Airbrush

I always scan Astronomy magazine when I shop for groceries. If it has a story that keeps me reading for more than 10 minutes, I have to buy it. I don't have a college science education, I just love to watch programs about cosmology on TV.

That's a great answer to a simple but difficult question. 33%C is an incredible speed. They think the 2 outbursts are caused by the smaller one punching thru the accretion disk of the larger one, swinging around the larger one and punching back thru the accretion disk to be flung way out to far side of the ellipse. I wonder how long the interval between the 2 outbursts is? It must be a very tiny fraction of a second if it is moving at 33%C. http://www.caha.es/18-billions-of-suns-support-einstein.html

"OJ-287 over 3 Billion LY away, 18 Billion solar masses has a 100 Million solar mass SBH in a 12-year orbit around it. They estimated the outer edge of the accretion disk of the bigger one as only about 10 light weeks in diameter. "Ten light weeks is about 0.19 light years, or over 1.1 Trillion miles if my math is correct (60 x 60 x 24 x 70days x 186,000mi/sec = 1.116 Trillion miles) or 10,750 AU, or extending to about the middle of the inner oort cloud. The event horizon radius of an 18-Billion-solar black hole is about 54 Million kilometers or 33.5 Million miles, about a third the distance from the earth to the sun, inside the orbit of Mercury." ~from a few months back How fast does the smaller one whiz past the larger on closest approach?

Wikipedia on OJ287: They think the two super-supermassive black holes will merge in about 10,000 years. They think the 11 or 12-year periodic outbursts are caused by the smaller one crashing thru the larger one's accretion disk. "The maximum brightness is obtained when the minor component moves through the accretion disk of the [more] massive component at perinigricon." and the feeding frenzy begins and ends. http://en.wikipedia.org/wiki/OJ287

"...they seem to have caught a pair of black holes which are spiraling down into each other, on the way to merger, and radiating off the excess energy (which they have to do in order to spiral in closer) by having their orbit generate undulations in the geometry around them---gravity waves carrying off the excess energy." Have they calculated how long until the merger? Why do they have to radiate off excess energy as they spiral together? Will they accelerate in speed as their orbit gets closer and tighter (like the ice skater with arm out spinning faster as they bring their arms inward)? Are those 12-year periodic outbursts the result of each black hole crashing through the others' accretion disks? Imagine that, the most massive object ever detected. And as a bonus, it has a massive parter.

That's the kind of stuff I like to hear about! Thanks Martin.

Where did you read "receding at 6C"? The furthest quasars were much closer to us than 14.5 (you mean Billion) LY away when their light left them. Objects near the edge of our current visual horizon are not receding that fast. Now the furthest visible quasars and galaxies are about 30 Billion LY away, and they were between 12 and 13 Billion LY away when the light we now see started traveling towards us. The cosmic microwave background is now about 50% further, or about 45 Billion LY away. Maybe someone can resolve this better than I can.

You are right. Either the universe is infinite, or it is finite, but surrounded by infinity. Beyond the border of this bubble is the unknowable.

I like the theory the universe was created by a collision of higher dimensions. Like two bed sheets hanging parallel and very close together on clothes lines. When a wind blows the sheets will come into contact with each other (big bang) not at one point (not at a singularity), but at various regions of indefinite sizes. Our universe is the result of a collision of our local region on one bed sheet.

This is the first I heard of the "eddy effect" of a black hole. Would you care to elaborate in more detail? It seems like all black holes must spin, because motion is the norm in the universe, nothing seems static or stationary. But consider the conservation of angular momentum of a collapsed star. Like the example of a ice skater spinning with arms out, then when they bring their arms in their spin increases. What must happen with black holes? It must be far more of an effect. It seems like the spin would reach relativistic speed very easily.

Fascinating explanation of motion of the spiral arms, thanks Martin. Nice density waves Granpa. Anyone know how close we are to the nearest high-density spiral arm? When will we pass thru another arm and how close will our neighbor stars get to us when we do? I will try to look these up, unless someone knows offhand. When spiral galaxies collide does that mix them up so much that they either form irregular shapes or become ellipticals? Merged post follows: Consecutive posts merged Yes and the motion of density waves. I bet that if the SBH at the center of our galaxy is spinning that it is spinning in the same direction as the galaxy is rotating.

Take a look at wikipedia.org "black holes" which will answer most of your questions. Sure they may spin, in fact most of them must spin to conserve angular momentum of the star that collapsed. It is hard to imagine something with no volume spinning. What is spinning? The space and matter surrounding it. I recall that black holes may spin up to about 1,000 revs per second. I don't believe spin of the supermassive black holes (SBH) at the center of galaxies has anything to do with the galaxy's spiral shape. Can anyone explain why many galaxies have a spiral shape?

