Test of Mettle (A Captain's Crucible Book 2) (25 page)

The
Callaway
and her escorts were running under minimal power, letting momentum and gravity carry them on their current course. They flew close together in a long chain so that their thermal signatures overlapped and blended; thanks to the hull heating caused by their proximity to the stars, to enemy sensors it would appear they were a single vessel. That was the hope, anyway.

In the past, the enemy had often concentrated their forces on the smaller, easier targets. But the captain felt the aliens would change that behavior, at least for the current battle, because they knew Jonathan was expecting that. As such, he was betting that the enemy would believe he had dispatched one of his vessels as a decoy—a smaller, easier target meant to draw them and lead them astray from the other six friendlies four hundred thousand kilometers away.

He hoped at least some of the enemy forces would break formation to pursue those six signatures. With luck, the majority would. And then when the remainder came upon the so-called lone vessel, perhaps expecting an easy victory, they would discover that it was not one warship after all.

Ten minutes later:

“External temperature nine hundred degrees Kelvin, starboard side,” Lewis announced. “Alien fleet has closed to the four hundred fifty thousand kilometer mark. Blue main sequence star has passed below the horizon of the subgiant.”

Jonathan glanced at the video display on his aReal. Sure enough, he could no longer see the main sequence star, but the edges of its accretion cloud were still visible near the subgiant’s corona. The interference caused by energetic protons on the video feed had worsened, however, likely due to the
Callaway’s
closer proximity to the subgiant.

“Radiation levels?” Jonathan asked

“Still relatively moderate,” the ensign answered. “I’m recording the highest exposure levels in the breached mess hall two, at five mSv per minute.” Even though the entire port side was facing away from the sun, the ship would still be passing through radiation belts, allowing ionizing particles to enter through the breaches. “The rest of the ship is averaging 0.5 mSv per minute.”

Jonathan wasn’t sure whether to call that moderate or high. For comparison, each crew member was normally exposed to 0.5 mSv
per week
.

The captain focused on the tactical display.

“Any sign of alien ships breaking away to pursue the six friendlies?” Jonathan asked.

“Negative, sir,” the ensign responded.

Ten more minutes:

“External temperature nine hundred fifty degrees,” Lewis said. “Alien fleet has reached the four hundred thousand kilometer mark.”

Jonathan stared at the display, willing at least some of the enemy vessels to divert course and give chase to the other six.

“They’re not going to fall for it,” Miko said.

“They will,” Jonathan said between gritted teeth. He clasped his hands and steepled the index fingers. He tapped his lips.

They have to.

A
moment later the magic moment happened. Jonathan watched as a full fifteen of the dots representing the enemy vessels began to break formation, moving toward the six friendlies.

“Captain—” Lewis began.

“I see it,” Jonathan interrupted.

“Almost half the fleet. That’s better than I hoped for.” Jonathan noted with some relief that the prison ship T300 wasn’t among the group headed toward the six friendlies.

As the minutes passed, he watched as the divergence between the alien task units became more pronounced, until the computer labeled them ETU1 and ETU2: Enemy Task Unit One and Two. ETU2 was the diverging group, while ETU1 continued after the
Callaway
.

Several minutes later the first enemy task unit had reached the two hundred thousand kilometer mark behind them. Thanks to the increased acceleration provided by their current trajectory, the six friendlies were almost a million and a half kilometers away by then. The second task unit was four hundred and fifty thousand kilometers behind those friendlies, also thanks to the increased acceleration. Both were barely visible above the horizon of the nearby subgiant. The blue main sequence star was still gone, hidden behind that same horizon, though a portion of the accretion disk remained visible. From the point of view of the friendlies and enemy task unit two, however, that main sequence star would be quite visible.

“What’s the ETA on the reactors and mortars we fired at the main sequence star ten hours ago?”

“The debris from the reactors and mortars, you mean?” Ensign Lewis asked.

Every warship had agreed to launch at least one of their reactor cores into the void. The process involved carefully turning the nose of each ship with the help of the AIs so that the ejected cores would follow the necessary trajectory. The slowest ships in the fleet, the
Grimm
and
Marley
, had been allowed to keep their cores, because Jonathan was unwilling to reduce the maximum speed of the group to below seventy percent. Mortars had been launched as well, to provide the raw materials necessary to attain critical mass and pressure.

