RINOs an Endangered Species?
According to Wikipoo, et. al., the Northern White Rhinoceros (Ceratotherium simum cottoni) is a critically endangered species. Apparently two females live on a wildlife preserve in Sudan, and no males are known to be alive. So basically, this species is dead as soon as the females die of old age. Presently they are watched over by armed guards 24/7.
Biologists have been trying to cross them with the other subspecies, Southern White Rhinoceroses (Rhinoceri?) without success; and some genetic analyses suggest that perhaps they aren’t two subspecies at all, but two distinct species, which would make the whole project a lot more difficult.
I should hope if the American RINO (Parasitus rectum pseudoconservativum) is ever this endangered, there will be heroic efforts not to save the species, but rather to push the remainder off a cliff. Onto punji sticks. With feces smeared on them. Failing that a good bath in red fuming nitric acid will do.
But I’m not done ranting about RINOs.
The RINOs (if they are capable of any introspection whatsoever) probably wonder why they constantly have to deal with “populist” eruptions like the Trump-led MAGA movement. That would be because the so-called populists stand for absolutely nothing except for going along to get along. That allows the Left to drive the culture and politics.
Given the results of Tuesday’s elections, the Left will now push harder, and the RINOs will now turn even squishier than they were before.
I well remember 1989-1990 in my state when the RINO establishment started preaching the message that a conservative simply couldn’t win in Colorado. Never mind the fact that Reagan had won the state TWICE (in 1984 bringing in a veto-proof state house and senate with him) and GHWB had won after (falsely!) assuring everyone that a vote for him was a vote for Reagan’s third term.
This is how the RINOs function. They push, push, push the line that only a “moderate” can get elected. Stomp them when they pull that shit. Tell everyone in ear shot that that’s exactly what the Left wants you to think, and oh-by-the-way-Mister-RINO if you’re in this party selling the same message as the Left…well, whythefuckexactly are you in this party, you piece of rancid weasel shit?
Republicans won…in Virginia, and maybe in New Jersey, and in a lot of local races nationwide (including school boards–very critical in the long term).
If we can’t possibly win without an honest system, and we know the system has not been fixed…uh, what’s up? Seems like a bit of a contradiction.
So I will modify my stance somewhat, in the light of new information: Apparently the automated cheating that’s rather subtle could be overcome. And indeed it was overcome in 2020 as well.
That’s when the Left/Establishment went to good old fashioned blatant ballot-box stuffing, putting up cardboard to block the view into election centers and running ballot after ballot through the machines. To say nothing of the six figure dumps of votes entirely for China Joe and Skanky Hoe.
This time, for whatever reason, they didn’t go that far.
Perhaps it’s just so they can claim “See, Republicans can win elections, so we’re not cheating and Trump was just a Loser.” In which case, I’ll go back to my original stance and say that we cannot win until the election process is fixed. But then I’ll go on to add: unless they decide for tactical reasons to let us win a couple.
So for now, I’ll stick with:
Justice Must Be Done.
The prior election must be acknowledged as fraudulent, and steps must be taken to prosecute the fraudsters and restore integrity to the system. (This doesn’t necessarily include deposing Joe and Hoe and putting Trump where he belongs, but it would certainly be a lot easier to fix our broken electoral system with the right people in charge.)
Nothing else matters at this point. Talking about trying again in 2022 or 2024 is pointless otherwise. Which is not to say one must never talk about this, but rather that one must account for this in ones planning; if fixing the fraud in the system is not part of the plan, you have no plan.
This will necessarily be piecemeal, state by state, which is why I am encouraged by those states working to change their laws to alleviate the fraud both via computer and via bogus voters. If enough states do that we might end up with a working majority in Congress and that would be something Trump never really had.
Lawyer Appeasement Section
OK now for the fine print.
This is the WQTH Daily Thread. You know the drill. There’s no Poltical correctness, but civility is a requirement. There are Important Guidelines, here, with an addendum on 20191110.
We have a new board – called The U Tree – where people can take each other to the woodshed without fear of censorship or moderation.
And remember Wheatie’s Rules:
1. No food fights
2. No running with scissors.
3. If you bring snacks, bring enough for everyone.
4. Zeroth rule of gun safety: Don’t let the government get your guns.
5. Rule one of gun safety: The gun is always loaded.
5a. If you actually want the gun to be loaded, like because you’re checking out a bump in the night, then it’s empty.
6. Rule two of gun safety: Never point the gun at anything you’re not willing to destroy.
7. Rule three: Keep your finger off the trigger until ready to fire.
8. Rule the fourth: Be sure of your target and what is behind it.
(Hmm a few extras seem to have crept in.)
This week, 3 PM MT on Friday, markets closed for the weekend
Everything is UP. Gold has busted $1800. Silver has busted $24. I suspect they’re going to continue upward, for now.