To paraphrase an earlier quote: "TV and radio signals don't reach very deep space, but at a distance they become so weak that they disappear in the roar of the electromagnetic noise." My question still stands. How far into space does SETI hope to be able to detect a narrow-band signal? Of course, laser detection would catch more distant signals. My other questions: Does SETI send a signal outward, so ETI can know about us? How far out do OUR unintentional radio and TV signals reach into space for ETI's to hear us? Are 100% of all UFOs simply mistake, delusion, or fraud?

Consider that SETI is searching for something that may be only accidentally broadcasted into space. Like the example in the movie "Contact" when we decoded a transmission from space and it turned out to be them bouncing back something from Earth a very early TV broadcast of Hitler giving a speech. Once an ETI achieves the ability to send radio or TV signals into space, they soon realize that they have nothing to gain by broadcasting themselves to outer space. I would like SETI to keep looking just in case. I may have the wrong impression of what they are capable of, and what is possible.

I agree that the basic assumption of SETI is that ETIs would have any reason to broadcast their position in space. What would any ETI have to gain by letting the galaxy know "Here we are! Come and do with us what you will."

To quote from the excellent story you attached: "The belief that an alien civilisation might also be listening to our television and radio signals has also been dashed by the recent discovery that the signals don't, as once thought, reach into deep space: they eventually become so weak that they disappear in the roar of the electromagnetic noise." Then how far into "deep space" do the SETI team hope to listen?

What does your Drake Equation yield? I heard Michio Kaku interviewing a guy working at SETI a couple of weeks ago on his radio program "Explorations". Did anyone catch that? They discussed the likelihood of detecting intelligent signals from nearby stars. The SETI guy, sorry I missed his name, said he didn't know how common intelligent life was, but within the next few decades the SETI search will either find ET(s) or conclude that they are not out there, or at least not transmitting. He was critical of the Rare Earth hypothesis, among other things, explaining how even it Earth had no moon the loose rotational axis would move so slowly that it would hardly pose a threat to early man. He finally and reluctantly gave his current assessment of the Drake Equation and gave his number of ETs, at least as intelligent as we are, as about 10,000 in our galaxy, and probably one within 1,000 light years from us.

That is what I mean granpa, there was too much angular momentum, and low density so very little gravity in the swirling expanding masses of gas and dust, for it to all just fall into the middle and become a SBH. The original eddys in the early big bang became SBHs.

When the universe became transparent, did the expanding mass of atoms have a color or just pure white light, of all wavelengths?

Nice info Widdekind, thanks for sharing. I understood you 100% this time. Let's be on the lookout for an entourage of stars following a medium massive black hole thru our galaxy. How do you think supermassive black holes originally formed? I seems to me they must have formed at the time of the big bang because how does that much matter, Millions or Billions of solar masses, get close enough together to create a SBH? Stars are too disbursed and have too much motion to all fall together like that.

Interesting news, thanks for that. According to wiki one gigaparsec is about 3.262 Billion light-years so one megaparsec is about 3.262 Million light years, or about 60% further from us than the Andromeda galaxy. I grew up using light years. Megaparsecs is not a familiar unit of measure to me and perhaps some others. Space is expanding at the rate of 74 km/sec every megaparsec. If expansion is accelerating, how long until the expansion rate is 75 km/second? Correct me if I am wrong, but using simple math we can calculated how far away this expansion adds up to light speed. That would be at 13.2 Billion light years away where the expansion adds up to light speed (300,000/74 km/sec = 4,054 megaparsecs = 13.216 Billion LY away), which coincidentally is near the horizon of the furthest visible galaxies or quasars. How can we detect the CMB radiation if it is expanding away from us at far beyond light speed? Merged post follows: Consecutive posts mergedTo answer my own question, we can now detect the CMB radiation because it left that region so long ago, when it was much closer to us, so that it had enough time to arrive here.

"...In Einstein Physics, as fast as you travel, as slow the time will be. If that is true, at the speed of the light, the time has stopped...." Time dilation only applies to matter's motion, not light's motion.

If black holes are like a connection with a higher dimension, then maybe that explains supermassive black holes. They exist in our universe because they originated in a parallel higher dimension and leaks over into our universe.

From the little I read about Superstring theory in Astronomy magazine, correct me if I am wrong, I think they said something like the Big Bang was the result of a collision of higher dimensions. I think it was like a couple of bed sheets handing on parallel laundry lines to dry in the sunshine. These flat sheets have only two dimensions of infinite size, and they represent two parallel higher dimensions that are very close together but not touching. The Big Bang was when they came together which might not be at a single point, but could have started from a region, or series of regions, of any size, then spreading outward in all directions? That would explain cosmic inflation?

I watched the video to hear what he said about how small the observable universe could have been early on, and I think he did say smaller than an atom, but I don't remember him ever using the word singularity, just as Martin said. It is hard to imagine 100 Billion galaxies compressed into an area smaller than an atom. That is beyond surreal! So is the word singularity only used for black holes?