:31] Speaker 2: building blocks of our own solar system.
[2:34] Speaker 3: Absolutely, It's about looking at a piece of cosmic debris
[2:37] Speaker 3: and trying to read the physical history of the universe
[2:40] Speaker 3: written right there on its surface.
[2:42] Speaker 2: Right Because Nisa isn't just a rock, it is a
[2:44] Speaker 2: time capsule. It's a physical remnant from that chaotic, violent
[2:48] Speaker 2: era when the planets, you know, including the Earth we're
[2:51] Speaker 2: sitting on right now, we're actively being forged out of
[2:54] Speaker 2: dust and gas.
[2:56] Speaker 3: The steaks are incredibly high with primordial bodies like this.
[3:00] Speaker 3: Every time we manage to resolve the actual shape of
[3:02] Speaker 3: a new asteroid, we aren't just getting a cool desktop wallpaper.
[3:06] Speaker 3: We are rigorously testing our overarching theories of planetary formation.
[3:11] Speaker 2: Like how does a microscopic grain of dust become a
[3:13] Speaker 2: pebble exactly?
[3:15] Speaker 3: And how does an aggregate of pebbles become a boulder?
[3:18] Speaker 3: And by what actual mechanical process do those boulders stick
[3:21] Speaker 3: together to build a whole world?
[3:23] Speaker 2: So to understand why NISSA so special and why it
[3:25] Speaker 2: holds the key to those massive questions, we first have
[3:28] Speaker 2: to understand why astronomers have been staring at it in
[3:31] Speaker 2: utter frustration for well over a century.
[3:33] Speaker 3: Let's start with the name asteroid forty four NISA.
[3:36] Speaker 2: That number forty four. It isn't just random, right, it's historical.
[3:40] Speaker 2: It signifies the order of discovery. So series is one,
[3:44] Speaker 2: palace is two, and so on, which.
[3:46] Speaker 3: Means being number forty four puts NYSSA very early in
[3:49] Speaker 3: the timeline of modern astronomy.
[3:51] Speaker 2: Right. It was discovered way back in eighteen fifty seven
[3:53] Speaker 2: by Hermann Goldschmidt. So for nearly one hundred and seventy
[3:56] Speaker 2: years we have known the specific rock was out there.
[4:00] Speaker 3: Yes, orbiting in the main asteroid belt between Mars and Jupiter.
[4:03] Speaker 3: And it's one of the brightest objects in that entire
[4:06] Speaker 3: sparse ring of debris.
[4:07] Speaker 2: Why is it so bright? Though?
[4:08] Speaker 3: That brightness is the crucial factor. NISA belongs to a
[4:11] Speaker 3: very specific, somewhat rare class of asteroids. It is an
[4:15] Speaker 3: E type asteroid, and it happens to be one of
[4:18] Speaker 3: the largest E types out there.
[4:19] Speaker 2: The E stands for enstotype right spot on.
[4:22] Speaker 3: N stay type is a specific type of silicate mineral,
[4:24] Speaker 3: a magnesium silicate. And what makes in state tide surfaces
[4:27] Speaker 3: so fascinating is that they are incredibly reflective. They have
[4:31] Speaker 3: a very high albedo.
[4:32] Speaker 2: Because most asteroids are pretty dark, aren't they.
[4:34] Speaker 3: Yeah, the vast majority are C type, which are carbonaceous.
[4:37] Speaker 3: They absorb most of the light that hits them. Think
[4:39] Speaker 3: of like the color and texture of a charcoal bri cat.
[4:42] Speaker 3: Oh wow, that dark, very dark. Or you have S
[4:46] Speaker 3: types which are stony and only moderately reflective. But E
[4:50] Speaker 3: types like NISA, they are brilliant. They reflect the massive
[4:53] Speaker 3: percentage of the sunlight that hits them.
[4:55] Speaker 2: So it's basically acting like a giant tumbling mirror out.
[4:58] Speaker 3: In deep space pretty much, which perfectly explains why Goldschmidt
[5:02] Speaker 3: was able to spot it so early in eighteen fifty seven.
[5:05] Speaker 3: Even though NISS is relatively small on a planetary scale,
[5:09] Speaker 3: it's acting like a cosmic beacon.
[5:11] Speaker 2: But here's the crux of the frustration for you guys.
[5:14] Speaker 2: Because it is so unusually bright, and because it has
[5:16] Speaker 2: this bizarre and state tight composition. It has been a
[5:21] Speaker 2: favorite high priority target for over one hundred.
[5:24] Speaker 3: Years, oh completely, generation after generation of astronomers at point
[5:27] Speaker 3: of their best instruments at it, trying to figure out
[5:29] Speaker 3: what it physically looks like, and.
[5:31] Speaker 2: For a century the data coming back has just been
[5:33] Speaker 2: maddeningly ambiguous.
[5:35] Speaker 3: It really has because before modern high resolution imaging, astronomers
[5:39] Speaker 3: were forced to rely on a technique called photometry to
[5:42] Speaker 3: generate light curves.
[5:43] Speaker 2: Which is an elegant concept but super indirect, very indirect.
[5:48] Speaker 3: As an asteroid rotates on its axis, the amount of
[5:51] Speaker 3: sunlight it reflects toward Earth changes depending on its shape.
[5:54] Speaker 2: So if you have a perfectly spherical asteroid, the surface
[5:58] Speaker 2: area facing US stays calm as it spins exactly.
