Goodbye Betelgeuse?

About five nights ago, I stepped outside, to take a look. That is, up. It's a habit, formed, long ago as a young, budding astronomer (and, 'Rock Star' Drummer...well, never mind about the 'rock-star' drummer part), but - any time that the night sky is clear of clouds - and I know about it - I do a "status" check; just, making sure that, "everything's there - and, things are the way they're supposed to be". Kind of like looking in on your kids, long after they've gone to bed...

While I'm out there, I do a sub-conscious, magnitude comparison, between the stars of the constellation, 'Orion' - a relative, close, loosely-grouped gathering of red and blue, 'super-giant' stars, out here at our 'end' of the galaxy. Throughout my entire life - the stars, "Betelguese", and "Rigel"; the 'right shoulder', and 'left foot', respectively; of the Hunter, Orion - have always appeared to be close in brightness, with the blue, Rigel, out-shining the red, and somewhat variable, Betelguese - by just a few "points". Every night. Every year. Always the same - my whole, life-long, life...

...but on the night of 21 DEC 2019 - something was, very, very different. Indeed -- things were NOT, the way, they were supposed to be.

Betelgeuse is generally the eleventh-brightest star in the night sky and the second-brightest in the constellation of Orion. Image by Muir Evenden on Insight Observatory's 16" f/3.7 astrograph reflector (ATEO-1).

The 'ancient's', had understood the stars to be, 'immovable', 'invariable', and 'eternal' objects. No one could blame them; the distances to the stars - any star, even the very closest - is an unfathomable number of miles away from 'us'. (24,900,000,000,000 - to be exact). Any motion through 3-dimensional space goes undetected; although the stars, *are* moving through space, in their long trip around the galactic core of the Milky Way galaxy (that's ours), they are so distant that their motion is not perceptible to us, here on Earth - and, not to the ancient's, either. Compared with the rest of the universe - we just live at a 'fleeting' pace, but the truth is - the stars do move. And change; sometimes, catastrophically.

The stars of the Orion group are, in fact, a relatively, loosely-grouped, 'open cluster', in which, the grouping is moving through space, together, as a whole, around the galaxy. The group is between, about, 500 to 900 light-years (LY) distant. That's pretty close, by cosmological standards, and accounts for their relative brightnesses, being so high, compared with most other stars. These blue-white beauties are some of the brightest stars that can be seen from Earth - just a bit dimmer, than the brightest star, 'Sirius', which happens to lie very nearby. In fact, if you walk outside, on any, clear, winter night - the brightest stars that you will see will be those of the Orion group.

Astronomers have learned much about the 'Orion group', also known as the 'Orion OB-1 Association', over the decades. They are, distinctly, set apart from the other stars in our, somewhat, limited field of view, in that, quite a few of them are extremely large, bright stars, of a type of star, called a 'super-giant'.

Well, 'So what!?'

OK, well - *here's*, "what": beginning with a 3-star asterism that most people are acquainted with - "Orion's Belt", those three stars are part of the Orion OB-1 Association. The left-most star in the belt, 'Alnitak', is a blue type, supergiant, at 800 LY distant - Alnitak shines in at a monstrous - 100,000 times - brighter than the sun! That's because it is 40 times the diameter of the sun!

The next star, the 'center' star of Orion's 'belt', 'Alnilam', another, blue supergiant, is 375,000 times as bright as the sun. That's because it is 84 times the sun's diameter. The last, or 'right-most' star in the belt, 'Mintaka', is 36 times the diameter of the sun, and blares in at 90,000 times the output of the sun. Another blue supergiant.

The constellation Orion the Hunter - Illustration Credit: Earth Sky and The Atacama Large Millimeter/submillimeter Array (ALMA) captured this image of Betelgeuse, revealing its lopsided shape and a huge bright spot. ALMA (ESO / NAOJ / NRAO) / E. O’Gorman / P. Kervella

Most of the stars that you see, up there, in the dusky grey (it is not black anymore, where I live), are older, dimmer, and somewhat redder stars than these 'Mavericks' of Orion. Supergiant stars are stars that are on their way out. They have near the end of their time on the main sequence, drifting toward oblivion, but, one star out of this group, has aged much faster than the others. And it is, now, visually, very obvious.

