This is the Classical Astronomy Update, an email newsletter especially
for Christian homeschool families (though everyone is welcome!) Please feel free to share this with any interested friends.
Why do the heathen rage, and the people imagine a vain thing? The kings of the earth set themselves, and the rulers take counsel together, against the Lord, and against his anointed, saying, Let us break their bands asunder, and cast away their cords from us. He that sitteth in
the heavens shall laugh: the Lord shall have them in derision. -- Psalm 2:1-4 IN THIS UPDATE The Blaze Star Hello Friends, I'm happy to announce the NEW Classical Astronomy website with a more updated style for nowadays. Still some cleanup and additions yet to be done but you can get the basic idea. Hoping to spend some more time
with the site and the content in the future. The new site is designed to attract other prospective readers besides homeschoolers. Since Classical Astronomy includes the natural techniques of telling time and finding direction from the Sun, Moon and stars, hoping that homesteaders, preppers, boaters, and outdoorsmen might take an
interest. In our modern world we rely on professional services to deliver time to the grid and our phones. But with all the trouble in the world, the grid might not remain reliable. People will then have to return to the historical, traditional methods of knowing time and direction from the sky. If you have any friends that fit that description, please point them to the new site. I'm considering creating some small books compiling some of the topics discussed over the last 20 years in this newsletter. I'm also thinking about ordering some Classical Astronomy t-shirts. Please let me know if you might be interested in such products. For
anyone in Northeast Ohio, I'll be giving a presentation at the Set Your Feet gathering for Charlotte Mason homeschoolers on Saturday, July 12 in Hudson, Ohio. I'm happy to support the CM community which has kept our
Signs & Seasons curriculum in print all these years. If you attend, please come over and say hi. Auroras and Other Signs in the Heavens In case you were wondering, NO, I did not see the aurora on the night of May 14. I had a family commitment that evening and the show was over over by the time I had a chance to look. While people were "oohing and ahhing" over the
pretty colors, I was concerned. This was the most powerful aurora display in a century, visible in Puerto Rico and elsewhere in the tropics down to latitude +/- 18 degrees. Thankfully it did not result in major electrical failures as some had predicted. But the Sun has not yet reached solar maximum, and such might yet still be possible. I've lately been following the Space Weather News. I used to follow this guy a dozen years ago during the last solar maximum. He has some dubious views, that solar activity might cause various sci-fi movie
scenarios to happen in real life. But he gives a great daily description of sunspot activity and the resulting coronal mass ejections (CMEs) that impact the Earth, so it's worth 3 minutes a day of my time. I'm lately dabbling with some potentially dubious views of my own. In bygone times, any and all celestial events were deemed to
be "signs and wonders in the heavens," usually taken to be omens and bad tidings. These are generally dismissed today as natural phenomena with scientific causes, even by most Christians. But what if even today the LORD can use carefully timed natural phenomena to draw our attention? The total solar eclipse in April was quickly followed by the aurora in May, and now the "Blaze Star" is expected to erupt this summer, in accordance with scientific prediction. There is
currently a comet in the solar system which might become very prominent in October. But consider all these spectacles in light of current world events. Perhaps these "cosmic coincidences" are hints and clues in the sky urging us to earnestly seek the LORD in 2024? The historic dimming of the prominent star Betelgeuse in Orion in late 2019 shortly preceded the COVID episode in 2020. For whatever reason, there was a convergence of celestial and terrestrial circumstances. So I'm just wondering about such things these days. Whatever might be transpiring on the Earth and in the sky, I hope we can all agree that now is as
good a time as any to seek the LORD. For more information about topics from Classical Astronomy discussed in this newsletter, please check out a homeschool astronomy curriculum (but popular with adult readers too!) Visit our archive of previous editions of the Classical Astronomy Update newsletters, going back to 2007. ***** The "Blaze Star" The media is lately filling up with news stories about the
so-called "Blaze Star" -- T Coronae Borealis, or T CrB for short. Check out this story and also this one. This is not the usual sort of topic for this newsletter since it is more "modern astronomy" rather than Classical Astronomy. But people have been asking about it, and it's a celestial event that might be visible in the evening sky
this summer, so here goes nothing. As I've recently learned, there is a "recurrent nova" in the constellation Corona Borealis, the Northern Crown. This is a normally invisible star that has twice before in recorded history brightened to visibility, comparable in brightness to Polaris, the North Star. The nearby