The Distance Ladder
A couple of go-backs
A couple of things I failed to mention last time.
Schwarzschild (the name is German for “black shield,” ironically enough) did his theoretical work in 1915, immediately after Einstein published the theory of general relativity. His solution to the Einstein field equations of general relativity was the first one, in fact. Astrophysicists are still careful to distinguish “Schwarzschild black holes” from rotating black holes. Schwarzschild was killed in action on the Eastern Front in World War I.
There probably is no such thing as an actual non-rotating black hole. Such would have to be formed from a non-rotating massive star (or a nebula with absolutely no rotation, in the case of the supermassive black holes). Remember that even the tiniest rotation will be magnified, and magnified a lot, as the object shrinks down from light years (or tens of trillions of kilometers) across, to star-sized (hundreds of thousands of kilometers) to just a few kilometers in radius, just as the figure skater spins much faster when she pulls her arms in.
Black holes are generally safe…as long as you’re far enough away. If the sun were magically to be replaced by an equal-mass black hole, the Earth would continue in its orbit and not be sucked in. It’s only when you get to within about 3 Schwarzschild radii that you can’t have a stable orbit. (And the Schwarzschild radius is the radius at which the escape velocity is equal to the speed of light.) For the sun the Schwarzschild radius is 2,950 meters (not kilometers, meters). Earth could be made into a black hole too–if you could manage to compress it until its radius is 8.87 millimeters.
Astronomers can easily measure the direction of a star. This was being done with surprisingly high precision even before the invention of the telescope. As seen from earth, the sky forms a “celestial sphere” and every star’s position on that sphere can be measured and plotted in star charts. The celestial sphere appears to rotate on an axis (really it’s the earth that rotates on that axis, in the opposite direction), so that defines north and south “poles” on the celestial sphere; and halfway between them is the celestial equator. So you can get something like “latitude” on the celestial sphere, only it’s called “declination” or “Dec.” Longitude is trickier because there’s no objective zero point, but can be handled too. The sun, of course, moves along the celestial sphere following the “zodiac” which is a circle tilted at a 23.5 degree angle to the celestial equator (and again, it’s not the sun that’s really moving, it’s the earth orbiting the sun making the sun appear to move). The place where the zodiac crosses the celestial equator, when the sun is moving from the southern celestial hemisphere into the northern celestial hemisphere, is called “the first point of Aries” and is also the zero “longitude” point by convention. When you see a statement like “Spring will start at 4:46 PM on March 21″ that’s really the time the sun will (appear to) cross through the first point of Aries”. But here’s a wrinkle with regard to celestial longitude: It’s measured not in degrees but in hours. 24 hours makes up the full circle, then those are divided into minutes and seconds just like degrees are. And it’s called “Right Ascension” or “R.A.,” not longitude.
If you remember last week I posted a rather colorful plot of the orbits of some stars at the center of the Milky Way around the supermassive black hole there, plotted on a grid. The grid is marked off in seconds of arc (i.e., the kind of second that is 1/3600th of a degree, not the kind of second that is 1/3600th of an hour of right ascension), with respect to the declination and right ascension of that black hole. That is what those scales mean.
In any case it’s easy to measure this sort of thing; one of the two most manifestly obvious things about a star is what direction it’s in. (The other is how bright it is.)
But that alone will not tell us where the star is. In three dimensional space, you need three coordinates. In a Cartesian (square/cubic) grid, you need x, y, and z. In this case, you’re dealing with spherical coordinates, and you still need three of them (that’s why it’s “three dimensional” space): Right ascension, declination, and distance.
And unlike right ascension and declination, distance to a star is a cast-iron bitch to measure accurately.
I’ve told, here and especially elsewhere, the story of how we first determined the distance from Earth to the Sun (and hence all of the other distances within the solar system, since we already knew the ratios of the distances to each other). This was in the 1760s and it required observations of Venus transiting the Sun (i.e., crossing directly between Earth and the Sun so as to appear as a black dot crossing the fact of the sun, rather than crossing north/”above” or south/”below” the sun as it laps us in its orbit). This distance is called an “Astronomical Unit” (AU), and is currently defined to be 149,597,870,700 meters (in other words if we ever measure it in the future and it turns out the actual distance isn’t quite this, we’ll keep this number for the astronomical unit anyway). (And [Oh By The Way] knowing the average distance from the earth to the sun to the nearest 100 meters is, in and of itself, quite a triumph of measurement.)