The red supergiant, "Betelguese", is now, about ten times, less bright than I remember it as a kid. And it's dimmer, now, than it was, the last time I saw it, just over a year ago. The great, red, supergiant is now at the end of its lifespan. The constellation, "Orion", has changed.

The once, bright, red star, has begun to shrink, inward, toward a collapsing core. Having burned through all of its original hydrogen mass - and its converted, helium mass, it is in the process of fusing its remaining elemental composition, all the way down to iron. Once it has reached this stage, its thermal, expansion energy will no longer counter the energy of gravity, and it will collapse - blowing itself, in a crescendo of blazing light, metals, and x-rays -- to smithereens. It will leave behind, a cold, dead, neutronic core.

Betelguese, is now, ready to do just that.*

*It is difficult to know, exactly, when a star is going to actually go supernova. That could happen, anywhere, from - tonight - to a few more, thousand years. But, it could be - tonight!

Dale Alan Bryant
Senior Contributing Science Writer

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The Telescope, and the Center Of The Universe

In the beginning, there was "us" - and, just us. (So we liked to think)

(fast-forward a few hundred thousand years...)

Around the Middle Ages, it was discovered that we inhabited a "world" - a round, spherical one. And so now, we and our world were all that there was.

But, a little later, in 1610, a physicist named Galileo Galilei, using a new and revolutionary optical instrument called a "telescope", discovered that the moon, Saturn, and Jupiter - were not just dots of light in the sky, but rather, they were, actual, "other" worlds. Not only were Jupiter and Saturn planets, in their own right, but they possessed satellites, as well. Galileo, and then others, noticed that these satellites were orbiting around their host planets - resembling miniature Solar Systems.

None of this new and revolutionary information would have been revealed, had it not been for a new and revolutionary instrument - Galileo's hand-made, tiny, 2-inch diameter instrument - the refracting telescope. (This new revelation caused a lot of problems - both, for Galileo, and for society, in general - because, just maybe - there were "others" on these "other worlds")

While Galilei did not invent the telescope, he very successfully built one and used it for astronomical observations. This image shows two telescopes in his possession. Image Credit - DPA-Picture Alliance.

In 1783, amateur astronomer, William Herschel, made the discovery that all of these "other worlds", were, actually, a conglomeration of worlds - an "island universe", which we, today, call the "Milky Way" galaxy. Using one of his - very large, for the day (40") - reflector telescopes, Herschel was able to, roughly, determine the general shape of the "Milky Way" (something like a double-convex lens, or, the way I like to imagine it: two, inverted Frisbees!). It was apparent then that, we reside in some, isolated structure of stars, and we named our isolated home galaxy after the dim band of cloud-like light that splits the sky into two "hemispheres". (This band of diffuse light, or the "Milky Way", can still be seen from some places in the world, so I understand).

William Herschel's sketch of the Milky Way Galaxy.

Sometime later, comet-hunter, Charles Messier, using his own, small, hand-made reflecting telescopes had found that the sky contained, seemingly, hundreds of small, cloud-like patches of light, similar to the milky band that circled the sky - ranging in size, up to, just larger, than the full moon. It was thought that these tiny "fogs", were just that - some type of cloudy matter, nearly, randomly distributed about the sky. All that Messier knew, was, that they were not the "comets" he was searching for. And so, they stayed, just fogs.

Then, in the 1920s, a debate took place, now known historically as the "Great Debate", on the nature of these luminous patches of fog. The debate focused on whether these structures were portions of our own galaxy, or, whether they were external structures. Around that time, a slightly pompous - but, generally brilliant astronomer, Edwin Hubble, had made another revolutionary discovery that ended the debate, altogether - these luminosities in the sky were not cloudy in nature. Hubble was able to resolve these hazy patches into individual stars, using the Hooker telescope. It turned out that they were actually, distant "island universes" (galaxies) in their own right!