The reactors had broken up hours ago, due to the lack of heat shielding. The mortars had lasted longer, but as the rocks passed into the death zone, even they couldn’t withstand the tidal forces. However, the constituent parts had continued moving with their original speed and heading, and that was how the AI tracked them. Jonathan had hoped the incredible heat from the binary suns would mask the small thermal signatures from the enemy from launch to impact, and judging from the apparent success of the ruse, that seemed to be the case.

“Yes,” Jonathan said absently. “The debris from the reactors and mortars.”

“The lead portion should reach the accretion disk in five minutes,” Miko said. “Because of their relatively high speed, the elements should pass just above the major axis of most of the particles, drawing a swathe of plasma from the cloud along with them. A minute and a half after that, the particles should pass into the corona and chromosphere, before hitting the photosphere thirty seconds later. If successful, the resultant detonation will cause the flare to erupt microseconds after.”

Magnetic loops, called prominences, were distributed throughout the plasma of that sun. When those loops touched, the “short circuit” caused a solar eruption that led all the way to the surface, releasing a flare. It was hoped the detonation of the geronium inside the photosphere would cause such a short circuit by shoving one of those loops into another nearby.

“Will the second enemy task unit be close enough?” Jonathan asked.

“Most likely,” Miko said. “The calculations predict a massive energy outburst. As I said at the conference, if we’re lucky and hit a sunspot the energy release could be upwards of sixty billion petajoules. Your question should probably be, will
we
be
far
enough away?”

Sixty billion petajoules. In the conference, Miko had equated that to the detonation of roughly a hundred and sixty billion megatons of TNT. While it was perhaps an antiquated comparison, it suitably emphasized the incredible power of the flare.

“I thought that magnitude of energy release was confined to the surface of the star?” Jonathan asked.

“Well it is,” Miko agreed. “But not even Maxwell’s plasma dynamic algorithms can predict how far the resultant flare will reach, nor how much coronal mass will be ejected, if any, not with any degree of accuracy. But either way, even if those ships are hit with only a tenth of a percent of the surface energy, they’ll be vaporized.”

Jonathan nodded. Miko had already gone through all of that at the conference, but it was good to hear it again for confirmation. The hope was that the corona and loosely bound outer layers of the subgiant would shield the main human fleet from the high-speed protons, electrons, and heavier ions that the companion star’s flare would eject in copious quantities. Maxwell predicted that the outer layers of the subgiant would experience a sudden steep rise in temperature as the energy of the particles was absorbed and radiated into space, but that was the worst of it.

The nearer enemy task unit would be similarly spared, of course. But as for ETU2... like Miko said, they would be vaporized.

“The decoys are breaking up!” Ensign Lewis announced.

So the heat and tidal forces had finally proven too much. The six friendlies vanished from the display, their thermal signatures flaring out as the units broke apart in turn.

Those “friendlies” were actually a series of six 3D-printed heat shields, each one designed to mimic the signature of a different starship in the human fleet. The engineers had placed small, battery-powered emission sources at key spots on the shields. In preparing the unmanned objects, the team had taken into account how the signatures would look when heated by the radiation from the binary stars in order to give the most realistic approximation to their starship counterparts.

It had worked.

Up until that moment, anyway.

“The fifteen vessels of enemy unit two are issuing emergency deorbital burn,” Lewis stated.

“They’ve realized the ruse,” Robert said. “They’re trying to put as much distance as they can between themselves and the suns.”

“But they’re too late,” Jonathan said.

“Maybe,” Miko said. “Maybe not. We won’t be certain until the geronium achieves critical mass.”

“
If
it reaches critical mass,” Robert corrected.

“It will, Commander,” Jonathan said. He had resigned himself to assuming the role of the positive one in the pair, for the moment. “And even if the geronium doesn’t, those ships won’t be a threat for at least a few days while they loop around the binary stars, trying to escape the gravity.”

“But the fleet will still have to face them eventually,” Robert said.

Jonathan nodded. “And so we will.”

He checked the display. The nearer alien task unit had closed to one hundred seventy-five thousand kilometers. At some point he would have to order the human fleet to initiate deorbital burn itself, in order to determine their final trajectory in the slingshot maneuver that would take them around the subgiant. However, before doing that it was best to wait until the flare from the main sequence companion passed: he didn’t want to risk putting the fleet in the path of the relativistic electrons, protons and heavier ions surging from it.

“The lead portion of the debris has penetrated the accretion cloud,” Lewis said.

Jonathan waited tensely. He thrummed his fingers impatiently on the armrest.
Come on. Come on.

The predicted minute and a half that the particles would take to reach the chromosphere passed.

