How to model Eccentricity, Obliquity and Recession in Excel

[DnA 9413]

Hi Everyone,

I'm writing a sci-fi book that looks at humanity's response to the end of life on Earth and their voyage to a new home. The first part of the book is how a large mass of dark matter in the relative vicinity of Earth (50 light years?) starts the process of extending the eccentricity of every object in our solar system as well as neighboring systems. This eccentricity will drive massive climate changes that end the possibility of life on Earth and forces humanity to seek a new home beyond our local star systems. For the book, I'm giving Earth ~2000 years until there is no possibility of living on the surface anymore.

From the point where humanity first discovers the inevitable end of the Earth to the end of the first part of the book when humanity is able to travel long distances, the book will focus on different points in time and explore what is happening culturally, scientifically, politically and religiously.

For each chapter, I want to put the new coordinates of the Earth (and maybe the moon) to help the reader understand the extent of the change.

Does anyone know how to create a formula(s) that would assume a large enough mass to pull the Earth out of it's orbit and give me new eccentricity, obliquity and recession numbers based on any year I input? I assume we would also need to determine the rate of eccentricity.

I am not a scientist or mathematician, nor do I play one on TV. Any help folks can offer on this mathematics/physics is appreciated.

Thanks,

Dan

 

[stefan r]

The gravity pulls on Jupiter and the Sun too.

You can throw off Earth's orbit by sending a rogue planet between the Earth and the Sun. As the object passes the forces are opposite.

I think you are looking for the inclination not the obliquity.

 

[DnA 9413]

Hi Stefan,

Thanks for the idea about the rogue planet. I did think about that, but I assume astronomers would see this planet long before it got close enough to affect Earth. Plus, it would then need to become part of the story, where the dark matter once identified, does not become a part of the story.

Also, I want a mass so big that it affects surrounding systems so that whatever plan humanity comes up with to find a new habitable home, they can't reasonably try using less than light speed designs to get there. And I want to have an exploration section of the book and LTLS engines can't support that.

I got obliquity from reading about the Milankovitch Cycle. You're right, I am looking for inclination from the plane of the ecliptic.

Thanks again,

Dan