Welcome back to the Deep Dive. It's great to
be here. Today we're pointing our lens, our most
powerful lens, at a name that I think everyone
knows. A name that's basically synonymous with
space itself. Oh, absolutely. The Hubble Space
Telescope. Exactly. But we're not just talking
about the telescope. We're talking about the
man, Edwin Hubble. And his personal story is
just full of these incredible detours and remarkable
turns. It really is. It's a common mistake to
sort of conflate the man and the machine. But
Edwin Hubble, the man, is, well, he's arguably
the most important observational astronomer since
Galileo. That's a huge statement. Since Galileo.
I think it holds up. You have to understand,
before his work. Our own galaxy, the Milky Way,
was the entire cosmos. That was it. The whole
universe. The whole thing. After him, we suddenly
lived in this vast ocean of billions of other
galaxies. He laid the groundwork, the observational
foundation, for what we now call modern cosmology
and extragalactic astronomy. Okay, so let's unpack
that. That is a monumental legacy. Our mission
for this deep dive is to synthesize his life
and the foundational discoveries that really
made that transformation possible. We've got
our shared sources here, and they detail his,
well, highly unusual path to science, some crucial
detours during wartime, and most importantly,
two primary revolutionary scientific discoveries.
That's right. The first one is maybe the easiest
to grasp. But it's no less profound. It's the
conclusive proof that those nebulae, those fuzzy
patches in the sky. Yeah, that everyone thought
were just gas clouds. Exactly. He proved they
weren't gas clouds inside our galaxy at all.
They were entirely separate stellar systems,
other galaxies, far, far outside the Milky Way.
And the second discovery, which really launched
us into the Big Bang era, is the empirical proof
of what we now call Hubble's Law. The stunningly
simple linear relationship between a galaxy's
distance from us and its apparent speed moving
away from us this was the first real observation
that implied the expansion of the entire universe
though as we'll get into hubble himself was famously
and perhaps surprisingly skeptical of that interpretation
he was and we absolutely have to explore that
along with the complex history and you know the
controversies around who discovered what first
it's a fascinating story It seems like it's essential
because his personal history really provides
the context for his scientific rigor, doesn't
it? It absolutely does. Before Hubble became
the man who expanded the universe, he was a star
athlete and, believe it or not, a reluctant law
student. The journey to the top of Mount Wilson
and that 100 -inch telescope was anything but
a straight line. Okay, let's start there. Let's
start with the unexpected prodigy. Edwin Powell
Hubble, born 1889, Marshfield, Missouri. His
family moves to Illinois in 1900. Mm -hmm. And
when you look at his early years, high school,
college, the sources are overwhelming. He was
famous for being physically dominant, not some
kind of intellectual prodigy. Right, which is
so counterintuitive for a figure like this. What's
fascinating is that the records actually highlight
his spelling issues, which is a surprisingly
human detail for a cosmic giant. I love that.
But otherwise, he was a great student. It's just
that the public recognition, the fame, it was
all about his physical prowess. He was a phenomenon
in high school sports. And that physical discipline,
you can see how he later translated it into astronomical
dedication. And we're not just talking about,
you know, playing on a team. We're talking about
elite. truly dominant performance. Oh, absolutely.
The sources say he excelled in baseball, football,
and track and field. This wasn't a hobby. This
speaks to a kind of underlying drive and focus
that's just off the charts. You give us an example.
Well, there's this one detail that just jumps
out. At a single high school track meet in 1906,
one meet. He won seven first place finishes and
a third place. Seven firsts in one day. In one
day. Think about the sheer scale of that in all
these different disciplines, running, jumping,
throwing. It's just a hyper -focused, incredibly
driven personality. And he carried that right
into college at the University of Chicago. He
wasn't just on the basketball team. No, he was
leading it. He played multiple positions, center,
shooting guard, whatever was needed. And in 1907,
he led the university's team to their first ever
Big Ten conference title. It's just a bizarre
juxtaposition, isn't it? You have... one of the
foundational figures of 20th century science.
