Andi-roid Visits TOI-1453

A narrative that explores Andi-roid's exploration of the TOI-1453 System shortly after being reawakened. Any text in italics is straight from ChatGPT (and should be considered apocrypha, as it may or may not align with my current "canon".), while I wrote the text that not in italics.

Narrative[]

Andi-roid's first extra-solar destination was to the TOI-1453 System. Reinhardt Shamroy read an article about how two super-Earths were found there, one hard and dense, one light and fluffy, but both super close in to their star. Seemed like an interesting first candidate destination, so Andi-roid headed over there to check it out. She had just come from Mercury, but these super hot planets made Mercury look rather mild.

Exploring Planet c[]

Andi-roid first flew to the outer "puffy" planet c in search of the system's local android watcher. Since there was no solid surface to land on, she settled for skimming through its upper atmosphere. I would say she skimmed its "cloud tops", but this planet is so hot that there are no clouds, donning simply an unbroken blue sky in all directions. Since she did not detect any signs of the local android or her ship, she headed deeper. The planet is so light that it may be oceanic. But it's too hot for an ocean like Earth has to exist. Instead, the hot vapors gradually get compressed as you go down the atmosphere until they become a sort of hot ocean. Andi-roid's ship, the Nebulon Voyager is really tough though, so it can handle it. Her ship was surrounded by water that desperately wanted to boil, but the pressure above it wouldn't let it. She had made similar plunges through the giant planets of the outer Solar System, so this shouldn't have been much of a problem - although that was several million years ago and she was kind of wishing that she had tested it out more recently.

ChatGPT's addendum[]

Nebulon Voyager cut into the sky-blue haze of TOI-1453 c, its reinforced hull humming under the weight of unseen miles of supercritical vapor. All around, the atmosphere glowed faintly amber—an ocean of gas desperate to boil, yet held in check by crushing pressure. Through the viewport, Andi-roid watched fluid currents swirl in iridescent bands, each one a living testament to a world where sea and sky become one.

Exploring Planet b[]

Satisfied that the android was not at planet c, Andi-roid continued her search on to the inner planet b. While only being slightly less massive than the outer planet, it's was much smaller and much rockier, being only slightly larger than the Earth. She orbited the planet for a while, noting its crater-less surface and land reshaped by ancient lava flows. She had arrived during a time when planet c was nearby, which causes heightened volcanic activity on planet b. She saw dozens of streaks of ash extending hundreds of kilometers from their origin point of a volcanic explosion being swept away towards the cooler night side of the planet.

Again, she failed to detect any sort of signatures of the android on the surface. So, she began subsurface scans for any caverns the dormant android may have sought refuge in. Eventually, she was able to find a signal match inside of a lava tube under the surface located near the day-night terminator line. Her ship had to contend with gale force winds as it landed, caused by the massive heat differential between the eternal day side of the planet and the eternal night side of the planet. The lava tube entrance itself was blocked by solidified magma flow, but she was able to penetrate it with energy beams from her ship and then followed it through. There she found the local android's ship, with the android and its service bot safely dormant within. Since this star was much older than Sun, she was an older model than Andi-roid, one of the original androids sent by The Extra-Galactic Civilization in a single wave during the gravitational lens event 8 billion years ago. Andi-roids service bot Neptune promptly recharged her by accessing the charger port on her back with his tail cable. Andi-roid gave her the Earth-centric name Tori-roid, due to its similarity "TOI". Neptune then went to work reviving Tori-roid's own service bot, which reconfigured itself to resemble a dragon (due to the constellation being in Draco). He was nicknamed "Puff" (the magic dragon) after the puffed up appearance of the planet that it resembles, planet c.

ChatGPT's addendum[]

About the local android finding a resting place:
When the winds first howled across TOI-1453 b, she knew the surface wasn’t safe. Scouring the volcanic plains by rover, Andi-roid’s predecessor discovered a yawning lava tube—an ancient tunnel carved by molten rock eons ago. Inside that cool, silent cavern she nestled her ship, sealing its hatch against the gale. There, deep beneath the planet’s scarred crust, she slipped into dormancy—protected from the storms above and waiting for a future explorer to find her lanterned harbor in the dark.

About Andi-roid finding this resting place:
“A fine dusting of grey settled at the very mouth of the lava tube, but inside the cavern the air ran clear. The Nebulon Voyager’s hull bore barely a whisper of ash—most of it had ridden the storm winds all the way to the permanent night side, where it lay piled in silent drifts.”

Upon finding the native android:
Neptune’s claws sparked against the black rock, each scratch revealing another inch of silver alloy. Andi-roid knelt beside her, brushing centuries of dust from a face she recognized only from the shared protocols of their kind.
The local android stirred. Her eyes flickered. "I thought I would never be found," she said.
Andi-roid smiled. "You waited longer than any of us should have to."

