How Edwin Hubble Expanded the Universe 100 Years Ago (wikipedia.org) 26
Black Parrot (Slashdot reader #19,622) pointed out a historic anniversary this week:
On October 6, 1923, Edwin Hubble got a photo of Andromeda that showed that it contained a variable star, and therefore was an actual galaxy, ending the Great Debate over whether the universe consisted of anything beyond our own galaxy.
Unless you're more than 100 years old you grew up with a completely different understanding of the universe than anyone who lived before. Even Einstein did not know about it when he proposed the theory of general relativity.
It was later in the decade before Hubble discovered that the universe is expanding.
A century later, the European Space Agency was announcing... A very rare, strange burst of extraordinarily bright light in the universe just got even stranger â" thanks to the eagle-eye of the NASA/ESA Hubble Space Telescope. The phenomenon, called a Luminous Fast Blue Optical Transient (LFBOT), flashed onto the scene where it wasnâ(TM)t expected to be found, far away from any host galaxy. Only Hubble could pinpoint its location. The Hubble results suggest astronomers know even less about these objects than previously thought by ruling out some possible theories.
Bill Kendrick (Slashdot reader #19,287) writes: Edwin Hubble's discovery — thanks to a Cepheid Variable star — that the "Andromeda Nebula" was actually an entire galaxy 2.5 million light years away... NASA's Astronomy Photo of the Day for today celebrates this with an image of the original photo plate from October 6, 1923. Notice the "N" (for nova) crossed off, and "VAR!" (for variable) next to the star!
The discovery of Cepheids, and the important fact that their brightening and dimming was regular, and could be used to determine a star's intrinsic brightness, was thanks to Henrietta Swan Leavitt about a decade earlier.
David Butler's "How Far Away Is It?" series has an excellent episode on Andromeda on YouTube.
Unless you're more than 100 years old you grew up with a completely different understanding of the universe than anyone who lived before. Even Einstein did not know about it when he proposed the theory of general relativity.
It was later in the decade before Hubble discovered that the universe is expanding.
A century later, the European Space Agency was announcing... A very rare, strange burst of extraordinarily bright light in the universe just got even stranger â" thanks to the eagle-eye of the NASA/ESA Hubble Space Telescope. The phenomenon, called a Luminous Fast Blue Optical Transient (LFBOT), flashed onto the scene where it wasnâ(TM)t expected to be found, far away from any host galaxy. Only Hubble could pinpoint its location. The Hubble results suggest astronomers know even less about these objects than previously thought by ruling out some possible theories.
Bill Kendrick (Slashdot reader #19,287) writes: Edwin Hubble's discovery — thanks to a Cepheid Variable star — that the "Andromeda Nebula" was actually an entire galaxy 2.5 million light years away... NASA's Astronomy Photo of the Day for today celebrates this with an image of the original photo plate from October 6, 1923. Notice the "N" (for nova) crossed off, and "VAR!" (for variable) next to the star!
The discovery of Cepheids, and the important fact that their brightening and dimming was regular, and could be used to determine a star's intrinsic brightness, was thanks to Henrietta Swan Leavitt about a decade earlier.
David Butler's "How Far Away Is It?" series has an excellent episode on Andromeda on YouTube.
We rented the 100" scope for the night (Score:5, Interesting)
Re: (Score:3)
Re: (Score:2)
I used to buy used textbooks at garage sales when I was a kid in the '60s when I ran out of things to read, I remember the astronomy textbook (don't remember the copyright date on it) discussing the recently discovered "island universes", as galaxies were called.
Re: (Score:2)
We are kind of blessed in this day and age that you can get portable cassegrains with motorized tripods you can control with a laptop all for under $1k with change, that will , with a bit of patience, give you photographs that will run rings around the kind of things people where looking at with these 100" monsters back in the day.
Its a *fascinating* hobby, though rather frusturating (clouds, weather, city lights, silicon valley techbro fools spamming the sky with sattelites etc)
VAR? (Score:3)
I'm presuming that big black thing in the middle of the plate is the Andromeda galaxy and to which Hubble was referring to when he wroter VAR! I'm only saying that because normally when something like this is recorded, people will put their note directly next to the item in question, use an arrow to point to it, or even use the proverbial red circle to identify what they mean, like so [livescience.com].
Re:VAR? (Score:5, Informative)
I'm presuming that big black thing in the middle of the plate is the Andromeda galaxy and to which Hubble was referring to when he wroter VAR! I'm only saying that because normally when something like this is recorded, people will put their note directly next to the item in question, use an arrow to point to it, or even use the proverbial red circle to identify what they mean, like so [livescience.com].
The image is a negative, so everything that's black here is actually white in the sky. The black smudge is the core of the Andromeda galaxy, but what Hubble was looking at was the stars in the outskirts. Three of these he saw were new on this plate, and he labeled them "N" for "Nova". One of them he later realized wasn't a nova but was a variable star, so he crossed off the "N" and wrote "VAR". It's the tiny tiny black dot, with the two lines on either side to make it clear which black dot.
This site has more (and shows the image as a positive, not a negative (even though Hubble worked with the negatives, as did pretty much all astronomers back then): https://esahubble.org/images/o... [esahubble.org]
Re: (Score:2)
I realize it's a negative, but I was thinking that large black spot was the Andromeda galaxy itself and everything else were just stars somewhere else in the universe. Your comment clears up that point.
The second also makes sense. That was my original thought, those two lines pointing the star in question, but then thought it was something else he wrote for some reason.
Thanks for the answer and clearing things up.
Hubble's assistant ... (Score:5, Interesting)
In my early readings about Edwin Hubble, the name Milton Humason appeared sparsely. The mentions alerted me to a possible story and, boy did I find out!
Milton L. Humason helped carry observatory parts up the mountain to the Mount Wilson Observatory, he was working as a mule driver. This was his initial job at the observatory before he transitioned into a role as a night assistant, which eventually led to his significant contributions to the field of astrophysics through his collaboration with Edwin Hubble.
In 1935, Humason was elected as an honorary member of the Royal Astronomical Society in the United Kingdom, a prestigious honor in the field of astronomy.
Here's the book. [amazon.com]
Re: (Score:2)
Re: (Score:2)
Led by Humason. It's an amazing story.
Re: (Score:3)
From what I understand, even nowadays a lot of material is still hauled into Los Angeles by mule [wikipedia.org].
Re: (Score:2)
Don't know if it's in the book, but apparently he was also the go-to guy at the observatory if you wanted "moonshine."
Re: (Score:2)
There may be something about that in the book.
There is a story associated with Milton L. Humason providing "moonshine" (illegally distilled alcohol) to workers at the Mount Wilson Observatory during the Prohibition era in the United States. It is said that Humason and some of his colleagues occasionally made and consumed homemade alcohol on the premises, as Prohibition (which lasted from 1920 to 1933) had banned the production and sale of alcoholic beverages in the country.
Re: (Score:2)
That quote is from ChatGPT. I checked with Claude as well.
Re: (Score:2)
This was on an episode of the (original Carl Sagan) Cosmos.
Re: (Score:2)
There was a nice segment featuring Humason in the original 'Cosmos'.
Re: (Score:1)
Are 80-90 year old papers the best you can come up with? What did the Babylonians have to say about it?
Re: (Score:2)
Hubble discovered the expansion of the universe, just as Columbus discovered the Americas. It doesn't matter if Hubble didn't believe his evidence or that Columbus insisted to his dying day that he'd gone to Asia. They found the proof.
Take a tour if you can. (Score:2)