[6:02] Speaker 3: Therefore, its light curve, which is just a graph of
[6:05] Speaker 3: its brightness over time, is a relatively flat straight line.
[6:08] Speaker 2: But if you have an elongated asteroid or something irregular,
[6:11] Speaker 2: the physics of that reflection changes entirely.
[6:14] Speaker 3: Right, when the broadside of a tumbling elongated rock faces Earth,
[6:17] Speaker 3: it reflects a ton of light in the curve spikes.
[6:20] Speaker 2: And then as it continues to rotate and the narrow
[6:22] Speaker 2: end points towards us, less light is reflected and the
[6:25] Speaker 2: curve disps.
[6:26] Speaker 3: You got it. So by measuring those peaks and valleys
[6:28] Speaker 3: and brightness over hours and days. Astronomers use complex mathematical
[6:32] Speaker 3: inversion models to try and reverse engineer a three D
[6:35] Speaker 3: shape from a two D line graph.
[6:38] Speaker 2: But that math is tricky, isn't it.
[6:40] Speaker 3: It's notoriously non unique. You can have entirely different physical
[6:44] Speaker 3: shapes that produce the exact same flickering pattern of light.
[6:48] Speaker 2: So you're just guessing basically.
[6:49] Speaker 3: For decades, the light curves of NISO were just screaming
[6:52] Speaker 3: at astronomers, I am not a sphere. The amplitudes of
[6:56] Speaker 3: the brightness variations were way too extreme for that.
[6:58] Speaker 2: So successive observations hinted it was elongated, maybe even bifurcated,
[7:03] Speaker 2: like two distinct lumps stuck together.
[7:05] Speaker 3: But that picture remained just a hypothesis. It was a
[7:09] Speaker 3: shadow on a graph, you know, a statistical probability, not
[7:13] Speaker 3: a physical place you could actually verify.
[7:15] Speaker 2: I like to think of this historical predicament like trying
[7:17] Speaker 2: to read a blurry license plate through a cheap pair
[7:20] Speaker 2: of binoculars from miles away on a really hot shimmering day.
[7:25] Speaker 3: That is a very accurate analogy, right.
[7:27] Speaker 2: You know, a car is there. You can see the
[7:28] Speaker 2: shape changing slightly as it turns. You can see the
[7:31] Speaker 2: sunlight glinting off the metal, but you just can't bring
[7:34] Speaker 2: it into focus.
[7:35] Speaker 3: The optical resolution simply isn't there. You're left guessing based
[7:39] Speaker 3: on blurry smudges. And the intellectual itch that creates for
[7:43] Speaker 3: a scientist is profound.
[7:45] Speaker 2: I can imagine you dedicate your career to studying this
[7:48] Speaker 2: object and it's just out of reach.
[7:50] Speaker 3: You know, a secret is hidden, just out of focus.
[7:53] Speaker 3: You know it's weird, you know it's not a normal rock,
[7:55] Speaker 3: but you cannot empirically prove your models.
[7:58] Speaker 2: Well, that exact intellectual itch is what drives the most
[8:02] Speaker 2: massive leaps in technological innovation. Astronomers didn't just throw up
[8:06] Speaker 2: their hands. They waited for the engineering to catch up.
[8:09] Speaker 3: And that brings us to the technological leap that finally
[8:12] Speaker 3: pierced through that century of blurry frustration.
[8:15] Speaker 2: And what I love is that this leap didn't come
[8:17] Speaker 2: from launching a multi billion dollar robotic probe to fly
[8:21] Speaker 2: past NISA.
[8:22] Speaker 3: No, it didn't. It came from two of the heaviest,
[8:24] Speaker 3: most advanced, most mind bogglingly complex instruments ever constructed on Earth,
[8:29] Speaker 3: firmly planted on the ground.
[8:31] Speaker 2: We are talking about an international team led by Kate
[8:34] Speaker 2: Minker at Lowell Observatory. They decided to tackle this enigma
[8:38] Speaker 2: using some absolute heightens of modern astronomy.
[8:40] Speaker 3: They utilized the shark Vias instrument mounted on the large
[8:43] Speaker 3: binocular telescope in Arizona, and they combine that with data
[8:47] Speaker 3: from this sphere's imple instrument on the very large telescope in.
[8:50] Speaker 2: Chile, Okay. To appreciate the magnitude of what Minker's team
[8:54] Speaker 2: accomplished here, we have to talk about the physical enemy
[8:57] Speaker 2: they were fighting. Why is looking at space from the
[9:00] Speaker 2: Earth so difficult?
[9:02] Speaker 3: The fundamental antagonist to ground based astronomy is our own atmosphere.
[9:06] Speaker 2: I mean, we obviously need it to breathe.
[9:09] Speaker 3: Sure, for survival, it's great, But for an astronomer're trying
[9:12] Speaker 3: to resolve a seventy five kilometer rock hundreds of millions
[9:15] Speaker 3: of miles away. The atmosphere is essentially a distorting funhouse.
[9:19] Speaker 2: Mirror because it's never static, right never.
[9:22] Speaker 3: It is a chaotic, turbulent, churning ocean of gas. You
[9:26] Speaker 3: have pockets of hot air rising, cold air sinking, extreme
[9:29] Speaker 3: wind shear, variations in humidity.
[9:31] Speaker 2: And all of that messes with the light exactly.
[9:34] Speaker 3: In optics, we measure how easily light travels through a
[9:37] Speaker 3: medium using an index of refraction. When air change is
[9:40] Speaker 3: temperature or density, there are fractive index changes.