With extremely painstaking measurements, best done on photographic plates, it became possible to measure distances to some stars once we knew this. It took until the mid 1800s. What happens is, as the earth revolves around the sun, its position changes by roughly 300 million kilometers, and that will cause nearer stars to appear to shift back and forth in relation to farther stars, just like you can shift your head back and forth and, say, a nearby light pole in a parking lot will appear to move back and forth with respect to the mountains in the background. (Folks in Kansas and especially Florida and Louisiana will have to adjust that example a bit.) This is known as parallax.
If you know how far you are moving your head, and can measure how many degrees along the horizon the pole appears to shift, it’s straightforward trigonometry to determine the distance to the light pole.
Even with the earth moving back-and-forth 300 million kilometers, the parallax of even the nearest star is less than one second of arc. (But note, this is quoted, for historical reasons, with respect to half of the earth’s orbital diameter, i.e., its orbital radius, which is to say, versus a 1 AU baseline, not a 2 AU baseline.) An arcsecond is about the width of a quarter at eighteen thousand feet (over three miles).
It’s possible to compute how far away something has to be to have a (half) parallax of one arc second as seen from a body orbiting with a radius of 1AU. Again, straightforward trigonometry. And, to the nearest meter (it has to be rounded because the formula has pi in it), it’s 30,856,775,814,913,673 meters. Or about 31 quadrillion meters or 31 trillion kilometers. This is called a “parsec” (short for “parallax-second”), and it’s roughly equal to 206,000 AU. (If you consider that Neptune’s orbit is roughly 30 AUs in radius, you can see how truly vast this distance is even compared to our solar system, which is measured in billions of miles. And this is closer than the nearest star.)
Astronomers–and I mean people who do astronomy for a living–think in and use parsecs. You’ve heard of light years, I am sure. That’s the distance light travels in a year. A parsec is actually about 3.26 light years, or alternatively, it takes 3.26 years for light to travel one parsec.
Astronomers talking to the public basically have to multiply everything by 3.26 so they can express it in light years. Why work in parsecs, then? Well, when they measure a parallax, they just have to divide it into 1 arc second to get the distance in parsecs. A 0.5 second parallax, means a two parsec distance, and so on.
The first successful parallax-based distance measurement was of the star Vega (visible low in the west shortly after sunset this time of year; it’s part of the Summer Triangle asterism); its parallax is almost exactly 1/8th of an arc second, so its distance was roughly 8 parsecs.
This was conceptually easy, but parallaxes were so small that by 1900 only 60 stars had had their distances measured. The process sped up in the early 20th century, to be sure…but since even with a small telescope hundreds of thousands of stars are visible, we weren’t going to finish off the list any time soon. Plus, of course, the fact that most of these stars are so distant they couldn’t be measured by the instruments of the time–they were in fact used as the backdrop for the nearer stars to move against. (Even today, with satellites doing the work, we really can’t get past about 1600 light years with this method.)
Clearly, if we were going to measure lots of stellar distances, we’d need another method.
But now for a wrenching change of subject.
The Shape of the Universe
William Herschel (1738-1822) is best known as the discoverer of the planet George. At least, that’s what he wanted to name it, after the King of England, George III.
(I’ll pause now and give you all a chance to quit vomiting at the prospect of naming a planet after that particular asshole.)
This name was not accepted by most astronomers, so instead they named it after every asshole: Uranus. And of course, that probably leads to even more bad jokes than naming it “George” would have. Astronomers school themselves to say “YER in us” instead of “your Anus” when they name that planet, but even that sounds too much like “urinous” (full or redolent of urine). Perhaps they should have gone with “OO rahn us,” probably closer to how the Greeks pronounced that name (father of the Titans) in any case. (And no, I didn’t mean to usurp Wheatie’s word of the day, but if you can find a good use for “urinous” with respect to current events–shouldn’t be that challenging–go right on ahead.)
Anyhow, Herschel did a lot of other things, perhaps the most important of which was discovery of infrared light. But for our purposes today, he was also the first to suggest that the stars, if their three-dimensional positions could be plotted, would form a disc with a central bulge, sort of like some renderings of flying saucers; and that the Sun would not be at the center of this shape.
How did he conclude this? If you get away from city lights (and that was easy to do in his day; nothing was as brightly lit back then as it is now), you will see a faintly glowing cloudy band stretching across the night sky. In fact, this cloudy band runs clear around the celestial sphere, including through the part we cannot see from the United States because it’s too far south. It’s most prominent where it runs through the constellation Sagittarius, but it also runs through Cassiopeia (the “W” in the northern sky) and the northern cross (part of Cygnus), in fact it runs along the long member of the cross. (This part of it should be readily visible shortly after dark…again, if you get the heck away from city lights.)
The ancient Greeks, of course, had spotted this band, and had named it γαλαξίας κύκλος (galaxias kyklos) or “milky circle” since the pale faint color suggested milk to them; they even had conjured up a myth that it was actual milk from the breast of Hera, queen of the gods. The Romans called it via lactea which translates directly to “Milky Way.”
