The spaceship's descent was not a vertical drop but a continuous spiral around Jupiter, gradually decreasing in altitude.
After detaching from the warship, the missiles flew in an arc around Jupiter, appearing vertical from the perspective of Expedition One but a curved trajectory from other directions.
Or rather, a parabolic arc.
The missiles coasted for over a million kilometers, only reigniting their engines when they neared the orbit of Callisto. They then shifted from a vertical dive to horizontal flight, launching a head-on assault from the moon's front.
The advantage of this approach was a higher relative speed between the missiles and the moon, making interception significantly more difficult.
In such a scenario, even the most brilliant tactics would struggle to be effective; true victory was an accumulation of small, incremental advantages.
From initial complete domination to later desperate struggles, the alien species had a tale to tell. They had long since shed any arrogance and no longer dared to underestimate humanity.
How could such a seemingly primitive civilization, barely venturing beyond its home planet, be so tenacious?
When Expedition One reached Jupiter, the alien species paid it considerable attention. Their earlier inaction was due to a lack of perceived necessity. As the missiles approached the lunar orbit and began their transition to horizontal flight, large swarms of ice-based alien fighters took to the skies.
Furthermore, the enemy had not only manufactured rudimentary fighters but also deployed over a dozen ice-based gunships and two ice-based warships, each no less than a hundred meters long.
Witnessing this scene, everyone was stunned.
What technology did the alien species employ to construct so many flying machines in such a short time?
Ou Zhanpeng even harbored a thought: could this be the alien species' trump card, reserved for dire emergencies?
Before any contact was made, swarms of missiles dispersed. The leading missiles detonated prematurely, releasing a wide smokescreen.
The enemy's aerial formations remained undeterred, seemingly prepared for this.
However, the human missiles within the smokescreen did not fly predictably; instead, they silently split, releasing sub-munitions.
In an instant, the number of sub-munitions exceeded two thousand. Only half were equipped with nuclear warheads; the rest were conventional.
The military's reserves were limited, and this was the result of a meticulous search, bringing out their entire stored inventory.
Expedition Two went even further: only one-third of the nuclear warheads were domestically produced; the remaining two-thirds were urgent reinforcements from Russia, the United States, and other allied nations.
Facing a common enemy, the Earth's allies had to set aside their differences, however significant. To prioritize self-interest or bargain at this juncture would be tantamount to self-destruction for humanity.
The over two thousand warheads, split into two groups within the smokescreen, saw half heading towards Callisto, while the other half remained on course for Jupiter.
The missiles that had launched their warheads were the first to break through the smokescreen, encountering the intercepting aerial formations, and the battlefield erupted in flashes of light.
The alien gunships unleashed peculiar white beams. Any missile struck by these beams immediately lost power and drifted solely on inertia.
Following this, swarms of alien fighters surged forward, systematically dismantling the missiles.
However, not all missiles were neutralized by the alien species. The next wave of missiles emerged from the smokescreen at extreme speed, targeting the gunships and warships.
Ghastly white beams and the brilliance of explosions filled the battlefield. Before long, dozens of alien fighters, six gunships, and one enemy warship were annihilated on the spot.
When another batch of missiles exited the smokescreen, the alien aerial formations were already decimated. The remaining aircraft, fighting with all their might, could not intercept many warheads. The sole remaining ice warship was struck by a nuclear missile and destroyed.
The remaining alien forces fought desperately. The moment they detected a missile, a squadron of fighters would swarm it, destroying one to replace another until the missile detonated.
Half an hour later, the battle neared its conclusion. Only three missiles managed to breach the blockade, but none hit their intended targets.
However, this was of no consequence, as humanity's true killer assets were the subsequent warheads. Devoid of propulsion and exhaust trails, they drifted silently in Callisto's orbit. Some even altered course, synchronizing their drift with a speed only slightly slower than Callisto's.
They would land successively in the near future, initiating continuous and unpredictable bombardments.
But no one was disappointed, as the focus of the lead ship had long shifted away from the battle. The warheads heading towards Jupiter were the true prize!
They had not veered off course. The trajectory and velocity of each warhead had been meticulously calculated. What appeared to be a chaotic mess was, in reality, anything but.
Under the influence of Jupiter's gravity, the warheads continuously accelerated, passing the orbits of Io, Europa, and Ganymede, finally breaching Jupiter's atmospheric outer layer and flying towards the planet's opposite side.
After executing a nearly ninety-degree turn, the more than a thousand warheads split into four groups, each heading towards Io, Europa, Ganymede, and Callisto, respectively.
This was no longer an awkward assault from behind the moon but a vertical strike from the planet's inner side outwards.
The essence of this plan was to alter the warheads' attack vector, thereby circumventing the disadvantages of a rear assault.
Within humanity's military doctrine, there were two methods for attacking from a moon's backside: one was a long-range detour, flying to the moon's side or below to launch the attack.
The advantage was simplicity and convenience; the drawback was significant speed loss and a less sudden attack, allowing the enemy ample time to intercept.
The second was a low-altitude flyby, launching the attack upon approaching the target, similar to cruise missiles.
The fleet employed this method when assaulting Mount Landing.
The advantages were a sudden attack and greater difficulty in defense; the drawback was the need to consider the celestial body's surface terrain and gravity, controlling speed within a certain range.
It was impossible to say which method was more reliable; one had to judge based on the actual battlefield conditions to determine the more suitable tactic.
It was somewhat ironic that humanity's space military power was of such recent origin, lacking any truly large-scale fleet engagements, with virtually zero practical combat experience.
Yet, every capable ally on Earth had been repeatedly exploring various space combat tactics through simulated engagements.
Simulated engagements were not mere theoretical discussions but exercises conducted in the most realistic manner after pre-setting battlefield conditions. Numerous simulated engagements had generated a series of space warfare theories, such as "Discourse on the Advantages of High Orbit," "Adverse Attack in Low Orbit," "Forward Evasion and Reverse Assault," and "Fundamental Principles of Space Combat," among others.
These theories bore a resemblance to aerial combat tactics, yet they were subtly different and not entirely identical.
Whether this system was mature or not was debatable, but the theoretical framework definitely existed.
Ou Zhanpeng's operational plan was, in essence, to convert Expedition One's altitude advantage into a speed advantage, thereby breaking through the interception and destroying the targets.