[9:43] Speaker 2: So imagine the journey of the light. The sunlight hits NYSA,
[9:46] Speaker 2: bounces off and begins a pristine journey across millions of
[9:49] Speaker 2: miles of the absolute vacuum of space.
[9:51] Speaker 3: And in a vacuum, there's nothing to distort it. The
[9:54] Speaker 3: wavefront of that light is entirely flat and.
[9:57] Speaker 2: Uniform until the very last fraction.
[9:59] Speaker 3: Of a secon right. When that perfectly flat wavefront hits
[10:03] Speaker 3: the top of Earth's atmosphere, it enters that turbulent ocean.
[10:07] Speaker 3: It passes through thousands of moving pockets of air.
[10:10] Speaker 2: Each acting like a weird, weak little lens.
[10:13] Speaker 3: Bending and warping the light in random directions. So by
[10:16] Speaker 3: the time that light hits the telescope on the ground,
[10:18] Speaker 3: the flat wavefront looks like a crumpled up piece of paper.
[10:22] Speaker 2: This atmospheric distortion is exactly what causes stars to twinkle.
[10:26] Speaker 2: When you look up at night, isn't it.
[10:27] Speaker 3: Yes, The poet looks at a twinkling star and sees romance.
[10:32] Speaker 3: The astronomer looks at a twinkling star and sees a
[10:35] Speaker 3: catastrophically degraded data point.
[10:37] Speaker 2: That is hilarious but true. You guys call it astronomical seeing, right.
[10:41] Speaker 3: We do. If the atmosphere is particularly turbulent, the seeing
[10:44] Speaker 3: is bad and the point of light is smeared out
[10:46] Speaker 3: into a fuzzy, boiling blob on the sensor.
[10:49] Speaker 2: Traditionally, the only way to defeat this was just to
[10:52] Speaker 2: bypass the atmosphere entirely, put a telescope on a rocket
[10:55] Speaker 2: and put it in orbit, which.
[10:56] Speaker 3: Was the entire driving philosophy behind the Hubble space telescope.
[11:00] Speaker 3: Hubble isn't actually that large. Its mirror is only two
[11:03] Speaker 3: point four meters across.
[11:04] Speaker 2: But it's in a vacuum exactly.
[11:06] Speaker 3: It can achieve its maximum theoretical resolution without any atmospheric smearing.
[11:11] Speaker 2: But Minker's team studying NISA didn't use Hubble or James Web.
[11:16] Speaker 2: They use ground based telescopes equipped with adaptive optics.
[11:20] Speaker 3: Which is arguably one of the most brilliant opti mechanical
[11:23] Speaker 3: engineering feats of the last fifty years.
[11:25] Speaker 2: It sounds like science fiction. How do you physically correct
[11:29] Speaker 2: a chaotic, unpredictable atmosphere in real time?
[11:32] Speaker 3: The concept is to measure the exact distortion caused by
[11:35] Speaker 3: the atmosphere instantly, and then physically change the shape of
[11:39] Speaker 3: the telescope's mirror to introduce the exact opposite distortion.
[11:43] Speaker 2: Wait, you're bending a solid glass mirror. Are they bending
[11:46] Speaker 2: the giant primary mirror at the bottom of the telescope.
[11:48] Speaker 3: No? No, those primary mirrors are massive. The very large
[11:51] Speaker 3: telescope uses mirrors that are eight point two meters across
[11:53] Speaker 3: and weigh tons. They're totally rigid.
[11:55] Speaker 2: So where does the bending happen?
[11:57] Speaker 3: The adaptive optics system happens further down the optical path.
[12:01] Speaker 3: The light bounces off the giant primary mirror, up to
[12:03] Speaker 3: a secondary mirror and into an instrument suite that contains
[12:06] Speaker 3: a specially designed deformable mirror.
[12:09] Speaker 2: A deformable mirror, what is that actually made of?
[12:12] Speaker 3: It's an incredibly thin, flexible membrane of reflective material, sometimes
[12:16] Speaker 3: just a few millimeters thick, and mounted directly behind it
[12:19] Speaker 3: are thousands of microscopic actuators.
[12:22] Speaker 2: Like tiny pistons exactly.
[12:24] Speaker 3: Often voice coils or peas electric crystals that expand and
[12:28] Speaker 3: contract when you apply a voltage to them. They push
[12:30] Speaker 3: and pull on the back of the flexible mirror.
[12:32] Speaker 2: But the atmosphere changes millisecond to millisecond. How does the
[12:36] Speaker 2: computer know exactly how to bend the mirror that past?
[12:39] Speaker 3: You need a reference point, something whose original shape you
[12:42] Speaker 3: already know perfectly. Often they will shoot a powerful, precisely
[12:46] Speaker 3: tuned laser straight up into the night sky. Wait a laser,
[12:50] Speaker 3: yes tuned to excite a layer of sodium atoms sitting
[12:53] Speaker 3: about ninety kilometers up in the mesosphere. It's left over
[12:56] Speaker 3: dust from micrometeors burning up, So.
[12:58] Speaker 2: The laser hits the sodium, makes it glow right.
[13:01] Speaker 3: Creating an artificial guide star right next to the object
[13:03] Speaker 3: you actually want to look at.
[13:04] Speaker 2: That is wild. You are creating a fake glowing star
[13:08] Speaker 2: high in the atmosphere just to measure the blur.