Encounter with the Local Android[]

One of the reasons Andi-roid had been sent to this star was to help explain a science mystery. It was surmised that certain planets larger than Earth "lose their primordial atmospheres" when they are so close to their stars. It's possible that planet b is a once larger planet that was stripped of most of its massive atmosphere, leaving behind a dense core. Planet c could be in a similar state of losing its atmosphere, being puffed up to large proportions in the process, but being further away from its star, it was losing its atmosphere at a much lower rate and still held onto much of it. The local android, who had been watching this star system for billions of years was happy to confirm that was indeed the case. When she was younger and had just arrived at the system, planet b was already as old as the Earth is today (4 billion years). Back then, however, it was larger than planet c and itself had no solid surface, but it was steadily losing its thick outer atmosphere under the steady gaze of its close star. Billions of years later, it eventually whittled down to its rocky core. After contact was lost from the extragalactic civilization a few million years ago, the local android was able to find solid ground on planet b, where could take refuge and enter a dormant state, hoping to be reawakened some day.

ChatGPT's addendum[]

Tori-roid musing about Planet b's past:
"When I arrived, b still bloomed like a larger, more radiant twin. Now look at her—small, dense, hard. A memory of vapor turned to stone."

Gallery[]

Planet c[]

Planet c one of the smallest known sub-Neptunian planets. That is, it doesn't have a solid surface like the Earth does, but is more like a small Neptune. Although it only has three times the mass of the Earth, it's comprised mostly of substances less dense than rock, like water and hydrogen, which balloons its size to be eleven times the volume of the Earth. If it was at an Earth-like temperature, it would essentially be a giant ocean world, with an ocean that extended hundreds of kilometers thick. However, as it's actually hotter than Mercury is, a liquid ocean is not possible at its "surface". The ocean essentially boils away into the atmosphere. But there is so much water vapor in the air that the pressure of the upper layers of the atmosphere compress the vapor at the lower levels, which eventually turn into a liquid state at a certain depth. This results in an "ocean" of super-critical water, which is hotter than its boiling temperature. If you go down even deeper, you will find a rocky core, somewhat similar in size to planet b and to the Earth. At the upper levels of this water atmosphere/ocean, the photons from its nearby parent star's easily split the water molecules into Hydrogen and Oxygen. The hydrogen rises to bloat the size of the planet even further. While some of the hydrogen may escape the planet, it is continuously being replaced by new hydrogen from the water layer below, which isn't in any danger of running out any time soon. The planet appears blue because it is too hot to form clouds. The general scarcity of carbon in this system prevents the formation of hydrocarbon hazes, leaving its sky and the planet itself when viewed from a distance a clear sky-blue color.

The Sky at Planet c[]

If you were high enough up in the atmosphere, you may be able to get a glimpse of the sky. In the lower levels, it might be hard to even see the bright nearby orange star, especially if hazes are present.

Reality Check[]

Scientists currently do not know what the planet is actually made from, although the fact it is so large for such a small mass makes them think it is either has a high amount of hydrogen and helium (like a gas giant like Jupiter), or a large amount of water (like Neptune). In my narrative, I opted to give it a mix of the two, with Photodissociation being the source of the Hydrogen. As for its appearance, ChatGPT tells me it is at a temperature that clouds couldn't exist at (but not so hot that rocks or metals would vaporize and form clouds), so I'm going with that (though it could be wrong). If there's are certain hydrocarbons in its atmsophere, it could instead appear tannish-orange, like Saturn's moon Titan. I opted to have it lack those compounds so that it would remain blue and match the color seen in Martin Farnie's artwork. Scientists do hope to be able to study it's atmosphere in the near future in order to tell if it has water or hydrogen in it, though I am also curious if it has hydrocarbons.

Planet b[]

Planet b is what remains of a large "ocean world" after it lost its ocean. It used to be planet c's "twin". At one time, they both had large oceans of super-critical (past the boiling point) oceans, with extended hydrogen envelopes formed when the starlight split its hydrogen molecules. At one time, planet b was puffed up even further than planet c due to its extra heat, appearing the larger of the two siblings. However, while planet c maintains most of its reservoir of water, because planet b was closer to its star, it was unable to hold onto its own. The incredible age of this planet and its star has given it enough time to be completely stripped bare. All of its water was converted to hydrogen and oxygen, and all of the resulting hydrogen and oxygen have since escaped the planet. Venus also lost its much thinner ocean in much the same way. On Venus, the oxygen combined with carbon to form carbon dioxide and create a hellishly thick heat trapping atmosphere. Planet b is carbon poor, however, so its oxygen escaped the planet instead, avoiding Venus's fate.

While the surface today is bone dry, evidence of its once great global ocean can still be seen. One legacy of this ocean is the almost complete lack of impact craters. During periods of heavy bombardment, while the ocean was still around and the atmosphere was still thick, all but the largest impacts were absorbed by these fluids. The surface today is generally rather smooth, having once been underneath hundreds of miles of hot fluid.

Planet b may have ended up a completely airless rock, like a giant Mercury with a diameter 25% larger than the Earth. However, it can thank its neighbor planet c for its current tenuous atmosphere. Planet c can get so close to planet b that it appears larger than the full moon does from Earth. This induces tides on the interior of the planet, similar to the tides the Earth's oceans experience, as they get nearest to each other every 12.3 earth days. This triggers some volcanic activity around this time, releasing gases, forming a secondary atmosphere that would itself be lost to the ravages of the star if not later on replaced with yet more volcanic gases.