When Galileo turned his telescope on the Milky Way, it turned out to be hundreds of thousands, if not millions, of stars that were individually too faint to be seen by the unaided eye, but together turned into this “milky way” stretching across the sky.
What Herschel had done was to catalogue thousands of stars and other deep sky objects, like nebulae, and to note that more of them were in the general direction of Sagittarius than any other direction, and of course most were in the plane of the Milky Way than other directions (such as 90 degrees away from it, where almost no stars are). And exactly opposite of Sagittarius, the Milky Way was thinnest.
That’s what we’d see if all the stars were spread out evenly in a fairly flat disc, and we were inside the disk but off center. We’d see the most stars looking through the center, lots of stars looking any other direction through the disc (the least when looking away from the center, because the distance to the edge of the disc is shortest in this direction) and much less looking perpendicularly to the disc.
The Milky Way is not just brighter in the direction of Sagittarius, but broader, which is why Herschel believed (correctly) there was a central bulge in that direction.
Note that Herschel was working before we could measure the distance to stars (and well before spectroscopy and stellar classification), so he was going entirely off their brightness, assuming that dimmer stars were further away. However, he was still essentially right about the shape of this conglomeration of stars.
It was believed that everything–the entire universe–was within this structure. That included not just stars, but also nebulae, in essence either dark, opaque clouds of gas and dust, or in some cases such clouds brightly lit by nearby stars.
One fairly obvious and prominent nebula is in the sword of Orion; it looks a bit fuzzy to the unaided eye (instead of being a crisp point of light like other things “up there”) but in binoculars it is obviously a glowing cloud of gas lit by stars embedded within it.
In fact, this is a place where stars and planetary systems are forming–right now. This is abundantly clear from observations, including from Hubble Space Telescope images.
Other nebulae had distinctly spiral shapes, like, for instance, this one:
And this is pretty much where things sat, clear into the early part of the 20th century. The universe was believed to consist of the Milky Way, surrounded by empty space.
But there were proponents of a different idea, that these spiral nebulae were actually separate galaxies. On April 26, 1920, in fact, there was a debate held at the Smithsonian’s Museum of Natural History; today it is known as the “Great Debate.” Harlow Shapley argued the spiral nebulae were on the outskirts of this galaxy, while Heber Curtis argued that they were in fact, distinct galaxies and therefore very far away, outside of this galaxy.
Note that this was just over a century ago. The issue wouldn’t be settled until 1924.
We have only known about other galaxies definitively for less than a century. Think about that.
How could the people who thought that “spiral nebulae” were in fact separate galaxies outside our own actually prove it? Or alternatively, be made to shut up? Well, the most straightforward way to do that would be to show that they were far, far away–or not.
Which brings me back to pointing out that in astronomy, measuring distances is a cast-iron bitch.
Even with today’s satellite technology, we can barely get parallaxes over 1% of the distance across this galaxy; certainly in 1920 using stone knives and bearskins we’d never be able to prove something was outside the galaxy with parallaxes.
A Standard Candle
But we already had a solution to this.
We go to HAH-vuhd, 1908-1912, and yet another woman, Henrietta Swan Leavitt (1868-1921).
I point out the fact that she was, indeed, a “she” because in those days it was very unusual for women to be involved with the “hard” sciences. How, then, did so many of them end up clustered at Harvard?
As it happens the astronomer Edward Charles Pickering (1848-1919) had developed a method of taking the spectra of multiple stars all at once by putting a prism in front of a photographic plate. He had,over decades, assembled a team of women to go through the data for 220,000 stars. This was primarily because they were cheap labor, but also because even back then women were appreciated for work that required attention to detail. [For instance, the US Mint preferred women for work as adjusters, who’d file excess precious metal off of unstruck planchets.] Annie Jump Cannon, whom we’ve met previously, emerged as their natural leader. The group became known as “Pickering’s Computers” (this was well before the invention of the electricity powered computer) and are now known as the Harvard Computers. They didn’t have doctorates (not by any means) but their contributions to astronomy today are well-regarded.
There were so many photographic plates involved–and back then these were sheets of glass coated with emulsion–that Pickering’s research was said to weigh 120 tons.
Cecilia Payne-Gaposhkin (whom I discussed previously; she discovered the stars were mostly made of hydrogen) was not one of the computers; she actually was a graduate student who worked closely with them.
Henrietta Swan Leavitt, on the other hand, was one of the computers and she established the first “standard candle.”