[13:10] Speaker 3: Because you created it, you know the light originating from
[13:14] Speaker 3: it should be a perfect sharp point. A sensor in
[13:17] Speaker 3: the telescope. Look at how much that artificial star has
[13:21] Speaker 3: been smeared by the trip back down.
[13:23] Speaker 2: I see the loop. Now the sensor palculates the mathematical
[13:26] Speaker 2: inverse of this smear sends a signal to the tiny pistons,
[13:30] Speaker 2: and they pushed the mirror into a shape that perfectly
[13:33] Speaker 2: counteracts the distortion.
[13:35] Speaker 3: And the staggering part is the speed it measures the
[13:38] Speaker 3: distortion and physically bends the mirror hundreds sometimes thousands of
[13:42] Speaker 3: times every single second.
[13:44] Speaker 2: It's flattening out a churning ocean of air in real time.
[13:47] Speaker 3: It really is.
[13:48] Speaker 2: By doing this, Minker's team achieved something historic. They produced
[13:51] Speaker 2: the highest resolution images of NISA ever obtained. They describe
[13:56] Speaker 2: them as being close to spacecraft quality without ever leaving It's.
[14:00] Speaker 3: An astonishing achievement for ground based astronomy.
[14:03] Speaker 2: Now, wait a minute, let me push back on this
[14:04] Speaker 2: for a second. If we are getting spacecraft quality images
[14:07] Speaker 2: from ground based telescopes, how does that work practically? Does
[14:10] Speaker 2: this technology make sending robotic space probes redundant?
[14:14] Speaker 3: This raises an important question, and it is a debate
[14:17] Speaker 3: that echoes through funding agencies constantly. But the short answer
[14:20] Speaker 3: is absolutely not. Space probes are not remotely redundant.
[14:25] Speaker 2: Okay, why not? If we can just build better mirrors
[14:28] Speaker 2: on Earth? Why spend billions launching a fragile metal box
[14:32] Speaker 2: into the void.
[14:33] Speaker 3: Because the roles they play are totally different. Ground based
[14:37] Speaker 3: telescopes can be built unimaginably large. We're building the extremely
[14:41] Speaker 3: large telescope right now, which will have a primary mirror
[14:45] Speaker 3: nearly thirty nine meters across.
[14:46] Speaker 2: You definitely cannot fold up a thirty nine meter mirror
[14:49] Speaker 2: and pack it into a rocket exactly.
[14:51] Speaker 3: The raw light gathering power on the ground will always
[14:54] Speaker 3: scale faster and cheaper. Plus if it breaks, a technician
[14:57] Speaker 3: can just drive up the mountain and swap a circuit.
[14:59] Speaker 2: Board breaks, it's just gone right.
[15:02] Speaker 3: So for spotting faint objects or high res visual maps
[15:05] Speaker 3: of things we know exist, ground based adaptive optics is
[15:08] Speaker 3: the vanguard, but visual observation is just one narrow slice.
[15:11] Speaker 2: Of the pie right, and image is just photons hitting
[15:14] Speaker 2: a sensor.
[15:15] Speaker 3: A telescope on Earth cannot fly through the coma of
[15:18] Speaker 3: a comet and physically sample the dust. It can't use
[15:22] Speaker 3: a math spectrometer to smell the chemical outgassing. It can't
[15:25] Speaker 3: drop a lander to drill into the surface.
[15:28] Speaker 2: So the telescope provides the high resolution map, but the
[15:30] Speaker 2: spacecraft is required to actually walk the territory.
[15:34] Speaker 3: That is the perfect way to contextualize it. They are
[15:36] Speaker 3: highly complementary. We use the ground to survey thousands of
[15:40] Speaker 3: objects and find the weirdest anomalies like.
[15:43] Speaker 2: NYSA, and then you know exactly where to send the
[15:45] Speaker 2: probe later to get the best return on investment.
[15:47] Speaker 3: Exactly.
[15:47] Speaker 2: Okay, So let's return to the specific anomaly in question.
[15:51] Speaker 2: Minker's team points these colossal machines at NISA. The lasers
[15:55] Speaker 2: pierce the mesosphere, the mirrors vibrate thousands of times a second.
[15:59] Speaker 2: I midge finally resolves.
[16:01] Speaker 3: And it completely defies a century of careful modeling.
[16:03] Speaker 2: What did they actually see?
[16:05] Speaker 3: Well, the light curves had suggested an elongated potato shape,
[16:09] Speaker 3: maybe two lumps, but the adaptive optics images didn't just
[16:13] Speaker 3: show a lopsided rock. They clearly revealed two incredibly prominent,
[16:18] Speaker 3: deep valleys wrapping completely around the asteroid's circumference.
[16:21] Speaker 2: We aren't talking about shallow depressions here, right, No, these
[16:25] Speaker 2: are deep grooves, physical demarcations circling the entire massive rock
[16:30] Speaker 2: like it's pinched.
[16:31] Speaker 3: Yes, the team didn't interpret them as random craters or
[16:34] Speaker 3: fault lines. The morphology was too specific. They interpreted these
[16:38] Speaker 3: valleys as next pinched joints where entirely separate physical bodies
[16:43] Speaker 3: have come to rest against one another.
[16:45] Speaker 2: Suggesting that Nissa is not a single rock.
[16:48] Speaker 3: Right, the visual evidence strongly suggests it is composed of
[16:52] Speaker 3: three distinct bulbous lobes gently welded together into one structure.
[16:57] Speaker 2: Three distinct lobes.
