Dinosaurs Done In By... Dark Matter? 135
bmahersciwriter writes "Theoretical physicists propose that the Sun periodically crosses into a dense layer of dark matter sandwiching the Milky Way. The gravitational push and pull that this creates disturbs debris in the Oort cloud sending deadly comets and asteroids ricocheting around the solar system. This passage happens, their admittedly speculative model suggests, every 35 million years, which jibes somewhat with evidence on impact craters. Take it with a dino-sized grain of salt."
Re:Statistical analysis of craters (Score:4, Informative)
Of course, if their hypothesis is correct all the statistical data will have to be re-calibrated to account for the occasional rain of meteors.
Also note: Age estimates for larger impacts will have smaller error bars.
Re:This seems to make a lot of assumptions (Score:5, Informative)
Re:magic (Score:5, Informative)
Dark matter is not THEORETICAL. There is direct evidence for it. Quoting from the relevant wiki:
In other words, gravitational lensing of light waves - which is 100% direct evidence of matter - shows a region where there is matter that is clearly non-baryonic (i.e. does not interact with the electromagnetic field, a.k.a. "dark"). This is not subject to dispute. The question of what, exactly, is dark matter - is indeed still a subject of scientific research. There are, however, a number of super-symmetric theories which posit super-partners for well known particles, the most stable of which turn out to have the exact characteristics we're noting observationally. It is important to note that these theories were not tailored to account for the dark matter, but seem to fit the observational evidence quite well so far. As with all science however, theories are subject to falsification at any times as soon as new evidence comes on the scene.