Facepalm moment – sometimes scientists use $10 words and the message just gets warped. Headline writers will just destroy the meaning of a story. Subtlety is NOT the media’s strong point.
A thin disk of dark matter running through the Galaxy might be behind the large meteorite strikes that are thought to be responsible for some of Earth’s mass extinctions, including that of the dinosaurs, two theoretical physicists have proposed.
The model is based on a hypothetical form of dark matter described by the authors and their collaborators last year as a means to solve a separate cosmic conundrum. The existence of such a ‘dark disk’ could be tested soon by astronomical observations.
Mario Livio, an astrophysicist at the Space Telescope Science Institute in Baltimore, Maryland, who was not involved in the research, says that the latest idea, which brings together two speculative and very different theories, is “very interesting”, even if the evidence supporting it is far from compelling.
There are a few VERY IMPORTANT details to notice in that quote: “have proposed”, “hypothetical form of dark matter”, “evidence supporting it is far from compelling”. Neat and far-out hypotheses are fun but maybe they should be kept at a strictly speculative level until they are more concrete. From experience, I know that enthusiastic readers only see some keywords like “dinosaurs,” “meteorites” and “dark matter” and jump to conclusions that this is a new and valid idea. The headline here doesn’t help, it creates misinformation.
The authors suggest that as the Sun oscillates up and down, it crosses a denser layer of dark matter — like the ham in the middle — causing a gravitational push and pull that disturbs comets in the Oort cloud.
Previous models could not account for a gravitational force strong enough to cause the effect. But Randall and Reece show that a thin disk of dark matter at the centre of the Galaxy could do exactly that, causing comet storms with a periodicity of about 35 million years.
See, that’s not absurd and it can be tested. But I am concerned that it was put out there TOO soon. And since it included the sexy words “dark matter“, it makes for a juicy story.
Despite its speculative basis, Randall says that the exercise is valuable. “This is trying to turn this somewhat crazy idea into science, by saying we will make predictions based on it,” she says. “We’re not saying we think it’s 100% going to be true.”
Oh, too late. The Daily Mail has it…
Were dinosaurs wiped out by DARK MATTER? Force sends comets hurtling towards Earth every 35 million years, claims theory
As solar system orbits centre of galaxy, it moves around in 70m year cycle
Means it would move through a dark matter disc every 35 million years
This corresponds to increase in pattern of comet impacts on Earth
Researchers conclude this could have led to impact that has been linked to the extinction of the dinosaurs 66 million years ago
And IBT/Yahoo news has this headline (which is probably as far as people are going to read): Were Dinosaurs Killed by Disc of Dark Matter?
NO, DINOSAURS WERE NOT WIPED OUT BY DARK MATTER. This is a proposed idea, it has not been shown to be true in any sense.
Sometimes, I really think scientists have to learn and REMEMBER how media works. They HATE qualifiers and only key on the dramatic words you use. So, we have this muddled mess. Good going.