[16:59] Speaker 3: That is astonished, It's breathtaking. Now, the concept of distinct
[17:02] Speaker 3: bodies sticking together isn't totally new. We call it a
[17:05] Speaker 3: contact binary.
[17:07] Speaker 2: Let's clearly define that, because when the average person hears
[17:09] Speaker 2: binary system, they usually think of two stars orbitting each
[17:13] Speaker 2: other at a distance.
[17:14] Speaker 3: Right, a standard binary is locked in a gravitational dance,
[17:17] Speaker 3: separated by space. But a contact binary means that two
[17:20] Speaker 3: bodies have actually physically touched and remain together.
[17:23] Speaker 2: How does that even happen? We're so conditioned by Earth's gravity.
[17:27] Speaker 2: If I smash two rocks together on Earth, they shatter.
[17:30] Speaker 3: Because on Earth things accelerate quickly and hit with immense
[17:33] Speaker 3: kinetic energy. But in the main asteroid belt, relative velocities
[17:37] Speaker 3: can be astaushingly.
[17:38] Speaker 2: Low because they're all orbiting the Sun and roughly the
[17:41] Speaker 2: same direction.
[17:42] Speaker 3: Exactly, if two asteroids are in very similar parallel orbits.
[17:47] Speaker 3: They aren't slamming into each other head on at mock twenty.
[17:50] Speaker 3: They might slowly drift toward each other at the speed
[17:52] Speaker 3: of a slow human walk.
[17:53] Speaker 2: And the gravity of a thirty kilometer rock is tiny,
[17:56] Speaker 2: so it doesn't accelerate the incoming object.
[17:58] Speaker 3: Right the mutual grasp Vitational acceleration is incredibly weak, so
[18:03] Speaker 3: when they finally touch, it's not a catastrophic collision. The
[18:06] Speaker 3: energy is absorbed by the surface dust acting like a
[18:09] Speaker 3: shock absorber.
[18:09] Speaker 2: It's like a deep space docking procedure between two mountains.
[18:12] Speaker 2: They just bump and stick.
[18:14] Speaker 3: And over millions of years, minor internal heating and micro
[18:17] Speaker 3: bombardment slowly welled them together at the neck. We have
[18:21] Speaker 3: spectacularly observed this.
[18:23] Speaker 2: Before Comet sixty seven P right the Rosetta mission. I
[18:26] Speaker 2: vividly remember those images. The whole world said it looked
[18:30] Speaker 2: exactly like a rubber duck floating in space.
[18:32] Speaker 3: Comet sixty seven P is a textbook contact binary. Two
[18:36] Speaker 3: distinct primordial icy bodies that drifted together and.
[18:40] Speaker 2: Docked, and there was another one, Eric coth Yes, deep.
[18:43] Speaker 3: In the Kuiper Belt. NASA's New Horizons spacecraft flew past
[18:47] Speaker 3: it in twenty nineteen. It looked like a flattened reddish snowman.
[18:51] Speaker 2: I remember NASA releasing those three D red blue anaglyph images.
[18:55] Speaker 2: You could perfectly see the depth of the two distinct
[18:57] Speaker 2: spherical lobes resting against each other.
[19:00] Speaker 3: Finding aricof provided physical proof that this gentle, slow sticking
[19:04] Speaker 3: together process is a foundational mechanism of planetary construction.
[19:08] Speaker 2: Well, here's where it gets really interesting when we bring
[19:10] Speaker 2: this back to Nysa. Nisa isn't a rubber duck. It
[19:13] Speaker 2: isn't a two lob snowman. If this interpretation of those
[19:16] Speaker 2: two deep valleys is correct, Nysa isn't a contact binary
[19:19] Speaker 2: at all.
[19:20] Speaker 3: It is a contact trinary, which.
[19:21] Speaker 2: Would be the very first one ever recorded in the
[19:23] Speaker 2: books out of millions of asteroids, the absolute first time
[19:26] Speaker 2: we've seen three distinct bodies doing this.
[19:28] Speaker 3: It establishes an entirely new kinematic paradigm.
[19:32] Speaker 2: I just want to pause and think about the sheer
[19:33] Speaker 2: statistical improbability of that. First, you need two massive bodies
[19:38] Speaker 2: to drift together at the exact right low velocity to
[19:41] Speaker 2: form the initial binary without shattering. Yes, then a third
[19:45] Speaker 2: massive body has to happen upon this fragile pair, match
[19:49] Speaker 2: their orbital velocity almost perfectly, and gently dock with them
[19:53] Speaker 2: softly enough that it doesn't break the original neck holding
[19:56] Speaker 2: the first two together.
[19:57] Speaker 3: The kinematic constraints required for a thing three body low
[20:01] Speaker 3: velocity merger are staggeringly tight. It implies a vastly more crowded,
[20:05] Speaker 3: dynamically complex environment in the early Solar System than we thought.
[20:10] Speaker 2: It's like finding a seventy five kilometer tall cairn of
[20:13] Speaker 2: balanced rocks floating in the void.
[20:15] Speaker 3: It really is. It suggests these slow motion multibody pile
[20:17] Speaker 3: ups might have been incredibly common during the primordial era.
[20:21] Speaker 2: But, as with all things in science, a single piece
[20:23] Speaker 2: of visual evidence rarely settles a debate immediately. Manker's team
[20:28] Speaker 2: left the door open for a completely different explanation.
