Jordan resumed, "OK, now about the catastrophe. If you search your mind on the subject of astronomy you will come to the information about a star some call Nemesis. Some think it is our sun's binary twin but it is not.
Our star has no companion because the other stars in the nebular nursery pulled them too far apart to remain in gravitational contact with each other; they are three of the rare single stars, our sun was one of triplets.
By the way one of those stars is the home star of the Kindred, the newest peoples in the Federation. You will find remarkable similarities between them and us; we likely share the same seeds of life.
Our sun travels around the galaxy at a slower speed than most and we spend a lot of time out of our arm of the galaxy. The reason we do is because our star does not travel a horizontal path but moves like a swimmer doing the butterfly stroke or a dolphin at play. During our orbit around the galaxy we spend most the time somewhat above or below the galactic plane and behind our galactic spiral arm.
Every five hundred million years or so the front of our galactic arm catches up to us. If we are above or below the galactic plane little harm is done, if we are in line with the plane nothing will happen most of the time because space is mostly, uhm, space. Sorry."
The peer gave him a disapproving glare then smiled and praised his command of language.
"Thank you. Be that as it may there are times that catastrophes do happen. That has happened four times since the birth of life on Earth. There have been major extinctions on those occasions. Even rarer is what is about to happen.
Our suns real Nemesis is ahead of us, it is moving even more slowly than we are for the same reasons we are but was not born until our sun was a billion years old. It is a smaller somewhat orange star that has four planets orbiting it now.
Its vertical span is greater than ours, which puts their forward motion slower than ours. The odds of the two being in the same place at the same time are, if you will pardon the expression, astronomical."
He received the groans and giggles of admiration he was seeking from some of the peers with that line and the frown from Mom he had expected.
"Oh, two for two. Excellent," Jordan said.
The peer now understood why several Monty Python skits were in their memory. All suddenly had Eric Idle's song about the Universe running through their minds.
Dad seemed to know that and paused long enough for all to get it out of their heads then continued.
"We are going to catch that star in six years. The first time it happened the two planetary systems almost wiped each other out, the systems clobbered each other. Uranus had to reform, one of their planets crashed into Earth and the debris formed our moon. Venus was hit so hard that its rotation was nearly toppled over.
Our sun took two planets from the other system, Triton and Titan, and they took one of ours. That planet has life on it and as of now has no name. One of you will discover it but will not announce the discovery for reasons you will learn later.
That crash was over three billion years ago.
There is no chance the planetary systems will interact directly this time.
Planets will not collide.We have gone past each other peacefully every time since then.
?But that will not be the case on this occasion.The inner and outer Oort Clouds of both systems will be subjected to strong gravitational waves meaning both systems will be bombarded with comets and asteroids.
The planet with life orbiting the other star will suffer a forty percent extinction rate but the higher plant-like forms will survive. There are no higher animal forms on the planet yet.?
Their Protectors will only monitor it.
We are moving towards each other at a high speed, we are going down as they are moving up. Their vertical speed is faster than ours so their outer limits will push our outer limits hard.
The gravitational waves will affect many comets and asteroids in the two belts and their orbits will be disrupted. Some of those changes in the orbits of asteroids, comets, and planetoids will put them in the path of the planetary orbits.
Many are bigger than the ones that ended the dinosaur age.
At least three of those will impact Earth.
?As you would expect the sun, Jupiter and Saturn will absorb most of the heavy blows. However some like the planetoid Charon will be hurled into the inner solar system and will likely brush or maybe impact Venus.
Several large ice balls will head our way and Pluto's satellite Hydra is likely to hit our moon and Pluto itself will spiral into Mars.
It is possible that the other star will recapture Triton.
Titan may join Jupiter's moons and replace Io, which will be hurled into Jupiter.
It appears less possible but well above a zero chance both Saturn and Uranus will merge with Jupiter.
It is also possible that the other star will also capture Neptune.
All of those scenarios will take hundreds or thousands of years to play out, if at all. There are many other non-zero possibilities for both systems."
Dad paused the narrative to allow the animation to catch up. The peer had some inner resistance to seeing it as future events but soon all did.
"We do not know how the bombardment will affect the life on Europa and Ganymede but extinctions are likely. Jupiter's mass will increase substantially and boost its levels of heat radiation but not enough to begin fusion. Still its habitable moons will benefit from that.The Earth will be on the far side of the sun and Jupiter for the biggest bombardment but the barrages will come from a bit below the galactic plane, we will get hit hard.
Most of that will come a bit over a year after the first and smaller barrage. That first barrage will come in just over two years from now. Gravitational disruptions have already started. Soon some astronomers will be wondering what Pluto is doing starting with our own astronomer."
.Jordan nodded at Marc when he said that then nodded at Hu before saying; "Marc and Hu will find the star within three months and will announce their findings in just six months.
The world leaders will understand the peril a few months after that. They will have two years to build shelters but many will delay any action for more than a year.?By then they will know about us."
"That will allow many people to survive. Why do we need a shelter?" Mauro asked.
"Good question, Jordan answered. "The first bombardment will kill about a billion people, an enormous number but will still leave billions alive if not well. It will be around the Gulf of Mexico just like in the last great extinction.
After weeks of smaller but damaging impacts that will spawn some tremendous storms a somewhat large asteroid will plunge into deep water near the coast of Texas nine months before the barrage of year two. That shock wave will flatten everything from Mexico to Florida to Cuba. The resulting ocean wave will climb over a hundred meters on all shores around it. The wave will reach Dallas, Shreveport, Jackson, and Birmingham. All of Florida and all of the Yucatan peninsula will be overrun. All shorelines of the Caribbean Islands will be scoured.
Every coastal city from Houston to New Orleans, Cancun, Miami and Havana will vanish. Tsunamis of more than ten meters will occur around the world. The Earths weather will become even more chaotic."The animation on the screen was matching his description, which made the peer uneasy.