Clear back in September of 1784, Edward Pigott noticed that the star Eta Aquilae was variable; it would regularly dim, then brighten suddenly, then dim again. It would do so with the same period; every pulsation took the same amount of time, known as the period. (We now know that stars like this actually pulsate in size, like a yo-yo dieter only much more rapidly.) Just a few months later a different astronomer noticed the same for Delta Cephei. The periods range from a few days to a few months.[A digression about these names. There are thousands of stars in the sky visible to the naked eye; countless more visible with a telescope. They can’t all be given unique names (though hundreds have been, everything from Betelgeuse [famous] to Zubenelschamali [not so famous]). So in 1603, just before the invention of the telescope, Johann Bayer came up with a system of labeling the brightest star in a constellation as “alpha” (such as Alpha Orionis–Betelgeuse). Beta would go to the second brightest star and so on. This would be followed by the Latin genitive of the constellation name. So Betelgeuse was “Alpha of Orion,” strictly translated. This is called the Bayer designation, and has been extended since then. Continuing to look at Orion, alpha through kappa, the brightest ten stars: Eight of them have “real” names, one (theta) is actually the Orion nebula, and eta is (as far as Wikipoo knows) nameless. The three belt stars are among the named stars, the four stars of the not-quite-a-rectangle also all have names. Returning to Cepheids, Delta Cephei was designated the fourth brightest star in Cepheus by Bayer.]
There turned out to be an entire class of these variable stars and they became known as Cepheid variables in honor of Delta Cephei. Several dozen had been discovered by the end of the 19th century. Today we know that they are typically stars four to twenty times as massive as the sun, and therefore very bright, up to 100,000 times as bright–but this was not apparent before Henrietta Swan Leavitt studied them.
In 1908 Henrietta Swan Leavitt began measuring the apparent brightness and periods of numerous Cepheids in the Small and Large Magellanic Clouds. Apparently there are thousands of Cepheids in these clouds, though they appear quite faint compared to the ones previously discovered.
The SMC and LMC are patches of milkiness that are quite apparent to the naked eye, provided you are far enough south; they are deep in the southern celestial hemisphere, and the further south an object is, the further south you have to be for it to be above the horizon. The Large and Small Magellanic Clouds were noted by Antonio Pigafetta, who was with Ferdinand Magellan on his voyage (yes, that Magellan, famous for being the first to circumnavigate the Earth in the early 1500s). Of course many had noticed them before, anyone from Australian aborigines to Arabic astronomers and some other early European explorers, but for some reason this guy was able to tell the European scientific community about them and have it “stick.”
Leavitt noticed that the Cepheids in the Magellanic Clouds had an interesting correlation: the brighter they appeared, the longer their periods.
It was logical to suppose that Cepheids in one of the clouds are all at about the same distance from us. Which would mean the brighter ones really were intrinsically brighter than their dimmer cousins. And if the brighter ones had the longer periods…well then!
So what we had was a “standard candle” (Leavitt coined the term), in other words something of known intrinsic brightness. If you could measure the period of a Cepheid, and it had a long period, you knew it was the same intrinsic brightness as one with the same period in the Large Magellanic Cloud. If it looked dimmer, then it was actually further away. If it looked brighter, it was closer. So you could tell the (relative) distance of a Cepheid by measuring its period.
Leavitt published in 1912.
All we needed now was to measure the distance to one Cepheid variable by some other means and we’d know the distance to all of them. Eijnar Hertzsprung (as in “Hertzsprung Russell Diagram”, 1873-1967) measured the distance to several Cepheids by parallax in 1913.
We had our standard candle and were off to the races now.
In 1924, Edwin Hubble (after whom the space telescope is named, 1889-1953) working at the Mt. Wilson observatory in southern California, was able to detect very faint Cepheids in many of the “spiral nebulae,” measure their periods, determine that they were well outside the bounds of “the” “one and only” galaxy, and could therefore establish, once and for all, that the spiral nebulae they were in were actually separate galaxies.
The universe had just gotten bigger. A lot bigger. Some of the galaxies Hubble was able to measure were sixty or so million light years away; which is to say six hundred million trillion kilometers away (which is to say six hundred quintillion kilometers). That’s a lot more than the 100,000 light year diameter of this galaxy, which hitherto had been thought to be the entire universe.
A bunch of those galaxies about fifty or sixty million light years away are in the constellation Virgo, and that group is now known as the “Virgo cluster.”
And there were many, many dimmer “spiral nebulae” in which no Cepheids could be detected at all–presumably because those nebulae were so far away the Cepheids in them were too faint to see. So how big, precisely, is this universe of ours? Certainly at least hundreds of millions of light years!