And at the same time, he's a Big Ten basketball
champion. It is strange, but I think that competitive
rigor, that ability to perform under pressure
and just focus on a goal, that's the same trait
we see resurface years later when he's locked
in the freezing cold dome at Mount Wilson, staring
through an eyepiece for hours. That makes sense.
The discipline to endure those long nights of
observation is probably the same kind of mental
muscle you need for high -level athletics. I
think so, yes. But okay. Despite this huge focus
on sports, his academic interests were still
pointing in the right direction. His undergraduate
studies were in mathematics, astronomy, and philosophy.
Right, so the intellectual foundation was definitely
being built. He got his Bachelor of Science in
1910. And there's another really important connection
here that often gets missed. What's that? His
exposure to truly rigorous experimental physics.
For a year during his undergrad, Hubble served
as a student laboratory assistant for Robert
Millikan. Wow. Robert Millikan, who, of course,
went on to win the Nobel Prize for his oil drop
experiment for measuring the charge of an electron.
The very same. Yeah. That experience had to have
profoundly shaped Hubble's methodology. It would
have emphasized precise measurement, empirical
evidence above all the theoretical guesswork.
It must have embedded this philosophy of show
me the data. Absolutely. He was learning from
one of the best experimentalists on the planet
how to design observations that minimized error
and maximize certainty. That training is so crucial
because later in his life, Hubble becomes the
ultimate empiricist. He trusts what he observes
through the telescope far more than what any
theorist predicts on a blackboard but then right
when he's on this path comes this huge confusing
detour the promise and the pivot his path was
just abruptly shifted by a promise he made to
his dying father right his father passed away
in 1913 and hubble feeling this deep sense of
duty followed his father's wish that he pursues
a career in law So this leads him to accept a
Rhodes Scholarship. At the Queen's College, Oxford.
And instead of focusing on physics or astronomy,
which was clearly his passion, he studies jurisprudence.
Law school in England. It seems so completely
opposed to celestial mechanics. It was a total
abandonment of his passion, at least for a time.
While he was there, he did broaden his studies.
He added literature and Spanish, eventually got
an MA degree. But the core focus was legal training.
It's just hard to imagine the man who discovered
the expanding universe arguing torts. It really
is. Though maybe that legal training, that focus
on evidence and logical argument, maybe that
subtly reinforced his scientific approach. That's
a great point. It's all about examining evidence,
building a case, and avoiding claims you can't
substantiate. That's good science and it's good
law. So when he comes back to the Midwest after
his father's death, his lack of passion for law
becomes, well, pretty obvious. His actions speak
volumes. Instead of opening a legal practice,
he takes what you might call a teaching interlude.
He ends up teaching Spanish, physics, and math
at a high school in Indiana. New Albany High
School. And, of course. And, of course, he coached
the boys' basketball team. You can't keep him
away from the court. It's just a wonderful image,
isn't it? The future titan of cosmology explaining
the quadratic formula and then diagramming a
pick -and -roll play. It is. But thankfully for
the history of science, this was a very short
-lived phase. Right. This period probably just
solidified for him how much he wanted to be doing
research. I think so. And the academic community
saw it too. A former professor from the University
of Chicago basically intervened, using Hubble's
clear talent to guide him back onto the scientific
track. And that brings us to his formal return
to astronomy. He enters graduate school at the
University of Chicago's Yerkes Observatory. And
this time, the focus is absolute. He earns his
Ph .D. in 1921. And listen to the title of his
dissertation, Photographic Investigations of
Faint Nebulae. It's prophetic. It's the exact
subject that would define his entire life's work.
His intention was already centered on figuring
out what those fuzzy patches really were. Precisely.
What was it about Yerkes Observatory that made
it the perfect place for him to start this work?
What kind of tools did they have? Yerkes was
a world -class institution established by George
Ellery Hale, a name we'll hear again. It had
groundbreaking equipment. The most famous instrument
was the 40 -inch refractor telescope, which was
enormous. But critically, he also got experience
with an innovative... 26 -inch reflector telescope.
And reflectors, which use mirrors instead of
lenses, are much better for capturing the incredibly
faint light you need for deep sky photography.