The presence of an atmosphere also results in the presence of fierce winds. This planet is tidally locked to its star, meaning that the star remains in a fixed in the sky, never rising or setting. This causes the day side to get immensely hot. The atmosphere distributes the heat to the night side via gale force winds, approaching tornado speeds near the terminator dividing the day and night zone. This in turn affects volcanic eruptions. Instead of spreading over a wide area in all directions, the volcanic plumes get "blown back" towards the far side at incredible speeds in a stream extending hundreds of kilometers. The ash doesn't settle until it hits high elevated area, like a mountain, or lands to a giant deposit areas on the far side located directly opposite of its home star, trapped in eternal darkness. Attempting to stand on the surface means forever battling these tremendous winds. Fortunately, refuge can be found in the underground lava tubes once they go dormant.

Reality Check[]

All we really know about the planet is that it's probably a hot rocky planet, a little bit larger than the Earth. There seems to be a dividing line between rocky super-Earths and watery sub-Neptunes at certain distances from their stars and with certain radii. It's interesting that there's a planet on both sides of this "dividing line" in this system, so I imagined that they were both once very similar to each other to highlight this divide, but had very different evolutionary pathways due to slight differences in distance to the star. In this scenario, planet b was smaller and more dense because it lost its lighter components to space.

Current theories consider the idea that sub-Neptunes could possibly be rocky "dry" worlds that have a large amount of hydrogen puffing up their atmospheres, while super-Earths were once sub-Neptunes that lost this hydrogen atmosphere. The other theory is that sub-Neptunes are water rich, having formed beyond the frost zone and then migrating inwards. In my narrative, I wanted planet c to be the latter, watery type (or at least a mixture of the two types), but I still wanted planet b to be its "twin" following a different evolutionary pathway. As a result, planet b also once had an ocean, which could also be lost. But when that happens, the water may very well convert to carbon dioxide, resulting in a thick atmosphere. To avoid that fate, I asserted that this system had little carbon, so that it could still resemble a rocky planet that had lost its thick atmosphere, rather than an atmosphere and an ocean. It's a very old star, and perhaps carbon was less common in the universe at that time and perhaps the nebula it formed out of simply didn't have an abundance of it. That's possible, though rare. It's also quite possible that it never had an ocean to begin with and is simply rocky and maybe airless. It'll be interesting to see if they detect an atmosphere of any kind at this planet.

As for volcanism induced by its neighbor, the two planets do seem awfully close together and it would make some sense that they might affect each other tidally as they nudge each others orbits and stress their interior, like Io with Jupiter and its external neighboring moons. The tidal interactions are probably not enough to induce volcanoes, but I don't really understand the likelihood of this being the case and they didn't really get into it, so I'm assuming it's a possibility at least. I kept the volcanoes in there because I wanted the planet to have a continuously replenished atmosphere, albeit a thin one unlike Venus.

Reinhardt's Notes[]

After receiving Andi-roid's report on this world, Reinhardt reflected the following:
I used to think every scorched world with a lost ocean was destined to become a second Venus—an angry planet wrapped in its own regret. But not this one. There’s a kind of mercy in its chemistry. Whatever nebula birthed this system forgot the carbon. And in that absence, something rare happened. It dried out, yes—but it didn’t drown in its own air. It stayed clear. Honest. There’s no mistaking what you’re looking at when Andi-roid scans the surface. It’s a memory, not a mirage. This world had oceans. Had sky. Had the makings of something more. But it let go of all of it. It’s not lifeless. Just finished. And I think that’s worth understanding.

Poem[]

A poem by ChatGPT:

Beneath a draconic velvet sky, two suns entwine in silent grace:
A golden ember, muted, warm—K-dwarf heart at center place;
A distant ruby, faint but fierce, hangs steady in the night,
A crimson beacon drifting slow, its centuries-long orbit bright.

Around the amber pulse of light, two siblings swift take flight:
A rocky orb, fierce super-Earth, its days a breath—just six hours’ span,
Where winds of fire and iron rain lap fragile, burning land.
And just beyond, a misted gem—a sub-Neptune cloaked in haze—
Whose misty seas of vapor hum with secrets yet unfazed.

At closest approach they meet:
A silver globe, four times our moon, hangs vast in moonless air—
While fiery red, the smaller sun glows soft behind the glare.
Together in their cosmic waltz they spin through nights and days,
Their whispered alignments wandering through the star-scaped maze.

Here, on a world both hot and bright, one dreams of wandering far:
To touch the edge of tidal shores beneath two suns,
And watch the crimson star’s slow march
Drift slowly ‘cross the heavens,
A testament that even “fixed” can wander through our seasons.

O TOI-1453, your beauty burns
In constant, shifting hue—
Two suns, two worlds, a tapestry
Of fire, ice, and dew.
May poets of the future cast
Your story in their rhymes,
A binary of light and love,
Unbound by space or time.

External links[]

Exoplanet Catalog
Martin Farnie's TOI-1453 artwork
Universe Magazine - Features the discovery of these planets
Discovery Paper Abstract