At the other end of the scale, and most famously, there is a “spiral nebula” in Andromeda. You can see it with your own unaided eye, far away from city lights. (I personally find it hard to see; I have to look away from it slightly to see it. But it certainly shows up in binoculars!) It’s now called the Andromeda Galaxy, thanks to Hubble. It’s about 2 million light years away. The LMC and SMC are much closer, they’re now considered satellite smaller galaxies in orbit about our own galaxy. There are a few other very close galaxies, such as M-33; together with the Andromeda and Milky Way galaxies they make up the imaginatively-named “Local Group.” Twenty quadrillion kilometers may not seem terribly “local” to you, but for galaxies, that’s Standing Room Only and get your elbow out of my eye!
That telescope on Mt. Wilson? It was a monster in its day, with a 100 inch mirror. It still exists today; you can see it on tours during the daytime. It is not, however, used by professional astronomers any more as it’s simply not powerful enough. However, for several thousand dollars a night, you can rent the telescope–though as far as I know that opportunity is only extended to astronomy clubs.
But in terms of its historical impact on our view of the universe, it is probably second only to Galileo’s telescopes. Hubble himself is considered a Giant of astronomy; those astronomy clubs can actually use the same telescope he used.
But Hubble was not done in 1924. If anything, what he went on to do after this was even more important.
Vesto Melvin Slipher (1875-1969), had, back in the 1910s, looked at “spiral neblulae” through a spectroscope and had been able to measure their velocity towards or away from us (the “radial” velocity) by noting the Doppler shift of the spectral lines.
Almost all of them were moving away from us, as indicated by a shift towards longer wavelengths (lower frequencies). This is the famous “red shift” because the lines in the visible spectrum were shifted towards red, the longer wavelengths of visible light. Very few were shifted towards violet (which, for some reason is called a blue shift, not a violet shift). This was peculiar; after all a bunch of objects “out there” should have a pretty random assortment of radial velocities…yet almost all of these spirals were moving away from us, and rather rapidly, too.
For example, M-87 in the Virgo Cluster (this is the one with the really big black hole at its center–but Slipher had no idea about that) is moving away from us at 1284 kilometers per second. Which is pretty doggone fast.
Hubble took this data, combined it with his distance measurements, and made a plot.
And got the surprise of his life.
It turns out that the farther away a galaxy is, the faster it is receding, The main exceptions turned out to be within the Local Group; some of those galaxies actually are headed towards us (like Andromeda, which will collide with this galaxy in about five billion years).
M-87 is 16.4 megaparsecs (million parsecs) away from us which puts it at about 53.5 million light years off.
What is it about the Milky Way galaxy that is repelling almost all of the other galaxies?
Nothing, actually. It turns out that a hypothetical observer in any galaxy will see all of the other galaxies rushing away from him, the further away, the faster.
Hubble was able to determine that for every megaparsec of distance, a galaxy is going to be moving 500 kilometers per second. As it turns out, there were significant problems with using Cepheid variables–it turns out there are two distinct classes of them that behave differently. I’ve ignored that fact up til now. But now, this recession rate is known to be 74 km/second…for each megaparsec of distance. This is known as the Hubble parameter, now. And the fact that further galaxies recede faster is now known as Hubble’s Law.
But, run the movie backwards! What happens? Since galaxies twice as far away move twice as fast, if you run the movie backwards, all galaxies come together simultaneously at some point. Which means (if you halt the reverse at this point and start looking at it in forward motion) everything was in one place, then there was a big explosion (or something like that) and all of the pieces got blown away from from the other pieces at some point in the distant past, eventually leading to what we see today.
Time for Einstein and Company to step in.
One thing that was instantly apparent to Albert Einstein when he formulated General Relativity was that it could be applied to the universe as a whole. Einstein believed (as most did in 1915) that the universe was essentially static and unchanging on a large scale. What we see now was pretty much what had been there…back forever.
However, both General Relativity and Newtonian gravity said that if the universe consisted of a bunch of stationary objects, they’d simply attract each other and start to move closer to each other, in exactly the same way that a stationary apple a meter above the floor will, without support, fall.
So Einstein, believing that this wasn’t what was happening (he really didn’t have evidence of that; this was before Hubble), put a fudge factor into his equation, a cosmological constant repulsion that counteracted what would otherwise be the natural inclination of the universe to contract.
Hubble’s discovery was an attitude adjuster for Einstein. The universe was not static and unchanging, it had not always existed. It had instead had a beginning, and from that beginning everything rushed apart. Clearly, ever since then, the galaxies had been slowing down due to their mutual attraction, but also, clearly, they hadn’t come to a halt. With the residual motion evident even today, there was no need for the cosmological constant fudge factor in his equations.
Einstein later considered it the biggest mistake of his life and he was probably right because he didn’t vote for Joe Biden.
[I say that, but perhaps a check of the voter rolls for Princeton, NJ is in order.]