That gave him a crucial skill set. And just as
his academic path is getting back on track, it's
interrupted again by a global conflict, World
War I. Yes, he actually rushes to finish his
Ph .D. requirements so he can enlist in the U
.S. Army. He was commissioned into the 86th Division,
rises to the rank of major, which again speaks
to his leadership abilities. Absolutely. The
division was sent overseas in 1918, but the armistice
was signed soon after. So our sources say that
while some of the personnel were used as replacements
elsewhere, the 86th Division itself never actually
saw combat. So he served honorably. He got the
distinction of being a major. But his observational
career was able to begin pretty much right after
the war ended. Exactly. And there's one more
crucial detail. After the war, he actually spent
a year in the UK at Cambridge sort of reengaging
with his scientific studies before he accepted
the one offer that would change astronomy forever.
The year 1919. This is the pivot point. This
is the moment Edwin Hubble meets the instrument
that will define his legacy. The call to California.
That call came directly from George Ellery Hale,
the man who built Yerkes. Hale was now the founder
and director of the Carnegie Institution's Mount
Wilson Observatory. He recognized Hubble's talent.
He saw Hubble's rigor and his potential and offered
him a staff position. Hubble accepted, and he
stayed at Mount Wilson until he died in 1953.
And his timing was just perfect. His arrival
lined up exactly with the completion of the most
powerful observational tool in human history
up to that point. It was the perfect storm of
talent meeting opportunity. The 100 -inch or
2 .5 -meter Hooker telescope had just been completed.
And to put that in context... This was the world's
largest telescope for decades. It gathered so
much more light than any previous instrument.
It offered the resolution you needed to finally
distinguish faint individual stars inside those
distant nebulae. Without the Hooker telescope,
Hubble's work would have been impossible. They
would have just remained fuzzy patches. The 100
-inch Hooker was his work... It enabled both
of the revolutionary discoveries we're going
to talk about. But he didn't stop there. He was
always at the cutting edge. Absolutely. He was
always pushing the limits. Shortly before his
death in 1953, he became the first astronomer
to use the brand new, even bigger, 200 -inch
Hale telescope at Palomar Observatory. So there's
this incredible historical symmetry. His career
is basically defined by his use of the two most
powerful instruments built in the first half
of the 20th century. It is a perfect alignment.
Okay, let's pivot back now to another one of
those surprising detours. It really proves the
versatility of his mind. His skills were so transferable
that they became vital during the next global
conflict, World War II. This is a really remarkable
chapter. During the war... Hubble puts his astronomy
career on hold and serves as a civilian at the
U .S. Army's Aberdeen Proving Ground in Maryland.
He goes from tracking distant galaxies to...
To tracking high -velocity projectiles. He was
the chief of the external ballistics branch of
the Ballistic Research Laboratory. Ballistics,
the physics of projectiles in flight. It seems
like a world away from extragalactic astronomy.
It does, but the underlying skills of observation,
precise measurement, and calculation are identical.
That's the key connection. So what was his job?
He was directing huge amounts of research focused
on exterior ballistics. His mandate was to apply
scientific rigor to increase the effective firepower
of bombs, rockets, and other projectiles. It
required incredibly detailed high -speed observation
under very difficult conditions. And he didn't
just manage the research. He actually used his
training in optics and photography to invent
new tools for this. He was a true innovator in
the lab, just like he was on the mountaintop.
The most outstanding development that's credited
to him from this period was the high -speed clock
camera. A clock camera. That implies extremely
precise timing. Exactly, which is critical for
measuring the trajectory and speed of ordnance.
This invention was a game changer. What did it
allow them to do? It allowed researchers to precisely
study the flight characteristics of bombs and
low -velocity projectiles. By capturing their
exact movements, their rotation, their stability
in flight with extremely high time resolution,
they could gather the empirical data they needed
to redesign the ordnance for better accuracy
and performance. So he took the observational
rigor he used to measure the expansion of space.
And applied it to the expansion of military might.
