Slashdot Mirror
Hubble Builds 3D Dark Matter Map
astroengine writes "Dark matter can't be spotted directly because it doesn't interact with electromagnetic radiation (i.e. it doesn't emit any radiation and reflects no light). However, its gravitational influence on space-time can bend light from its otherwise straight path (a phenomenon known as 'lensing'). Using a sophisticated algorithm to scan a comprehensive Hubble Space Telescope survey of the cosmos, astronomers have plotted a map of 'weak lensing' events. Combining this with red shift measurements from ground-based observatories, they've produced a strikingly colorful 3D map of the structure of dark matter."
...especially when you consider it's a picture of something that very possibly doesn't even exist.
There isn't any "scale bar" because you are not looking at something at any fixed distance! You are looking at (theoretically) blobs of stuff at various distances.
It's not arrogance; frankly, a true scientist is thrilled at the prospect of being proved wrong. It means they're answering some long-standing questions and posing countless new ones. Furthermore, the concepts of "dark matter" and "dark energy" are still only theories; scientists have yet to definitively prove the existence of these entities. These theories just happen to be the best explanations for what scientists observe.
The bottom line remains what osgeek above me said: it's easy for you to call the scientists who postulate dark matter "arrogant" considering it's something that has about as much impact on our daily lives as Einstein's Theory of Relativity does (which, when it was being proved, required very specific measurements to be taken, measurements that could only be gathered in a solar eclipse...how's that for completely unnecessary to quotidian life?).
No, right now we can't definitively prove that the 3D image referenced in TFA is indeed dark matter. But within the parameters of the current hypothesized model, that is what scientists believe to be pockets of dark matter.
"I'd just like to emphasise that taking a million years isn't a metaphor here..." -Rich Bradshaw