In 1922, Alexander Alexandrovich Friedmann (1888-1925) worked with Einstein’s General Relativity equation, and derived a relationship between the average density of the universe (in kilograms per cubic meter, for instance–and by the way this number is very, very small!), its current expansion velocity, and its acceleration; this equation could be used to determine the future state of the universe (or any past state). You could essentially get the Hubble parameter out of it with the right inputs; and the equation can be rearranged to use the Hubble parameter as one of its coefficients.
The equation makes it clear that the Hubble parameter is not a constant, it can change. And indeed it’s expected to start out at a high value when everything was bunched together, then drop as things slow down over time as galaxies attract each other–exactly the way an apple thrown up into the air slows down and stops.
Another part of the equation is an expression for how fast the Hubble parameter is changing with time.
The big unknown, actually, is the average density of the universe. There is a certain value of it, which will cause the universe to expand forever, but as the time goes to infinity the speeds drop to zero…as if everything were currently moving exactly at escape velocity. This is the critical density, and the actual density could conceivably be one billionth (or a centillionth) of that value, or a billion times as much.
Determining the ratio of the actual density to the critical density has occupied a large part of the efforts of cosmologists over the last century. I had originally written a bunch more on that here…but this article has gotten long enough, and I don’t want to get too historically askew. Suffice it to say that early estimates were less than 1, but more than 0.01, meaning that there didn’t appear to be enough matter in the universe to cause its expansion to slow down and have it recollapse. But these numbers are suspiciously close to 1 when you consider the range of conceivable values is literally infinite.
It appeared at the time as though it was one third of the value, which is close enough to 1 (compared to all of the other possible ratios) to make scientists suspect it really is 1 and we’re just not measuring it right.
But this is general relativity we are dealing with here, not Newtonian mechanics, so the Friedman equation is actually an equation about how much space time is warped. That makes it more than just an equation about escape velocity. And so there are some things about it that are distinctly counter-intuitive.
First off, the galaxies that rushed away from the original point location are not moving through space. Instead, space itself is expanding. Originally, space itself was small; as it expanded all the matter in the universe stretched out with it, and eventually coalesced to form galaxies. (If the galaxies started moving in some different direction after the Big Bang, because they were near some giant cluster and are attracted to it, that’s actual motion. (And today we believe the Milky Way is moving towards the Virgo cluster.)
One consequence of space expanding is that the red shifts that we see are actually due, not to a Doppler effect but rather, to the fact that while the photon was travelling from the distant galaxy to our eyes the space stretched, which stretched the photon into a longer wavelength. One rather odd consequence of this is that a photon, once emitted, will lose energy as it travels through intergalactic space because its frequency is dropping.
Second, space-time across the expanse of the universe has a shape. And it turns out that a value of density lower than the critical density would imply that space has negative curvature, and a value that is higher would imply that space has positive curvature.
Now what the heck does that mean? How can space be curved? Well, we already know it can be warped and that’s what gravity actually is. But this deserves some elaboration.
You were taught in geometry class that the sum of the three interior angles of a triangle is always 180 degrees. That’s a fundamental property of flat space.
But really, this is only true if the triangle is drawn on a flat plane.
If you were to travel from the equator directly to the north pole, make a right-angle (90 degree) left turn, then head back to the equator (traveling south), then, on reaching the equator, make another right-angle left turn (now traveling east), you’d end up back where you started, eventually. You could then turn left 90 degrees and be facing north, like you were in the beginning.
You’ve drawn three straight lines, and are back where you started; that’s a triangle. But every interior angle is 90 degrees so the total of the three is 270 degrees.
This “breaks” that 180 degree rule I just reminded you of, but the earth is not flat, it’s (roughly) spherical. It exhibits positive curvature.
Now imagine a surface like a saddle or a Pringles chip, extended to infinity. (The bell of a tuba also works.) Drawing a triangle on that kind of surface gives you a sum of interior angles less than 180 degrees.
If the universe has too high a density, its expansion will eventually cease (at a time short of infinity) and it will collapse back in on itself again. This would render space-time the four dimensional equivalent of a sphere.
If it’s below the critical density, then even at infinity there’s velocity left to the expansion, and space time is shaped somewhat like that saddle.
If it’s exactly at the critical density, then space time is, on the whole, flat.
How can we tell? Try measuring the interior angles of a really big triangle. Preferably one billions of light years in size. (And believe it or not, today’s scientists think they’ve actually done something like that, and they believe the universe to be flat. But I am WAY ahead of the story here.)
If this makes your head hurt, you’re not alone, believe me.
Anyhow, to return to our narrative, a lot of astronomers did not want to accept that the universe didn’t have a definite beginning. Fred Hoyle, famously, refused to accept it, and died in 2002 still refusing to believe it.