In a spectroscopic analysis of the motions, of the millions of other galaxies that lie beyond our own island galaxy, the Milky Way - nearly the entire mass of the universe is receding into the distance - i.e. apparently, away from us. What's more, the velocity of any given galaxy's recession, is proportional to its distance - i.e., the farther away the galaxy is, the faster it is receding into the "background"! This situation is what produces, what's called, the "red-shift effect" - light's, own version, of sound's, "Doppler" effect. The result is that the spectra of those receding galaxies are shifted towards the red (longer wavelength) end of the visible light spectrum; in the same way that the tone from, say, a passing vehicle's horn, in a fluid, continuous way, drops in pitch as it passes by us and on to a direction that carries it farther away from us.

All of this is due to the general expansion of the universe, as a whole (hence, the "Big Bang", or, "Great Expansion" event, when began universal expansion). This condition was discovered by Edwin Hubble, back in 1929. It was his observations, now, using the 200" reflector at Mt. Palomar that revealed that the universe was in a general state of expansion. Only, a very few galaxies, appear not to be receding from us. This includes the 25 or so, member galaxies of what is called, the "Local Group", of relatively nearby galaxies, and the two satellite galaxies of the Milky Way galaxy, called, the Large, and the Small "Magellanic Clouds" (the LMC, and SMC, respectively), as well as the next, nearest, large spiral galaxy similar to our Milky Way galaxy, the Andromeda galaxy, or, M32. That galaxy is so nearby, cosmologically speaking, that it can just be detected in a clear, dark sky with the unaided eye. The galaxy lies in the constellation of Andromeda and it is a prime target for astrographic imaging, or, astrophotography.

But, from our own galactic island, it appears as if the Great Expansion event, itself, took place at the position of the Milky Way galaxy! And to make matters worse - this expansion is undergoing an apparent acceleration - one that increases, proportionally, as its distance from the Milky Way! Could it be that we are in some, privileged location, in relation to the rest of the universe? Can this really be so?

(I was going to have some fun with this, but I won't!)

The answer is, of course: No, it can't.

From the beginning of human civilization, man has revered himself to be the pinnacle of creation - whether he placed himself at some, centralized position, either on the Earth, or whether he placed the Earth, itself, at the center of - at first, the Solar System, and then the Milky Way galaxy - both of which were dead wrong. By small gradations, he has slowly discovered that there is no true center to the universe, nor is there any, true, up or down. Today, we know that our "island universe", is only one of the billions of other island universes - revealed to us, by the power of an inherently, very simple, optical marvel - the telescope.

Because of the telescope - we've not only revealed the nature of particular objects in the universe but also, general ideas as to the nature of the universe, on the whole.

Dale Alan Bryant
Senior Contributing Science Writer

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The Most Incredible Photograph Ever Taken

Yes - I have given this title, to the Hubble Ultra-Deep Field image, taken by the Hubble Space Telescope, just a few years ago.

Why?!

Think about this: take a look at any one of those colorful, oval "smudges", within the image, and enlarge it, to its maximum, reasonable resolution and magnification on your device.

Each one of the "oval smudges", is a galaxy of stars - just like our Milky Way galaxy!

Our galaxy contains, roughly, 300,500,000,000 stars, including our sun ("Sol") - a typical, standard, type G2, yellow-dwarf star - the kind of star that are a dime a dozen in any spiral galaxy.

Hubble Ultra-Deep Field - Image Credit: NASA, ESA S. Beckwith (STScI) and the HUDF Team.

Each one of the galaxies in the image also contains a comparable number of stars, planets, comets, asteroids, silicate and metallic specks of dust, and various, volatile gases.

Who knows?? -- how many other beings, in how many other galaxies, hosting, how many other suns, that have, how many other planets in orbit around them -- that, accommodate living beings, just like planet Earth -- just, might be looking right back at us!

THAT'S why!?!

Dale Alan Bryant
Senior Contributing Science Writer

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