[20:30] Speaker 3: They were obligated to because the visual morphology of the
[20:34] Speaker 3: asteroid allows for an alternative reading, broadly referred to as
[20:38] Speaker 3: the battered rock hypothesis.
[20:40] Speaker 2: Okay, let's explore this alternative. It suggests Nissa is a
[20:44] Speaker 2: single solid body that has just been so deeply battered
[20:49] Speaker 2: and indented by impacts that it merely resembles three lobes.
[20:53] Speaker 3: Right, It pausites. NISA started as one large monolith, and
[20:57] Speaker 3: over billions of years, it was subjected to massive kinetic
[21:01] Speaker 3: hits in exactly the right geometric locations to carve out
[21:04] Speaker 3: those valleys.
[21:05] Speaker 2: Hold on, I have to push back here. Space is
[21:07] Speaker 2: a cosmic shooting gallery. Everything is battered. Our moon is
[21:10] Speaker 2: saturated with craters. Why is this alternative theory so special?
[21:14] Speaker 2: If I take a baseball bat to a lump of clay,
[21:16] Speaker 2: it gets indented. What's unique about NISA?
[21:19] Speaker 3: Do understand why? It's just as wild as the trinary hypothesis.
[21:22] Speaker 3: We have to talk about the physics of impact cratering
[21:25] Speaker 3: versus catastrophic disruption. It is a question of scale and
[21:28] Speaker 3: structural integrity. Okay, explain that a standard impact creator is localized.
[21:32] Speaker 3: A small rockets a bigger rock excavates a bowl shaped
[21:35] Speaker 3: depression and leaves a scar. We see millions of those,
[21:38] Speaker 3: but we are observing continuous valleys wrapping around the entire
[21:41] Speaker 3: circumference of.
[21:41] Speaker 2: NYSA like someone tied a steel cable around a block
[21:44] Speaker 2: of cheese and pulled it tight precisely.
[21:47] Speaker 3: To create a continuous circumferential feature. Like that, you aren't
[21:50] Speaker 3: getting hit by small metiaites. You are talking about cataclysmic
[21:54] Speaker 3: collisions transferring incomprehensible amounts of kinetic energy.
[21:58] Speaker 2: Because Nissa is seventy five colometers across, it's the size
[22:01] Speaker 2: of a major metropolitan city.
[22:03] Speaker 3: If it is a solid rock, the sheer amount of
[22:06] Speaker 3: impact excavation required to carve those massive valleys without blowing
[22:10] Speaker 3: the entire seventy five kilometer asteroid into microscopic dust. That
[22:14] Speaker 3: survival story would be a scientific first.
[22:17] Speaker 2: Ah, it's the survival aspect. The laws of physics dictate
[22:21] Speaker 2: that the energy transfer should have shattered the entire rock.
[22:24] Speaker 3: In planetary mechanics, there's a threshold called the catastrophic disruption threshold.
[22:30] Speaker 3: If the shockwave from an impact exceeds the internal tensile
[22:33] Speaker 3: strength of the rock, the whole object shatters into a
[22:36] Speaker 3: swarm of debris.
[22:37] Speaker 2: So to carve a deep valley without surpassing that threshold.
[22:41] Speaker 3: The Goldilock's nature of those impacts would be statistically astonishing.
[22:45] Speaker 3: The impactors would have to be exactly big enough to
[22:47] Speaker 3: carve the valley, but not one fraction of a jewel
[22:49] Speaker 3: more energetic, or the whole thing is destroyed.
[22:52] Speaker 2: So either Nisa is an impossibly gentle three way merger,
[22:55] Speaker 2: or it is the ultimate survivor of impossibly precise kinetic hams.
[23:00] Speaker 3: Exactly. Both realities are highly improbable.
[23:03] Speaker 2: So how do we solve a visual puzzle when the
[23:06] Speaker 2: image intrinsically supports two completely wild contradictory interpretations. We stop
[23:11] Speaker 2: looking at the rock and we look right next to.
[23:13] Speaker 3: It, which is where the observational paradigm shifted entirely.
[23:16] Speaker 2: Yes, the tiny witness and the glare. I love this part.
[23:19] Speaker 3: While using adaptive optics to study the shape, Minker's team
[23:22] Speaker 3: was simultaneously employing a completely different set of imaging techniques.
[23:27] Speaker 3: They used high contrast imaging protocols originally developed for hunting
[23:31] Speaker 3: exoplanets around other stars.
[23:33] Speaker 2: That is a brilliant cross disciplinary hack. Usually you use
[23:37] Speaker 2: that to block out a star light years away to
[23:39] Speaker 2: see a tiny planet. Like standing in New York and
[23:41] Speaker 2: trying to spot a firefly around a searchlight in Boston.
[23:44] Speaker 3: That's the exact challenge. The stars glare hides everything. But
[23:47] Speaker 3: they took this exoplanet tech and aimed it at our
[23:50] Speaker 3: own asteroid belt.
[23:51] Speaker 2: Because NISA is so bright, it acts like a searchlight itself.
[23:55] Speaker 3: Exactly, any small object near it will be completely lost
[23:58] Speaker 3: in the intense glare of Nissa's reflected light. If you
[24:01] Speaker 3: used standard techniques, the pixels on the sensor would just saturate.
[24:05] Speaker 2: So they utilized an instrument called a coronagraph. What is
[24:08] Speaker 2: that physically, It is.