The results of his studies were explicitly credited
with improving the design and effectiveness of
the nation's ordinance. It was high impact, practical
physics, a world away from the philosophical
debates of cosmology. And this work earned him
significant recognition. It did. In 1946, he
received the Legion of Merit Award for his distinguished
civilian service. It just highlights the incredible
breadth of his genius. He was capable of calculating
the size of the universe and, at the same time,
optimizing the aerodynamics of a bomb. Okay,
let's return to Mount Wilson and to the work
that truly defined him. We need to set the scene
here. Before the 1920s, the astronomical community
was in the middle of what's often called the
Great Debate. What was that about? The core of
the debate was about the size of the universe.
The established scientific view, which was championed
by figures like Harlow Shapley, was that the
entire cosmos was contained within our own Milky
Way galaxy. That was it. That was the universe.
That was the universe. And all those blurry,
fuzzy patches you could see in telescopes, the
nebulae, like Andromeda, they were believed to
be gas clouds or maybe forming star systems,
but inside our galaxy. Distant, but internal.
It's important to note, though, that the idea
of external galaxies or island universes wasn't
new. Immanuel Kant had suggested it back in 1755.
Right. But without empirical proof, it was just
philosophy. That is the crucial distinction here.
Hubble is the one who turned that philosophy
into hard observational fact. And to do that,
he needed a reliable measuring stick for cosmic
distance. And that stick was the cepheid variable
star. Exactly. Can you walk us through the genius
of using cepheids? They were discovered by Henrietta
Swan Leavitt in 1908. How do they work as a standard
candle? Cepheid variables are extraordinary.
They're a type of star that pulsates, it regularly
expands and contracts, and that causes its brightness
to oscillate, to go up and down. Leavitt's brilliant
discovery was that there is a direct lockstep
relationship between how long it takes for the
star to complete one pulsation cycle, its period,
and how bright that star truly is. its intrinsic
luminosity. So the longer the period, the brighter
the star. Exactly. So they become a standard
candle. Because as soon as you measure the period
of its pulse, which is easy to do, you know its
inherent brightness. You know how bright it's
supposed to be. Okay, so if you know how bright
the star should be, and you measure how dim it
appears from Earth, the difference is purely
a function of distance. The dimmer it is, the
farther away it must be. Precisely. It's a simple
geometric principle. The challenge was applying
it. The older telescopes just couldn't gather
enough light to resolve these individual, very
faint, sephiide stars in those distant nebulae.
The 100 -inch Hooker telescope was the first
instrument powerful enough to do it. And this
brings us to the great revelation of 1924. Hubble
is meticulously photographing Andromeda, the
Triangulum Nebula. What happens when he finally
finds and measures a septide in Andromeda? In
late 1923 and early 1924, he finally manages
to resolve individual stars and confirm a Cepheid
in what was then called the Andromeda Nebula.
He famously scrawled VAR for variable right next
to the star on his photographic plate. And then
he measured its period. The distance calculation
must have been instantly shocking. It was. When
he plugged the numbers into the period luminosity
formula, the calculated distance was staggering.
It was millions of light years away. At the time,
the entire Milky Way was thought to be maybe
a few hundred thousand light years across. This
object was far, far outside the known boundary
of our galaxy. So that single observation proved,
conclusively, that the Andromeda Nebula was not
a nebula at all. It was a separate, colossal
collection of stars. An entire galaxy outside
our own. It dismantled the existing cosmological
model overnight. The universe instantly expanded
from one single stellar system, the Milky Way,
to this vast, multi -galactic archipelago. It
is the definition of a scientific paradigm shift.
This was seismic news, and it faced strong resistance
from the old guard, didn't it? Particularly from
Harlow Shapley at Harvard. Oh, the resistance
was fierce. Shapley's model of the Milky Way
was the established view, and Hubble's finding
completely undermined it. But the empirical evidence
from Mount Wilson was just too robust to ignore.
And Hubble, interestingly, took his findings
to the public. pretty quickly. He did. His findings
for Andromeda were first published in the New
York Times on November 23rd, 1924. It ensured
immediate public awareness that the universe
had just gotten a whole lot bigger. And then
he presented the results formally to the American
Astronomical Society on January 1st, 1925. And
that cemented it. He was the man who discovered
the external galaxies. The speed at which this
discovery changed the course of science is almost
unprecedented. And beyond just proving they existed.
