from the custom-luxury-planet-building dept.
AnonTechie notifies us that The Register is reporting on research from Harvard exploring comet dynamics.
Comets may not be the product of the Sun exerting its influence over rocks in the Oort Cloud, but may instead be pushed Earth-wards by dark matter. So say Lisa Randall and Matthew Reece from Harvard's Department of Physics, in a paper titled "Dark Matter as a Trigger for Periodic Comet Impacts". The pair write that "Large meteorite strikes on Earth cause big impact craters that are very likely responsible for some mass extinctions" and note that clusters of such collisions come along about every 35 million years. They therefore ponder where those space rocks come from. After dismissing the "Nemesis" theory (the Sun has a dark, invisible, companion) they wonder if the Solar System's path through the Galaxy sometimes intersects with denser-than-usual regions of space, which give Oort Cloud rocks a nudge towards the Sun.
(Score: 2, Funny) by Runaway1956 on Wednesday March 05 2014, @03:45PM
It's the Galactic Federation doing it! They use their dark matter beams to push those rocks at us! They won't permit us to return to space, even though it's been tens of thousands of years since we were exiled to earth!
(Score: 1) by Runaway1956 on Wednesday March 05 2014, @04:02PM
All the Way Back
by Michael Shaara
(Score: 0) by Anonymous Coward on Wednesday March 05 2014, @06:08PM
Enter Adagio For Strings: https://www.youtube.com/watch?v=CXNQNeLDg5s [youtube.com]
(Score: 1) by Runaway1956 on Wednesday March 05 2014, @06:40PM
I spent countless hours playing Homeworld, and then Homeworld 2. Those are the only games that I have ever paid full price for, because I wanted them - as opposed to the games my kids wanted.
(Score: 4, Funny) by VLM on Wednesday March 05 2014, @03:48PM
"intersects with denser-than-usual regions of space"
AKA the astrophysics version of the old "yo mamas so fat that ..." joke.
(Score: 4, Funny) by ngarrang on Wednesday March 05 2014, @04:46PM
In the clothing industry, they call that "relaxed fit", thankyouverymuch.
(Score: 2, Funny) by dublet on Wednesday March 05 2014, @05:13PM
Yo mama intersects with such a denser than usual region of space that Stephen Hawking published a paper called "Information Preservation and Weather Forecasting for Black Holes" denying her existence as was traditionally accepted.
Burn!
"If anyone needs me, I'm in the angry dome. [dublet.org]"
(Score: 5, Insightful) by Barrabas on Wednesday March 05 2014, @05:03PM
There's no clear consensus [wikipedia.org] that periodic extinctions exist. Some say it's 62 million years, some say 35 million years, and some say there's little or no correlation. And there's significant [statistically] confusing issues such as older fossils being less frequent, less productive fossil fields being less studied, and so on.
(Score: 3, Interesting) by Fluffeh on Wednesday March 05 2014, @09:38PM
Just because there is a large impact doesn't mean that EVERY large impact will cause mass extinctions. There are loads of craters all over the earth that we can study and through geology, weathering and the like determine how long they have been around - and they are just the ones that hit land.
Also, consider that no-where in the paper does it state that these events are running like clockwork, as our system orbits around the galaxy center, it takes 240 million years for one orbit. Even if the "dense patches" don't move/change on their own, it is still going to be a 240 million year cycle - and not even that ensures that travelling through a dense patch will result in a large impact - it just means that the Oort Cloud gets extra forces being applied to it, sort of like knocking a chessboard - maybe a piece falls off, maybe they just shift a place.
(Score: 5, Funny) by infodragon on Wednesday March 05 2014, @05:15PM
We're in the dark on how the dinos died (Volcano, Asteroid, ...) Now that statement may be more true than what we ever believed!
Don't settle for shampoo, demand real poo!
(Score: 3, Informative) by Yog-Yogguth on Wednesday March 05 2014, @06:23PM
No they didn't [xkcd.com] they only evolved :3
Bite harder Ouroboros, bite! tails.boum.org/ linux USB CD secure desktop IRC *crypt tor (not endorsements (XKeyScore))
(Score: 2) by FatPhil on Thursday March 06 2014, @12:10AM
It's not the sun's gravity doing it. It's not global warming doing it. So it must be dark matter doing it.
Alternatively, the "scientists" could propose testable and falsifiable hypotheses, and I'll retract my claim.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves