Cradle of the Sun

Cradle of the Sun is a 2018 science fiction novel by American writer James McLellan. Much of the story takes place around a neutron star whose magnetic poles are nearly aligned with the axis of rotation.

Cradle of the Sun
AuthorJames McLellan
Cover artistMaciej Rebisz
CountryUnited States
GenreSciene fiction
Publication date2018
Media typePrint and e-book
Preceded bySingularity
Followed byFirst Contact

2Plot Summary
3See Also


The Star

Most of the story occurs around an unnamed pulsar that has previously escaped detection. The magnetic poles of the pulsar are about 4 degrees off the axis of rotation, and radiative pressure streams from the cone in a beam about 6 degrees wide. These conditions create a region of constant radiation pressure. For diamagnetic materials, such as water, the repulsive forces of diamagnetic levitation and the attractive forces of gravity balance one another at a distance of 10 astronomical units from the pulsar's northern and southern poles. The strong center of radiation pulsing at a frequency of 10 hertz creates a pulse-width modulated conical fence that holds stellar material suspended just above the rotational poles. Cometary material, rocky material with a high pyrolytic carbon content, and strongly diamagnetic metallic material such as bismuth churn in semi-stable, but complex orbits completely inside the radiation cone.

Pulsar with overlapping radiation cone
Diagram of pulsar in Cradle of the Sun

A less exotic gas torus of material falls in an orbital plane nearly orthogonal to the unnamed pulsar's rotation. Within the gas cloud exists the remains of at least one rocky world.

Origin of Solar Heavy Matter

Part of the characters' interest in the star lies in their belief that the pulsar is the point-of-origin for heavy matter[1] and proteins [2] in the solar system. Heavy elements are created as byproducts of stellar fusion, and ejected when a star dies. Nevertheless, rocky bodies such as the Earth are evidence that the heavy material in the solar system did not originate inside the sun (which is still burning). Likewise, despite Earth widely being believed to be the origin of life, precursors to amino acids have been found in both asteroids and comets[2], suggesting an origin outside the solar system for both.


Life exists within the radiative region, adapted to utilize the plentiful radiation by some undescribed mechanism for biological processes, and consuming biomass in a food chain beginning on muddy water comets, just warm enough to be liquid as they pass through the inhabited region.

Plot summary

Plot setup

Robbie wakes up in an infirmary to discover he had been killed barely twenty-four hours ago in a comet mining[3][4] accident when his captain, rushing to finish a disappointing trip, ignores the advice of crew in a explosive blasting operation intended to make the icy 'berg'[4] balanced for transport back to Eris, a dwarf planet in the solar system about 80 AU from the sun, to be processed into mass energy. As a digital person, death is merely an inconvenience for Robbie. Nevertheless, his mining equipment, including a robotic space suit that he could upload into was ruined in the accident. Finding himself dispossessed, Robbie reaches out to his network of contacts and accepts an offer for a one-time trade venture with a friend.

The action picks up two years later. Robbie is returning to Eris from a visit to the regional economic center of Triton, a moon of Neptune. He is approached by a man identifying himself as Henry Curtis. Curtis is looking for his estranged brother Neville. Investigators hired by Henry to find George lost track of the younger Curtis brother at Hi'iaka, a moon of the dwarf planet Haumea. At about the same time, according to Henry's investigators, Robbie was selling goods to comet miners, and Henry Curtis had tracked down Robbie to enquire directly if Robbie had seen George, and if he had any clues he might share as to where George might have gone to next. Robbie indicates that he had met George, and that he'd been told by the captain that George had hired that they intended to go to Makemake at the edge of the solar system, trade all their possessions for fuel and leave the solar system entirely.

Robbie relates a story he'd been told, something of an urban legend among comet miners, about a hypothetical origin star system for most of the solar system's heavy metals[5] and complex proteins[6]. Among the community, such a find would be a treasure trove in the novel biotechnologies that miners presume could be gleaned from the proteins. Robbie relates that George's navigator had been drunk and, the night before they left, talked at length with anyone who would listen about the origin star. And, moreover, because the wife of another friend-in-common on George's crew had mentioned her husband intended to return from the voyage ridiculously rich.