It’s not that he didn’t believe that the galaxies were rushing away from each other, but rather, he imagined that as galaxies grew further apart, new matter in the form of hydrogen atoms was being spontaneously created, which would then coalesce to form new galaxies. This would result in the universe of the distant past, or the distant future, looking about the same as it does today, rather than the galaxies being closer together, or further apart, respectively. This is known as the steady state theory, and from what I can see, virtually no scientist accepts it today. Certainly, we’ve never detected any sign of hydrogen spontaneously being created throughout space, as it would have to be if Steady State were true.
Hoyle, trying to characterize the theory he disagreed with so vehemently, came up with the moniker “Big Bang.” He claims he wasn’t trying to be derisive, but many took it as such. The proponents proudly adopted the term to describe that instant–roughly 11 to 13 billion years ago–when everything in the universe was jammed close together.
(It’s not as if people haven’t, at other times, proudly adopted what was supposed to be a derisive label. Right, oh fellow Deplorables?)
The Big Bang theory was simultaneously worked out by Georges Lemaitre (1894-1966), who was not only an astronomer, but also a Catholic priest. He certainly had no problem with the universe having a beginning! In fact Hubble’s Law is often called the Hubble-Lemaitre’s Law.
There was one minor issue though.
Running the tape backwards, the Big Bang appeared to be ten or eleven billion years old. This was based on extrapolating the current expansion rate backwards, and accounting for how the expansion rate was undoubtedly faster in the past. Yet we also had good reason to believe that globular clusters–groupings of thousands to millions of stars that mostly exist above and below the plane of this galaxy–are at least 13 billion years old. Clearly it’s absurd that globular clusters could be older than the universe that they are part of, so this was a nagging issue for quite some time.
The Next Rung Of The Ladder
With Hubble-Lemaitre’s Law established, we had a new way to measure distance. If we couldn’t see Cepheid variables in some galaxy because it was too far away from us, we could instead measure its red shift, turn a mathematical crank, and get a distance out, one likely to be over a hundred million light years.
In fact, when quasars were first discovered, their red shifts were measured and they were instantly some of the most distant objects ever detected. Some were even billions of light years away. But there is a complication here. The farther away a galaxy is, the further back in time we are looking. If we look at M-87, we are seeing it as it was 53 million years ago, because the light has traveled 53 million light years to get to us, and for the light to be getting to us now, it has to have left M-87 53 million years ago.
Similarly for more distant galaxies. As our telescopes became more and more sensitive, we were looking at galaxies further and further into the past. Quasars, it turns out, all happened well in the past, and now we know they are a “young galaxy” thing as the black holes at the galactic centers devour interstellar gas. In older galaxies, that interstellar gas is as gone as last Thanksgiving’s dinner.
But, if the universe has been slowing down its expansion rate, 53 million years ago, or a billion years ago, the Hubble parameter must have been higher. If we compute a distance to a galaxy using a constant Hubble parameter, we’re introducing an error.
Of course this relies on what is ultimately an assumption: That the Hubble parameter is indeed decreasing. It’s an assumption that seems to make sense, because after all everything in the universe is being attracted to everything else. On the other hand, if you’re a galaxy surrounded by other galaxies, their pulls should all cancel out, and that same is true of all of those other galaxies too–they’re all surrounded by other galaxies.
So scientists wanted to check that assumption–and the data gathered would help nail down the average density of the universe a bit better.
So we needed some other way to measure the distance to a galaxy, and compare it to the distance inferred from its red shift. If the first distance was further, that would imply that the Hubble parameter used to be bigger than it is today (as expected) and we could even, if we did this with enough galaxies with different red shifts, be able to plot how much the Hubble parameter was at any given time in the past.
But to do that, we needed another “Standard Candle,” one a lot brighter than Cepheid variables.
And we eventually found one.
But here, I think, is where I need to pause.
I’m going to shift gears next time. But not really. Because as you investigate the very earliest stages of the universe (I am talking about, say, 1 second after the Big Bang) you find yourself needing to know about particle physics.
So switching from talking about the entire universe, to talking about stuff much smaller than atoms, isn’t as jarring as it might seem at first.
Obligatory PSAs and Reminders
China is Lower than Whale Shit
To conclude: My standard Public Service Announcement. We don’t want to forget this!!!
Remember Hong Kong!!!
Zhōngguò shì gè hùndàn !!!
China is asshoe !!!
China is in the White House
Since Wednesday, January 20 at Noon EST, the bought-and-paid for Joseph Biden has been in the White House. It’s as good as having China in the Oval Office.
Joe Biden is Asshoe
China is in the White House, because Joe Biden is in the White House, and Joe Biden is identically equal to China. China is Asshoe. Therefore, Joe Biden is Asshoe.
But of course the much more important thing to realize:
Joe Biden Didn’t Win
Qiáo Bài dēng méi yíng !!!
Joe Biden didn’t win !!!