“The leading debris should be within the chromosphere,” the ensign said.

Jonathan thrummed his fingers louder.

The prerequisite thirty seconds the geronium should have taken to reach the photosphere transpired.

Still nothing happened.

“It should have reached the photosphere by now,” Robert said.

Jonathan stopped thrumming his fingers and instead wrapped his fingers tightly around the armrest instead.
Come on.

The leading geronium would have imparted most of its velocity and angular momentum to the surrounding gases as it penetrated the photosphere. When subsequent debris struck, it would impact with slightly more energy, plowing into the leading matter. The energy of each successive wave would continue to be slightly greater, and because of the intense temperature and pressure, as more of that geronium struck, in theory the pressure would build until critical mass was achieved....

“Maybe our calculations were off,” Miko said.

“My calculations were correct,” Maxwell said. “But luck and probabilities always factor into such a long distance throw. Maybe the accretion disk was heavier than our initial readings suggested, and slowed down the incoming debris too much. Maybe the particular surface area of the main sequence star where the debris struck has excellent convection properties, and dispersed the geronium as it came in. Maybe the magnetic loops in the star were too far apart for the geronium to cause a short circuit. There are so many factors that could have influenced the outcome.”

Jonathan waited several moments longer, then sighed. “Perhaps too many.” The first part of the strategy had failed.

He was about to give the order to begin deorbital burn when the external video feed became completely white.

“Ops, report!” he said. At first he thought the given external camera had burned out due to the EMP-like effect of charged particles interacting with its electronics, but in theory that shouldn’t be possible, not when shipboard instruments used the entire hull as a voltage ground. And if it had burned out, the display would be black, not white.

“Starboard hull temperature critical at five thousand Kelvin,” Lewis said urgently.

“Looks like our geronium achieved the necessary critical mass after all!” Robert said.

“Radiation levels?” Jonathan asked the ops station.

“High,” Lewis answered. “The ship is averaging one mSv per second, now. Or sixty mSv per minute. Though that’s still far below what we’d be hit with if we were above the subgiant’s horizon.”

So the outer layers of the subgiant were sparing them from the majority of the relativistic particles after all, and its surface was heating up massively in the process, though higher than Maxwell had predicted. Or perhaps the temperatures the fleet was experiencing came directly from the flare itself—while the temperatures could range anywhere between ten million and twenty million Kelvin inside the solar explosion, heat dissipated incredibly quickly in space, so it wouldn’t be unreasonable for some of the thermal radiation to reach the fleet at five thousand degrees. Even so, the enemy task unit two would likely be experiencing four times that temperature if they were lucky, and two thousand times that if they were not.

A streak of light appeared in Jonathan’s vision. It wasn’t caused by his aReal, but was likely the result of an energetic proton interacting with his optic nerve. So much for all that shielding. He was suddenly very glad for the subdermal patch he wore.

“Hull temperature five thousand
three hundred
Kelvin,” Lewis said.

“Helm, fire lateral thrusters,” the captain said. “Rotate our ventral section toward the star. Give the starboard heat armor a respite.”

“Aye Captain,” the helmsman said.

After the rotation was complete, the damaged port side would still face away from the sun, and the Avengers, mounted on the dorsal and port sides, would remain shielded from the heat and radiation.

Slowly, too slowly, the ship began to rotate. The bridge compartment shuddered in complaint.

A call from Stanley appeared on the captain’s aReal. He was reluctant to take it, because he knew what the chief engineer was going to say.

“What is it, Lieutenant Commander?” Jonathan said after accepting.

“What the hell are you doing to my ship up there?” Stanley screamed over the comm.

“I went over the briefing with you,” Jonathan said. “The subgiant was expected to heat up a bit.”

“A bit!” Stanley exclaimed. “Our hull is only rated to withstand a temperature of forty five hundred Kelvin... not fifty-three! And for
short
periods of time. Short! As in seconds!”

“We’re working on alleviating that,” Jonathan said.

“Hull temperature five thousand four
hundred Kelvin,” Lewis said.

“Damn it, Jon, move the ship to a higher orbit,” Stanley transmitted.

“You know as well as me that we’ll never be able to move to a higher orbit in time,” Jonathan said. “The Delta V costs are extremely high at the moment. In any case, I’m kind of busy at the moment. Captain out.”

He terminated the connection before Stanley could raise the inevitable objection.

The captain stared at the temperature reading on the display and held his breath as the ship continued to rotate all too slowly.

Jonathan clenched his jaw. “Natural flares never last this long.”