Henry asks if Robbie believes the story. Robbie relates some of where he'd been told to look in the sky for this origin star. George's navigator had cross-referenced the general directions with star maps taken from humankinds first extra-solar colony[7] (Colony), about sixteen lightyears away[8], and higher in the galactic plane[9]. From the higher vantage point, the missing star was visible, and could be plotted on a map.

Henry reveals his intention to track his brother, and asks Robbie to come as a captain and consultant. Robbie turns him down, initially, but experiences a change of heart. The crew outfit for a trip that will either end in : the ship drifting out into space forever, trapped at their destination without resources to convert to the necessary fuel for a trip home, or after a sixty-six year round trip.

Plot conflict

The crew take turns sleeping and awake in a digital slumber, while the few flesh-and-blood crew members remain fully hibernated. Dimming of the stars caused by their entry into the gas torus tells Robbie and his crew of comet miners that they have reached their destination.

There is a struggle where to begin the search. The veteran crew want to immediately replenish their fuel reserves, guaranteeing that this would not be a one-way trip. Henry, however, wants to prioritize the search for his brother. They are both satisfied when they discover the unnamed pulsar holds water ice and other diamagentics suspended above the poles. Wishful thinking allows the crew and Henry to assume that George would think, like them, that inside this radiation region is the best place to fill his tanks and go exploring for novel proteins.

The crew put their trust in the substantial radiation shielding[10][11][12] they'd outfitted, and attempt to cross into the region, which requires being bathed in the full strength of the pulsar for at least a few minutes. The passage is terrifying, but survived. On the calm inside of the pulsar cone, thirty-three years of neglect of the cryo tanks causes the primary radiation shielding[13] to fail. Fearing how the antimatter fuel aboard might react to the magnetic extremes, the crew abandon ship, "falling" to a nearby comet that is accelerating into deeper space.

The ship survives, and the crew reclaim their vessel. They discover that this region doesn't carry just the remnants of pre-solar proteins, but an entire ecosystem has evolved to thrive in this peculiar environment.

Indigenous intelligent life take an interest in the ship. The creatures communicate with one another in the vacuum using 2.5 to 3 centimeter wavelength radio waves, roughly the size of a human voicebox[14]. The chatter is picked up by the ship's ultra high frequency (UHF) receiver. A mysterious piece of software makes it possible to translate the speech live.

Henry enquires about his brother. This police patrol doesn't know about any other strangers, but offer to take them to the capitol. The crew identifies that activity near the pulsar suggest it may soon become a magnetar[15], flooding nearby space with radiation. Time to find George and get out may be short.

At the capitol the crew discovers that the ruler is fickle and cruel. The crew barely escapes an immediate death sentence by feigning to be gods from the "Singing Star" (Sol), which the crew guesses "sings" due to UHF radio transmissions[16]. The crew further prove their godhood by a "demonstration" using mining explosives.

While the ruler tries to figure out what to do with them, they stay at the home one of the soldiers in the capitol. Robbie deduces that one of the crew is originally from pulsar. He confronts the crewman, who admits he was a refugee in a civil war nearly a hundred years passed. Him, and a few like him, had come to the solar system hoping the "songs" were another people like their own. They found a solar system hostile to life, as they knew it. The crewman had been copied into a digital person, as best as human technology was capable of doing, by the explorer who had found his near-lifeless body clinging to a comet.

Plot resolution

The crew seize on some of the local mythology and plot to overthrow the ruler. Some of the crew would prefer to make a run for deep space and take their chances on finding enough convertible mass-energy to get home.

At a celebration in honor of the ruler, the crew finally decides on civil war. Using the truth and mythology behind their refugee, the crew manages to convince s third of the military leaders to join them. Outnumbered, they make a stand in a mined-out rocky asteroid, before launching a surprise attack that topples the old ruler before his forces can fully muster.

The new rulers allow Robby and Henry to fill their stores with water, trinkets, biological samples, and as many stories as their datastores can hold.

Leaving the pulsar for home, they detect a trace of George - Henry's brother - conservatively working a comet far away from any danger posed by the pulsar. Henry and George have a happy reunion, and mend their relationship.