The Beginning
Once, in Serpulos solar system, a lush planet filled with large oceans existed. Its inhabitants called their planet "Asthosus." It contained abundant life.
A civilization of great power and knowledge inhabited Asthosus. These people were native to the planet and did not colonize it by landing on Asthosus from a different planet. Their life as they knew it was created on Asthosus itself.
Despite their great power and knowledge, the people of Asthosus were not as advanced scientifically as other planets in the solar system. They had only just invented interplanetary travel.
Struggle For Power
Asthosus had very few worries. War and diseases were but few. The only thing that put a strain on the Asthosians was the heat of the sun, as Asthosus was comparatively close to it.
The only other issue the planet constantly faced was a fight for power between two political parties.
The one party - called the Trumir - thought that the technological advances brought only good things. Trumir tried to advance the research in all fields further.
The other party - called the Arumis - thought that life on Asthosus was better before inventing interplanetary travel and that Asthosus should return to that state.
The Beginning of the End
A few years after the invention of interplanetary travel, the Asthosians began experiments on terraforming.
Their first test ran on Trecara, Asthosus' moon, which had been a lifeless celestial body without an atmosphere.
The terraforming test was successful, and Trecara was transformed into a lush and life-friendly moon.
An outpost was created on Trecara to help monitor the solar system and the state of Asthosus and its people.
After a few years of this outpost existing, a powerful force generator was installed in it to deflect a major amount of the sun's heat and radiation.
Furthermore, two devices were installed on Asthosus and Trecara to connect and protect both from threats other than the sun's heat.
Because of the great success of terraforming Trecara, one of Asthosus' oceans was tried to be terraformed into liveable terrain for the thriving expansion of the planet's people.
While this experiment was in progress, a solar wind discharge erupted from the sun.
Luckily, the force generator installed on Trecara was able to deflect most of this discharge and prevent further damage. Or so the Asthosians thought...
The Disaster Takes Its Course
A large part of the eruption energy managed to bypass the force shield and directly hit the terraforming devices that were running.
The machines went out of control and threatened to destroy a major part of the Asthosian civilization.
Luckily, though, the best scientists were able to avoid this catastrophe by launching the terraforming devices into outer space last-minute where they exploded.
Because of this mishap, the Arumis party managed to finally gain control and take power over Asthosus.
A few hundred years went by. Asthosus and Trecara were still thriving.
Because of the Arumis gaining power, the outpost on Trecara was abandoned, and the force projector that had been protecting Asthosus against the sun's threats was out of power and no longer functional.
The Arumis made sure to create weapons capable of mass destruction.
The End is Near
One day, as a result of another planet's experiments, a devastating geomagnetic storm was released from the sun.
The storm hit Trecara first, disabling the final pieces of infrastructure that were still running to protect Asthosus.
Scientists rushed to reinstate the devices.
While working on this device, it ruptured in a disastrous explosion that took down multiple major cities nearby and also hit the storage facility for the most powerful Asthosian mass-destruction weapons.
Millions of civilians died in great agony.
Because of these catastrophes, Asthosus' atmosphere was almost completely destroyed.
Temperatures rose slowly but constantly.
At some point, all attempts at saving Asthosus were in vain.
The entire population was wiped out by the extreme heat.
The Aftermath
The heat became so great that even Asthosus' oceans started to dry out.
All life was destroyed at this point.
Only a tiny bit of life managed to survive in small puddles of oasis water.
Thus, Asthosus turned into the rough and harsh planet we know it as.