[24:09] Speaker 3: An opti mechanical device invented by Bernard Lyo in the
[24:13] Speaker 3: nineteen thirties. It places a tiny, opaque physical mask in
[24:17] Speaker 3: the focal plane of the telescope, perfectly aligned to cover
[24:20] Speaker 3: up the bright central object.
[24:22] Speaker 2: But light is a wave, so it bends around the
[24:24] Speaker 2: mask right right.
[24:25] Speaker 3: It diffracts. So a chronograph also employs secondary masks and
[24:29] Speaker 3: complex algorithms to suppress that diffracted light. It creates a
[24:32] Speaker 3: localized artificial eclipse inside the telescope itself.
[24:35] Speaker 2: And by creating that artificial eclipse, they suppressed the glare
[24:39] Speaker 2: of the seventy five kilometer main asteroid, and they found
[24:41] Speaker 2: a tiny, faint speck of light. They found a moon, a.
[24:45] Speaker 3: Distinct satellite orbiting Nissa, and it is absolutely tiny. It's
[24:48] Speaker 3: estimated to be only about one kilometer across.
[24:51] Speaker 2: A one kilometer moon orbiting is seventy five kilometer asteroid, and.
[24:55] Speaker 3: It orbits at a distance of at least one hundred
[24:57] Speaker 3: and seventy kilometers away from the center of nissa's officially
[25:00] Speaker 3: designated S twenty twenty six forty four.
[25:03] Speaker 2: And they had to spot it independently in two separate
[25:06] Speaker 2: observing runs to confirm it wasn't just a cosmic ray
[25:09] Speaker 2: or a glitch. Right.
[25:11] Speaker 3: Yes, in astronomy, you can never trust a single observation
[25:15] Speaker 3: at the bleeding edge of a telescope's capabilities.
[25:17] Speaker 2: I just marvel at the tech required to see a
[25:19] Speaker 2: one kilometer rock from hundreds of millions of miles away
[25:22] Speaker 2: while blocking out a blinding glare next to it.
[25:25] Speaker 3: What's fascinating here is that while the technological feet is incredible,
[25:29] Speaker 3: the actual existence of the Moon isn't shocking to planetary
[25:32] Speaker 3: scientists anymore. Small asteroids having moons is actually quite common.
[25:36] Speaker 2: That always surprises people. We intuitively think moons are reserved
[25:40] Speaker 2: for massive planets like Jupiter or Earth.
[25:42] Speaker 3: It requires a shift in perspective gravity scales with mass.
[25:46] Speaker 3: Look at the asteroid Dinkinesh. In twenty twenty three, NASA's
[25:49] Speaker 3: Lucy spacecraft flew past it. Deaconsh is only seven hundred
[25:53] Speaker 3: meters across, but it had a tiny satellite orbiting it
[25:56] Speaker 3: named CELM and.
[25:57] Speaker 2: Selom turned out to be a contact binary itself.
[26:00] Speaker 3: Exactly two smaller lobes stuck together orbiting a larger rock.
[26:03] Speaker 3: The asteroid belt is a highly dynamic gravitational environment.
[26:06] Speaker 2: But finding a one kilometer moon near NASA is more
[26:10] Speaker 2: than just cool trivia. It is the ultimate key to
[26:13] Speaker 2: solving the mystery of Niss's three lobes.
[26:16] Speaker 3: Yes, because a moon is a continuously running physics experiment,
[26:20] Speaker 3: it provides the mathematical key to calculate the fundamental properties
[26:24] Speaker 3: of its parent body.
[26:25] Speaker 2: So what does this all mean? How does a one
[26:27] Speaker 2: kilometer speck of rock tell you what the main asteroid
[26:30] Speaker 2: is made of?
[26:31] Speaker 3: It fundamentally revolves around density, and to calculate density you
[26:35] Speaker 3: need volume and mass.
[26:37] Speaker 2: Volume we have securely in hand from the Hires adaptive
[26:40] Speaker 2: optics images. We mapped the three D shape so we
[26:42] Speaker 2: can calculate the physical space it occupies.
[26:45] Speaker 3: But mass is vastly more difficult. Visual size does not
[26:48] Speaker 3: equal mass. A party balloon and a solid iron cannonball
[26:52] Speaker 3: can have the exact same volume but vastly different masses.
[26:55] Speaker 2: You can just weigh an asteroid on a cosmic.
[26:57] Speaker 3: Scale, but nature provides a scale for you, provided you
[27:00] Speaker 3: have a moon. Thanks to Johannes Kepler and Isaac Newton,
[27:03] Speaker 3: we have the tools. The orbit of a moon is
[27:05] Speaker 3: dictated entirely by the gravitational pull of the parent object.
[27:09] Speaker 2: And the strength of that pole is dictated by mass.
[27:11] Speaker 3: Exactly, by watching that tiny one kilometer moon trace its path,
[27:16] Speaker 3: measuring how fast it moves and how far away it is,
[27:18] Speaker 3: you can calculate the exact gravitational pole required to keep
[27:22] Speaker 3: it in orbit.
[27:22] Speaker 2: You plug those numbers into Kepler's laws, do the algebra,
[27:26] Speaker 2: and the precise mass of NISA drops right out.
[27:29] Speaker 3: Then you divide that mass by the volume from the images,
[27:32] Speaker 3: and you get the asteroid's bulk density.
[27:35] Speaker 2: And why does density solve the debate?
[27:37] Speaker 3: Because density physically distinguishes a loose pile of disconnected rubble
[27:41] Speaker 3: from a solid, coherent shard of rock.