northern stars of the Big Dipper and Cassiopeia are also second magnitude. The 100 brightest stars in the sky are magnitude 2 or brighter, and you might still be able to see these stars from a light polluted city on a clear evening. As viewed from rural areas, second magnitude stars are very conspicuous. So the point is, most of us
can expect to see T CrB if/when it brightens to second magnitude. But don't be fooled by all the splashy graphics on some of these web sites and videos. It'll be within the range of visibility but don't expect it to knock your socks off. If you were not impressed with the recent total solar eclipse, you can expect to be underwhelmed by this recurrent nova. It'll be a minor spectacle for people who can appreciate this sort of thing, not much more. We always hear a lot about "supernovas," when a star explodes in a blaze of glory, but T CrB is just a regular old nova, like the novas discovered by Tycho Brahe and Johannes Kepler in centuries past. In a chapter about Corona Borealis in
his 1899 book, astronomy author Richard Hinckley Allen reported: Here appeared very suddenly... on the
12th of May, 1866, the celebrated Blaze Star, as a 2d-magnitude visible to the naked eye for only eight days.... T Coronae would also prove to be a recurrent nova. On the night of February 9, 1946... T Coronae flared up again, reaching the 3rd magnitude, and soon subsided, almost exactly as it had done some 80 years before. Anyway, 2024 is 78 years after 1946, not a full 80 years like last time around. But there was a dip in brightness in 1946 shortly before T CrB blazed forth, and the same thing happened again this year. So for this reason, today's astronomers are expecting T CrB to brighten up in the summer of 2024. Note that Allen reports second magnitude in 1866 but Burnham reports only third magnitude in 1946, less than half as bright. How bright will T CrB blaze in 2024? Will it make it up to second magnitude or only third? Or maybe not even? No one can guarantee with certainty. The skies were a lot darker in 1866 and 1946, before the advent of streetlights, so unless this appartition at least
duplicates 1866, there will likely not be much of a show in 2024. But just in case the 2024 show does deliver, you'll want to beat the rush and become familiar with this constellation now, before the nova, so that you'll be able to compare the difference when the nova does blaze forth. Corona Borealis is an interesting little half circle of stars near the
first magnitude star Arcturus, which is the second brightest star visible from the northern hemisphere. Finding Corona Borealis You can use one of those newfangled phones apps to find Corona Borealis. You're
on your own for that. Or you can do it the old fashioned way, like I had to learn way back in the stone age before the internet. Go outside about 11:00 PM, after the end of summer twilight. Look way up above toward the north to find the Big Dipper. (I hope you know that one!) Look at the "handle" of the Big Dipper, notice its curve, how it makes an arc-shape. The curve of the handle steers in the direction of Arcturus, so just "follow the arc to Arcturus."
You'll be looking straight up overhead, and it can get kind of dizzy, but if you can learn this simple trick, you will have made a great start in learning the constellations. Arcturus is the brightest star in that part
of the sky so you really can't miss it, even from the light polluted city. Once you get accustomed to identifying Arcturus, you can then learn that it is the brightest star in the constellation Boötes. Now this is NOT pronounced "boots" or "booties" as in the footwear, as in "these boots are made for walkin'." This is an ancient Greek name pronounced
"Boe-OO-tease" (three syllables) which means "herdsman." This name follows the standard rule that astro-names must be strange and complicated and counterintuitive, just to keep 21st century Americans confused. Anyway, Boötes is kind of a stetched out kite shape of third magnitude stars, like an elongated triangle with a squat triangle on top. For decades I used
to see this star pattern with no problem from my home in the city, though it's lately become a challenge since the rollout of super-bright LED streetlights. Once you can identify Boötes, just look for Corona Borealis directly to the east (i.e., the left). It's an open half-circle of stars, not much of a "crown" but more like a "tiara" of stars. Even
from the city you should have no problem spotting the brightest star, Alpha Coronae Borealis (α CrB), a fairly conspicuous second magnitude star. The other stars are more faint, and you'll need a decent rural sky to fully appreciate the star pattern of this constellation. Further to the east is Hercules, best spotted by the "keystone" asterism, a less obvious trapezoid of magnitude 2.5 stars. Far to the east is the bright first magnitude star Vega, the northwest point of the Summer
Triangle, which is rising in the evening in the current season. If you can spot Arcturus and Vega, you ought to be able to find Corona Borealis and Hercules in between. If you can become familiar with these constellations now, you'll be able to notice T CrB if reaches second magnitude brightness this summer. In that event it will be comparable in brightness
