4

Let's look at historical data. SN 1054 has an estimate of its distance from Earth at 6500 ± 1600 light years. It was visible by day. Then there is SN 1006, which was bright enough to cast shadows! It happened about 7,200 light years away from us. Astronomers from the time estimated its brightness to be ¼ that of a full Moon: Egyptian astrologer and ...


2

The key is in your point #8: After all, Why would a ship give up its speed? You give up speed because you need to. You don't go fast for the sake of going fast, you go fast with the intention of going somewhere. If you're going 1000 km/s, you can't dock with a space station, or enter orbit around a planet, or do many of the other things you'd want to do ...


1

Since you're not worried about life, and they can manipulate time (as mentioned above), that's all you need to do. Simply accelerate or decelerate the relative passage of time on Earth. If they arrived, say, 200 million years ago and slowed down Earth's relative time so that, basically, Earth "now" would look like it did, say 100 million years ago, ...


1

Your aliens could possibly make this work by increasing the acidity/salinity of ocean water to increase erosion on the continents. This would cause the total landmass to shift, over time, into the sea. Once there would be enough soil deposits from the erosion, new continents would be formed by the buildup of said deposits. To make this even more drastic, ...


1

Many of the issues you described stem from forgetting one key fact: Velocity is not an absolute. It is relative. Ships flying at 1000 km/s are not inherently immune to projectiles flying 1 km/s if those proectiles are fired by another ship going 1000 km/s in the same direction, because the projectiles' 1 km/s is added to the firing ship's 1000 km/s. If it ...


1

The Doctor Who episode The day of the Doctor features the extremely powerful weapon The Moment. This weapon could destroy whole galaxies in matter of seconds and therefore had a sentient operating system to make sure that people/creatures who intended to use it were absolutely sure about this.


1

A Gun without an AI is a War Crime Expanding international law and reliance on public opinion make going to war much more complicated than it used to be. You practically need a law degree to tell you who, when, where, how, and why it is acceptable to kill someone, not to mention superhuman reflexes to make sure what you perceive is a real threat. All the ...


1

Independent Mission Say you are a super-being that wishes to keep the universal population "under control". You might craft a few thousand man-portable planet killers that you seed across the countless galaxies. Your goal, however, is population reduction. Not eradication of life. So, each man-portable planet killer has an artificial intelligence ...


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