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Isn't maybe a case for dark matter? Maybe instead of looking for hypothetical planets, can we explain this with dark matter? Same as we did with the unexplaine
by ccozan 10y ago
Isn't maybe a case for dark matter? Maybe instead of looking for hypothetical planets, can we explain this with dark matter?
Same as we did with the unexplained galaxy rotation of outer regions.
- petewailes 10y agoShort answer - no. There is a long answer, but it requires enough knowledge of physics that you wouldn't have asked the question. But suffice to say, there's no chance whatsoever that this is dark matter.
- stuff4ben 10y agoWrong. Short answer - yes. There is a long answer but I too can be an Internet scientist and offer no explanations for my reasoning except "trust me, I know more than you do" as a certain political candidate is known to do (yes I went there). Also looking forward to an epic beatdown of mounds of scientific evidence that is way above my head. But at least I will have gotten you to say more than "trust me".
- petewailes 10y agoPithy answer - dark matter, whatever it might be (WIMPs or otherwise) is most importantly, Weakly Interacting (the WI in WIMP). It appears to clump around gravitational structures, acting like normal matter, but in more of a field way, rather than a matter way (think of it like a fluid filling a container, with uneven density - where the density is higher is where you've got matter pulling at it). For dark matter to be causing this, you'd need some exotic form of something that's already exotic - it'd have to be able to interact with an intensity we don't associate with it. It'd also be defying what we understand it to normally do (you'd need something to make it pull into a lump from how we think it behaves, which predisposes a physical structure like a planet). So, is there some massive errant lump of dark matter pulling the solar system around? From what we infer about how dark matter behaves from observation, no. (The fluid thing is not an entirely accurate model of how dark matter works, but it's a decent enough metaphor. However, this gets very complex and I'd rather not spend the rest of the day getting into ever more detail about theoretical physics.)
- reitanqild 10y ago@stuff4ben: mission accomplished I guess? : )
- stuff4ben 10y agoIndeed. Thank-you petewailes! And I think I actually understood some of that too.
- petewailes 10y agoMy pleasure :)
- nonbel 10y ago>"(you'd need something to make it pull into a lump from how we think it behaves, which predisposes a physical structure like a planet). So, is there some massive errant lump of dark matter pulling the solar system around? From what we infer about how dark matter behaves from observation, no." Apparently people find it plausible that dark matter consists of primordial black holes: "An intriguing alternative view is that dark matter is made of black holes formed during the first second of our universe's existence, known as primordial black holes. Now a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, suggests that this interpretation aligns with our knowledge of cosmic infrared and X-ray background glows and may explain the unexpectedly high masses of merging black holes detected last year." http://www.nasa.gov/feature/goddard/2016/nasa-scientist-suggests-possible-link-between-primordial-black-holes-and-dark-matter http://www.nasa.gov/feature/goddard/2016/nasa-scientist-sugg... So I don't see how the "clumped/lumped" dark matter explanation can be dismissed, black holes are basically lumps of pure mass right?
- Arnt 10y agoBlack holes are far from the earth, as proved by the continued existence of the earth.
- 10y ago
- ProAm 10y agoOr you could google dark matter and find out why, don't treat HN like reddit, the snark wasn't needed. It's pretty straight forward this why his answer was correct.
- SomeStupidPoint 10y agoI don't think it's obvious from a simple Google search why a material capable of explaining things about galactic orbits and large scale gravitational effects can't also explain localized orbital effects. There's no clear distinction in kind of effect, only scale. Perhaps instead of not contributing (by shouting RTFM when there isn't a manual for beginns on that topic), you could give a basic summary of why that's the case. If it's so simple, please outline in a line or two why dark matter can only impact large scale orbits (eg, galactic or bigger), and not cause localized or small scale effects (eg, solar system sized).
- crispyambulance 10y agoIt would be far simpler and more direct to FIRST rule out an undiscovered massive planet before seriously considering something as strange as gigantic chunk of invisible dark matter.