"The surface of the object is very 'smooth' and the number of impact craters is small, which indicates that its geological structure is relatively active, and the data sent back suggests that Europa has an internal layered structure and may have a small metal core.

Last month, one of the swarm scout bots we sent managed to break through Europa's defenses and land on the stars, sending back important information.

On Europa's surface, we find clayey minerals, which means that Europa's surface may have formed soil, which has been modified by aliens. ”

The report of the staff committee made the faces of each general sink.

A planet that has been transformed by aliens will not be able to match its defensive capabilities in the Battle of Europa.

All the generals here participated in the war of that year, and at that time, the Martians organized a powerful army, but in the end, they were constantly frustrated, and even after the landing operation, they almost couldn't get out of the way, and finally had to destroy the entire planet.

Seeing that everyone's eyes fell on him, Zhang Binhui stood up: "This war is going to be very difficult, we all know it.

The reason why Europa fought hard was because we didn't have the experience of fighting aliens in outer space, but now it's different.

Our equipment is more advanced, our weapons are more reasonable, our tactics are more mature.

Before I arrived, the senior generals of the Alliance Academy carefully analyzed Europa's situation with me, and they gave very good advice. ”

Speaking of which, Zhang Binhui clicked on Europa's detailed planet.

"You see, Europa's environment is very characteristic, first of all, its atmosphere. Europa's atmosphere is excellent, and its surface is covered with an extremely thin atmosphere composed mainly of oxygen.

Of all the moons of the solar system known, only seven have atmospheres (the other six are Io, Callisto, Titan, Ganymede, Titan, and Triton).

Unlike Earth, the oxygen in Europa's atmosphere is of abiotic origin. It is likely that the impact of charged particles and the exposure of ultraviolet rays from sunlight cause some of the water molecules in the ice on Europa's surface to decompose into oxygen and hydrogen, which escapes due to its low atomic weight, while oxygen with relatively high atomic weight is retained.

Because of this feature, the alliance believes that the alien will be arranged here, because of the abundance of oxygen, the alien has the advantage of the atmosphere.

Because Europa is slightly smaller than the Moon, its atmosphere is very thin, and strong tropospheres like Earth and Europa don't exist, so our first battle will be fought in Europa's space and atmosphere region.

In light of this situation, the Alliance has supported us with a large number of crystal cannons, weapons for space combat. We have to be prepared for this first battle.

First, we need to prevent the aliens from coming from Jupiter, and the long-range firepower of Battlestar must completely cut off this path.

The average distance between Europa and Jupiter is 670,900 kilometers, and it takes only three and a half days to complete one revolution. Its orbit is very close to a perfect circle, with an eccentricity of only 0. 009。

Like other Galilean moons, Europa is tidally locked, so there is a hemisphere that is forever facing Jupiter.

Second, we need to cut off the Xenomorphs from Europa's reinforcements, which are the last three known Xenomorphs in the solar system.

So the point of the first battle is to punch this awl and isolate Europa completely. ”

The generals of the Great Western Kingdom nodded, this kind of combat method has already happened on Europa, everyone has experience, and the alliance is at peace with them.

Zhang Binhui nodded a little, doubled the holographic map in the combat research room, and the entire geographical environment of Europa was presented in front of everyone.

"Look, this is the record of Europa by the Alliance's expeditions hundreds of thousands of years ago, Europa is a planet abandoned by the Alliance, but its environment still has superiority and peculiarity.

Europa's environment is very suitable for life, and it was once the second most habitable planet in the solar system after Earth. By the way, your Mars doesn't count, it's the result of your transformation. ”

Hearing Zhang Binhui's addition, the generals of the Great Western Kingdom let out a proud laugh, which was their pride.

"Europa has ice, water, and rocks, and its surface is basically covered by a hundred kilometers of ice, and below it are oceanic and silicate rocky stars.

But there is one thing that the Scout robots don't notice, and along these areas, Europa's beagulated ocean surface reveals its 'surface'. ”

All the generals sighed, and what they had learned was the same as that of the earthlings: Europa was completely covered in thick ice, and they didn't expect the Alliance's data to say that part of the ocean was exposed to the "ground".

Zhang's finger pointed to the dark stripes that spread all over Europa, which the Martians had also noticed, but they ignored them.

"The most striking feature of Europa's surface is the dark stripes that spread across the planet.

According to data from previous Alliance expeditions, the streaks were formed as a result of the plates on both sides of the streaks moving in opposite directions, and the ice covering Europa burst open. ”

Zhang Binhui pointed to these stripes and explained: "Here, the larger stripes can span more than 20 kilometers laterally, and we can observe that the dark part of these wide stripes has a blurred transition with the outer edge of the plate.

Europa's regular veining, with its wide stripes sandwiched with light-colored fine lines, is due to the cracking of its surface crust and the exposure of warmer underlying material. This is the ocean that emerges from the ice.

The expedition had calculations and concluded that these ice bursts were caused by Jupiter's gravity.

Jupiter creates extremely powerful tidal pressures on Europa, which have a much greater impact on Earth than the Moon.

Since Europa is tidally locked, it always maintains one direction towards Jupiter. Fixed pressure patterns create specific predictable fracture patterns, and thus these regular streaks are formed on Europa's surface.

This is where we should pay attention in the third game:

Europa's surface crust rotates faster than its interior, and Europa's outer surface is like a layer of ice crust that does not rotate at the same speed as the sea below, it is like a moving wall that our troops must be prepared against at all times.

Because of this, the high-speed rotation of the ice, combined with Jupiter's strong gravitational pull, creates monstrous tides in the cracks, and those exposed 'surface' oceans will regularly pass through large waves up to 100 kilometers high, and to enter Europa's interior, we must also pay attention to the prevention of large waves. ”