Analysis / Stellvia of the Universe

The mathematics of the Great Mission
Assuming that "Hydrus Beta" is Beta Hydri, it was 24.33 light years away from Earth before it went supernova. Assuming that the first shockwave was pure energy that moved at the speed of light in vacuum (and disregarding the improbability of it not dispersing per inverse-square law), the star exploded in 2142. The physical debris from the explosion hit Earth in 2356, traveling through space for around 213 years, at an average speed of around 34 thousand kilometers per second or 0.11 of the speed of light. At this speed, it takes about 35 hours to traverse the Solar system.
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