Sci-Fi Story: Alien attempted to destroy life on Earth by setting an asteroid on course to collision

Question

I've only remember reading a very small section of it, mainly it was referred to in a discussion about "The Dark Forest" Theory on Reddit, however for the life of me I can't find the post again. The person posting the section argued that its not irrational for an alien civilisation to seek to destroy other potential rivals from forming by kinetically bombarding the rival's home planet using an asteroid during its infancy. This is because, to the dominant alien, there is a limited supply of resources in the universe and to let other species develop into space-faring species which can challenge them directly for it is insensible.

The premise of the story is that the impact event that caused the extinction of the dinosaurs 65 million years ago was actually caused by them, they launched the asteroid at Earth hundreds of millions, perhaps even billions of years, before any advanced life form existed. The goal is for the asteroid to hit the Earth when an intelligent life just start to develop technology, but early enough so that no defence can stop the asteroid, hence stopping a potential rival from ever making to the space faring stage. However despite the perfect hit using classical physics, even when the journey was hundreds of millions of years, their prediction were off as life on Earth developed more slowly than they estimated, ironically it was precisely that event that gave chance to our evolution.

This is more or less something discovered from a dialogue between two scientists from the story, I'm not sure if they found what technology is left of the now extinct alien race and discovered that fact by accident through examination of some remnant database on an exploration voyage, or they were at war with the alien race and found out through hacking and/or interrogation.

Again I'm not sure if this is a short story or a novel, I can't remember well enough as this was something I stumbled across and didn't think to save. I'm sorry if I don't have a lot of relevant information, just merely a short description, however this is all I can remember given my terrible memory.

Answer 1

A Time odyssey by Arthur C Clarke and Stephen Baxter

In the Time Odyssey series, not-so-benevolent godlike aliens start an endless mission to regulate the development of sentient life throughout the known universe, in order to prevent all other species from harnessing too much of its energy, which would only accelerate the inevitable entropic death of the known universe. Consequently, these "Firstborn" are destroying other intelligent species. 

The part where you mentioned destruction of Earth's life 65 million years ago by an asteroid is from Time odyssey. However this is done by the alien beings due to their obsession with "conserving the entropy of the universe" as they believed that any civilization that grows out of their home planet begins to rapidly utilize the resources and keeps on expanding.

Answer 2

The Dark Forest by Liu Cixin

The Battle of Darkness sets up the novel for the explanation of the central metaphor of the story. Back on Earth, Luo Ji and Da Shi discover that star 187J3X1 has been destroyed. This confirms Luo Ji's suspicions, and he explains to Da Shi the implications of the star's destruction. The universe is full of life. Life in the universe functions on two axioms: 1. Life's goal is to survive and 2. That matter (resources) are finite. Like hunters in a dark forest, life can never be sure of alien life's true intentions. The extreme distances between stars creates an insurmountable 'Chain of Suspicion' where the two civilizations cannot communicate fast enough to relieve mistrust, making conflict inevitable. Therefore, it is in every civilization's best interests to preemptively strike any developing civilization before it can become a threat.

The conversation between two scientists happens early in the book regarding the "dark forest" mentioned above. But the destruction by asteroid does not happen. Rather, an alien civilisation discovers the human broadcasts and tries to colonise the earth.

Answer 3

That sounds like "T" by Brian Aldiss, a title that is hard to search for. If I'm right, this question has already been asked and answered here -- check that answer to see if it sounds right, and if so we can mark this as a duplicate.