[27:44] Speaker 2: Let's break that down. If the contact trinary hypothesis is true,
[27:48] Speaker 2: if it's three separate pieces resting against each.
[27:50] Speaker 3: Other, the resulting structure is not a solid block. The
[27:53] Speaker 3: bulbous lobes don't fit perfectly flush. There are massive empty spaces,
[27:58] Speaker 3: huge internal voids. At the interface is where they touch.
[28:00] Speaker 2: Like a glass filled with large ice cubes huge gaps
[28:03] Speaker 2: of air between them.
[28:04] Speaker 3: We call that macroporosity. Because a huge percentage of its
[28:08] Speaker 3: volume is empty space, its overall mass will be low
[28:11] Speaker 3: relative to its size, the calculated bulk density will be
[28:15] Speaker 3: very low.
[28:15] Speaker 2: But if the alternative is true, if it's a single
[28:18] Speaker 2: battered monolith.
[28:19] Speaker 3: A monolith does not have those massive structural voids, its
[28:22] Speaker 3: solid rock through its core, its mass relative to its
[28:26] Speaker 3: volume will be high, the calculated density will be high.
[28:30] Speaker 2: It's an incredibly elegant scientific resolution. The debate won't be
[28:34] Speaker 2: settled by the groundbreaking images that started it, but by
[28:37] Speaker 2: the pure math provided by that tiny speck of light.
[28:41] Speaker 3: It's a beautiful synthesis of different branches of astronomy. The
[28:44] Speaker 3: imaging gives you the structural question, the classical orbital dynamics
[28:48] Speaker 3: gives you the definitive answer.
[28:49] Speaker 2: You now understand how astronomers weigh an asteroid without ever
[28:52] Speaker 2: touching it, but zooming out, Why does Minker's team care
[28:55] Speaker 2: so deeply about the density of one specific asteroid.
[29:00] Speaker 3: If we connect this to the bigger picture, we have
[29:02] Speaker 3: to look back at that E type designation.
[29:04] Speaker 2: In state type the bright reflective material.
[29:07] Speaker 3: It only forms under very precise conditions, extremely high temperatures
[29:11] Speaker 3: and a lack of oxygen. When geochemists study and state
[29:15] Speaker 3: aite meteorites that have fallen to Earth, they analyze their
[29:18] Speaker 3: isotopic ratios.
[29:19] Speaker 2: What do they find?
[29:20] Speaker 3: The chemical and isotopic makeup of these meteorites is remarkably
[29:24] Speaker 3: almost identically similar to the isotopic composition of the Earth's mantle.
[29:27] Speaker 2: Wait, really, the exact chemical signature of NISA matches the
[29:31] Speaker 2: rock deep beneath our.
[29:33] Speaker 3: Feet to a startling degree. This leads sientists to conclude
[29:36] Speaker 3: that E type asteroids are likely the pristine source material
[29:39] Speaker 3: from the very inner region of the primordial solar nebula.
[29:43] Speaker 3: They formed in the exact same hot, chaotic neighborhood where
[29:47] Speaker 3: Earth was actively accreting.
[29:49] Speaker 2: So NISA is family. It's a direct cousin to the
[29:51] Speaker 2: material that built our home planet.
[29:53] Speaker 3: E types represent either primitive building blocks that never manage
[29:57] Speaker 3: to grow into a planet, or they are shattered fragment
[30:00] Speaker 3: of the crust of some early planetary body that was
[30:02] Speaker 3: destroyed in the cataclysmic collision.
[30:04] Speaker 2: We are looking at a seventy five kilometer piece of
[30:07] Speaker 2: debris to reverse engineer a process that happened billions of
[30:11] Speaker 2: years ago exactly.
[30:12] Speaker 3: If the math proves it has a low density, it
[30:15] Speaker 3: tells us gentle, low velocity accretion was a viable force
[30:18] Speaker 3: for building larger bodies. If it has a high density,
[30:21] Speaker 3: it tells us a story about the extreme violence of
[30:23] Speaker 3: planetary scale collisions.
[30:25] Speaker 2: The sheer scale of time involved is dizzying. We went
[30:28] Speaker 2: from a century of blurry frustration to using adaptive optics
[30:33] Speaker 2: to reveal a potential three lobed structure.
[30:35] Speaker 3: And then pivoting to coronagraphs to find a one kilometer
[30:39] Speaker 3: moon holding the mathematical key to the Solar System's origins.
[30:43] Speaker 2: It's a phenomenal detective story. And as we wrap up
[30:46] Speaker 2: this journey, I want to leave you with a slightly
[30:48] Speaker 2: unsettling thought to mulover. If Nysa is indeed a contact trainary,
[30:53] Speaker 2: a gentle amalgamation of primitive building blocks that survived the
[30:56] Speaker 2: chaos of the early Solar System. Consider the solidund beneath
[31:00] Speaker 2: your feet right now.
[31:01] Speaker 3: It changes your perspective.
[31:03] Speaker 2: What if the very foundations of Earth started exactly like Nysa,
[31:06] Speaker 2: Endless fields of bizarre, lumpy, multi loaded snowmen drifting silently
[31:11] Speaker 2: in the dark slowly sticking together over eons until they
[31:15] Speaker 2: forged a world capable of looking back up at the stars.
[31:17] Speaker 3: It's a powerful image.
[31:18] Speaker 2: Thank you for joining this conversation. Keep looking up and
[31:21] Speaker 2: keep questioning the shape of things

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