Hubble brought order to this new cosmic zoo.
He created a classification system. That's right,
the Hubble sequence. It's often visualized as
the tuning fork diagram. He categorized galaxies
based on how they looked, their morphology. You
had ellipticals, which were smooth and featureless,
spirals with their beautiful arms, barred spirals,
which have a central bar structure, and then
irregulars. And that classification system is
still the foundation we use today, isn't it?
It is. Despite all the refinements over the years,
it's still the fundamental taxonomy for galaxies.
He didn't just find new things. He started organizing
the cosmic map for everyone who came after him.
Okay, so once Hubble established these vast...
distances, the next crucial question was how
are these massive structures moving relative
to us? And this leads to his second monumental
discovery. The expanding universe. This stage
required synthesizing two different sets of data.
First, Hubble and his team, using the suffade
method and other techniques, painstakingly estimated
the distances to dozens of these new galaxies.
By 1929, he had distance estimates for about
24 of them. So he had the distance part of the
equation. Where did the velocity part come from?
That came from pre -existing work. The crucial
velocity data came from measurements of what's
called radial velocity, the motion along our
line of sight. Which you measure from redshift.
Exactly. And those redshift measurements were
done primarily by an astronomer named Avesto
Slipher at the Lowell Observatory. Slipher had
been observing these nebulae for years and found
that the vast majority of them were redshifted.
Meaning they were moving away from us at tremendous
speeds. At incredible speeds. Hubble relied heavily
on Slipher's work and later on measurements by
his own assistant, Milton Humison, to get the
velocity for each galaxy. So he takes his distances
and he plots them against the velocity. from
Slipher and Humason. And what did that graph
look like in 1929? The result was an elegant,
terrifyingly simple straight line, a linear relationship.
This became Hubble's law. It states that a galaxy's
recessional velocity, how fast it's moving away,
is directly proportional to how far away it is.
Right. Mathematically, it's just v equals h -naught
times dh -naught is the constant of proportionality,
the Hubble constant. And what does that simple
relationship imply about the universe as a whole?
It implies that the universe is undergoing a
uniform systematic expansion. If Galaxy B is
twice as far away as Galaxy A, it appears to
be receding at twice the speed. This only makes
sense if space itself is stretching, carrying
the galaxies along with it. So there's no center
to the expansion. Exactly. Every galaxy sees
every other galaxy receding from it. It's a profound
idea. But this brings us immediately to the calibration
problem. It's a huge issue. And it's vital for
understanding why Hubble himself was so skeptical.
It is. His initial distance estimates, while
they were flawless relative to each other, the
absolute scale was dramatically wrong. Okay,
wrong. He was off by a factor of about seven.
His calculated distances were way too small.
And what caused that error? It was later found
to be a combination of things. He was confusing
two different types of Cepheid variable stars,
which have different properties. And in some
cases, he was mistaking extremely bright gas
clouds in other galaxies for the brightest individual
stars. These mistakes basically meant his yardstick
was calibrated incorrectly. So his distance scale
was too small. What was the catastrophic consequence
of that? Well, if the distances are smaller,
it means the expansion rate has to be much faster
to get galaxies to where they are today. calculated
value for the Hubble constant, H naught, was
500 kilometers per second per megaparsec. Okay,
let's pause. A megaparsec is a million parsecs,
and a parsec is about 3 .26 light years. So that's
a unit of distance. Right. So he's saying for
every million parsecs farther away a galaxy is,
its apparent velocity increases by 500 kilometers
per second. And that number 500 created a massive
crisis, didn't it? A huge crisis, because the
Hubble constant is directly linked to the age
of the universe. If you run the clock backwards,
a value of 500 gives you an estimated age for
the cosmos of only about 2 billion years. Which
was the problem. It was a catastrophic problem.
