I used to think this idea was kinda silly and based on flimsy and handwavey justification, but then I saw a colloquium by a famous black hole physicist on it. Now I REALLY think this idea is silly and made up!
Oh! They don’t mean that black holes must come in perfect pairs! The headline makes it sound like it’s about wormholes across vast distances. No! What they’ve found is a stable “orbit” solution for the two-body problem. Normally when you place two bodies anywhere in an empty universe, they will gravitate towards each other until they collide. But in a universe with dark energy, there is some perfect distance between them, where the accelerating expansion perfectly counterbalances the accelerating attraction. They’ve used general relativity math to actually calculate such an arrangement.
The “stable” orbit in this case is the same kind of stable as a pencil balanced on its sharp tip - if it tilts even slightly one way it will fall out of control. Although they tantalize the idea that they might be able to make it truly stable against small perturbations once they finish their spinning black hole solution.
I would like to have known some specific numbers examples! Like if you have as much dark energy as our universe, and two 10-solar-masses stellar black holes, how far apart would that be? Is it like 1Ly or 1MLy? How far for two 10-million-solar masses supermassive black holes? The formulas they created should give the exact answer but I am not skilled enough to substitute the correct numbers for the letters.
In the best case, the detection is at the 2.4 sigma confidence level (less than the usual 3 for reasonable confidence and will below the 5 required for strong confidence), and if previously suspected issues with the instrument are true, the detection could disappear completely.
I do not have a strong confidence in this result. (But at least they didn’t publish it in Nature, in which case you would absolutely know it’s wrong…)
Seems like you’re on the west coast (USA). Me too.
I’m hoping I get to duck out for a bit and take it all in after bedtime and chores. I won’t be able to pull out a telescope tonight, but sometimes binoculars surprise me.
You probably won’t see much in terms of globular clusters in binos. I feel like you should be able to resolve the Leo triplet in them, though I expect it would be a challenge. Probably your best bet is the beehive cluster in Cancer, which should be near the Zenith, the little beehive cluster in Canis Major, and some of the easier double stars (the second star out from the cup on the handle of the big dipper- mizar and alcor- is great) and the Orion belt stars. Good luck!
Wow, I never see NGC 4945 pop up in the news, science or otherwise. I looked at it as part of my undergraduate thesis 20 years ago, so I’m always keeping an eye out for it, and almost every time I get a ping it turns out to be M88 or the Sculptor galaxy.
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I flat out don’t accept the notion that some starts have no planets. As far as I am concerned, if we have 8 major plantes and on average, 40% of planets are ejected, we should assume the average number of starting planets is 11.
This is like saying, “If a carbon atom has 12 electrons, and on average it forms 4 covalent bonds, we should assume all atoms start with 16 electrons.”
Update: moved to Monday (tonight) because transparency sucked and I was tired.
Seeing: very little or slow twinkling
Transparency / Light pollution: Polaris visible, only one of the cup stars of Ursa minor visible to the naked eye. This is actually slightly better than normal for my area.
Equipment: 12" dob, 1520 mm focal length, 2" 2x Barlow, 2" 34 mm wide field eyepiece.
What I hit: M44: sketched it from my 10x50 RACI. I love finding M44 because cancer is dim as fuck, and I’ve got a cool trick where I just make a right angle with my left hand, pointer finger touching Pollux, thumb touching Procyon, M44 will be right in the 90 degree angle.
M65, M66 again. M66 was actually readily apparent to me, for some reason, where M65 took a bit of work to resolve. Did not manage to resolve NGC 3628. I also accidentally resolved another galaxy about three degrees south of and about two degrees below Iota Leonis. Found it purely by accident, couldn’t find it again, looked very slender, stretched almost across the view in 100x (34 mm wide field + 2x Barlow).
What I attempted: Bode’s galaxy. Spent probably an hour trying to starhop to it with different tricks (I think the thing that got me closest was drawing a line through UmA’s front elbows and shoulders and following that down to the level of Alioth. That got me onto a very neat little square of stars with a trail pointing towards the horizon, which I followed again and again to nothing. Very frustrating. I tried again to hit the owl nebula and cigar Galaxy, also no dice. Not sure if I just suck this bad at star-hopping or if the light pollution is really kicking my butt.
I spent so long on it that I ran out my clock and had to choose one last thing to do. Bootes was now plainly visible in the mid-altitude east, so I decided to try and hit M3 by making a right triangle with epsilon bootes as one angle, Arcturus as the right angle, and M3 as the last angle. Didn’t work. Tried a few other spaghetti plate strategies to find M3 and got nowhere. I mostly tried slowly slewing over at 100x mag, which I know is low for globs, but I figured it would at least stand out as a kind of weird bullshitty star that I could investigate, but nothing stood out.
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