to nearby α CrB. If you succeed, then you can tell your grandchildren that you witnessed the third apparition of T CrB in 2024. For my own part, I'm skeptical of the predictions. As we saw above, the second apparition in 1946 failed to reach second magnitude, only attaining magnitude three. If this event is 4th magnitude or fainter, it'll be a nothingburger. Also, the eyewitnesses in 1866 and 1846 reported
initial peak brightness which quickly dimmed each night. If you miss it on the first night, it'll probably be a nothingbuger by the next night. I'm also wary of the timing. The professional astronomers have very little experience with this recurrent nova, none in living memory, and cannot be sure of their facts. While the nova is predicted to recur
this summer, I wouldn't surprised if it happened later, maybe the fall or winter when those stars are harder to see. In any event I'm expecting they'll have a lot to learn. So What's Up With T CrB? You might be wondering why the T
CrB nova happens in the first place? As Allen wrote in 1899: It was the first temporary star to be "studied by the universal chemical method" -- the spectroscope. Since the 19th century astronomers have studied the stars using
spectroscopy. This is the basis of modern astronomy and is totally different than Classical Astronomy. The light of a star collected by a telescope is split into its spectrum, spread out into a rainbow. It is known from chemistry that each chemical has its own set of colors unique to that chemical, and these appear as different lines of color in the spectrum of visible light, from blue to red. The spectrum of each chemical is as distinct as a fingerprint.
So when astronomers use spectroscopy, they can determine the chemical composition of a star based on the spectrum of the light emitted by that star. From such a study, astronomers determine that starlight mostly includes the chemical signatures of the elements hyrdogen and helium, with some amount of carbon and iron and other elements. In fact, the light
from helium was first detected in the spectrum of the Sun before the element was physically discovered on Earth. From determining the chemical composition of stars from starlight, astronomers then concoct a reverse-engineered naturalistic scenario of solar evolution based on the premise that nuclear fusion is occurring in the stars which created these elements.
This is the basis for astrophysics and cosmology. For my own part, I am not interested in these aspects of modern astronomy, which is why I have focused my interest on Classical Astronomy. Burnham reports the following, based on spectroscopy: The spectrum of T Coronae is peculiar and shows a dual or composite nature. There is little doubt that the star is a close double. Long story short, the "dual or composite" spectrum means that spectroscopy has detected stellar spectra associated with two stars, a red giant and a smaller, fainter blue dwarf, so that T CrB is a binary star
system. Burnham continues: ... the computed orbit places the blue star virtually in contact with the outer edges of the red giant. ... material must be passing across to go into orbit around the blue star or to fall into it. So the
storyline of T CrB is that when enough red giant material falls into the blue dwarf, after 80 years or so, a fusion reaction ignites the material so that the star blazes forth with a brightness 2500 times greater than normal. Based on Burnham's description T CrB might look something like this: This reminds me of a scenario for a Star Trek episode. The Enterprise is assigned to transport a "forehead of the week" alien scientist to T CrB to study the 80 year outburst. The Enterprise is close to the star to take careful measurements but needs to be far away from T CrB before it
blows. But something happens and there's a problem with the warp core at the last minute, and Wesley helps Geordi fix the problem just in the nick of time so that the Enterprise can get away and survive for a next episode. Be careful if you decide to google the Blaze Star. The search results will include a lot of hits for a certain notorious "burlesque
performer" who began her career shortly after the 1946 appartition. I've unsuccessfully tried to determine whether T CrB was a big media story in 1946, in case this person's stage name was inspired by the celestial event. Can't find any headlines from the period to that effect. I did find that there was a popular Christian romance story published by Eerdmans in 1939 entitled Blaze Star and it was in its sixth printing in 1946. I didn't have the time or inclination to read it to see if this story made any
reference to T CrB, of if perhaps the aforementioned person might have swiped the stage name from this book, or if it's all just a coincidence. Anyway, seems to be there are a lot of "ifs" in the scientific prognostications of T CrB for the summer of 2024. But hey, you never know. Pay close attention to T CrB each clear night over the summer and keep your eyes
peeled for any headlines. Hope you get a chance to see it. Drop me a line if you do. Till next time, God bless and clear skies, - jay The Ryan Family Cleveland, Ohio, USA When I consider thy heavens, the work of thy fingers, the moon and the stars, which thou hast ordained, what is man that thou art mindful of him? and the son of man, that thou visitest him? - Psalm 8:3-4, a Psalm of David
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