By the 1930s, geologists using radiometric dating
had already established that rocks on Earth were
older than 3 billion years old. So Hubble's own
data, taken at face value, forced this logical
obsession. The universe appeared to be younger
than the planets inside it. Precisely. And that
massive contradiction is the empirical foundation
for his famous skepticism. His dedication to
observation meant he could not accept a conclusion
that contradicted known facts about the age of
our own planet. This is what fueled his caution
for decades. And this story is further complicated
by the Lemaitre priority issue. George Lemaitre
had theoretically predicted this exact relationship
before Hubble published it. He did. Lemaitre,
a Belgian physicist and a Catholic priest, published
the theoretical prediction for an expanding universe
in 1927 in French, using Einstein's equations
of general relativity. He even included some
initial observational data to support it. That
was two full years before Hubble's famous 1929
paper. So historically, Lemaitre has both conceptual
and chronological priority. This all ties into
Hubble's own reluctance to even interpret his
data as true expansion. Right. He was the ultimate
empiricist, always wary of theoretical speculation.
He deliberately used the term apparent velocities
to describe the recession of the galaxies. So
not real velocities. He was being cautious. He
wrote in his correspondence that the interpretation
of this correlation should be left to the very
few others who are competent to discuss the matter
with authority, meaning the theorists like Einstein
and de Sitter. He thought of an observational
correlation, not necessarily proof that the fabric
of space was expanding. So what is the modern
view? Is it a Doppler shift or something else?
That's a crucial distinction. A traditional Douglas
shift is when an object moves through space.
But what we see with distant galaxies, the cosmological
redshift, is now interpreted as an increase in
the proper distance between them because the
fabric of space -time itself is expanding. Can
you give us an analogy? The classic one is raisin
bread dough rising in an oven. The raisins are
the galaxies and they're fixed in the dough,
which is space. As the dough expands, all the
raisins move farther apart from each other, but
they aren't actually moving through the dough.
I see. So the light traveling from one raisin
to another gets stretched as the dough expands.
Exactly. The light waves are stretched, making
them redder. That's cosmological redshift. It's
different from a Doppler shift, but for nearby
galaxies, the math works out to be almost the
same, which is why it's easy to confuse them.
But Hubble's caution was justified because his
observations alone couldn't prove one over the
other. And he held on to this skepticism for
his whole career. He kept questioning the Big
Bang interpretation. He did. Until the end of
his career, he maintained that a model where
no true expansion exists was still a viable possibility.
He was driven by observations that suggested
a uniform distribution of galaxies, which he
felt didn't quite fit the sudden explosion idea
implied by that early high value of his constant.
This story is just so tied up with Albert Einstein's
own intellectual journey. Let's talk about what
Einstein later called his biggest blunder. Yes,
this just highlights the incredible power of
observation to overturn even the most deeply
held theoretical beliefs. Around 1917, Einstein
had completed general relativity and his equations,
when applied to the universe as a whole, suggested
that the cosmos had to be dynamic. It should
be either expanding or contracting. But Einstein.
Like pretty much every scientist of his era had
this philosophical preference for a static, eternal
universe. He did. And to force his equations
to produce a static model, he introduced a term
he called the cosmological constant. It was basically
a mathematical fudge factor he invented to create
a repulsive force that would perfectly balance
gravity and hold the universe still. So the greatest
theorist of the age introduces this mathematical
trick to preserve a static universe. Only to
have the greatest observer of the age, Hubble,
come along and prove that the universe was decidedly
not static. It's the ultimate irony. And when
Einstein learned of Hubble's work? He realized
his theoretical bias had blinded him. He saw
the data, Slipper's redshifts and Hubble's plot,
and understood that the expansion was real. And
they actually met, right? They did. Einstein
visited Mount Wilson Observatory in 1931. He
met with Hubble. He saw the telescope. He talked
with the observational team. And after that visit,
he famously and publicly retracted the cosmological
constant, later calling it the biggest blunder
of my life. He accepted the expansion based on
the evidence. Which creates this second layer
of irony. As Einstein is finally accepting the
expansion based on Hubble's data, Hubble himself
is still internally questioning what that data
really means. It's incredible, isn't it? Hubble
remains skeptical. He was so troubled by that
age discrepancy and the uniform distribution
of galaxies. In a 1941 report based on a six
-year survey, he explicitly argued that his results
did not support the pure expanding universe theory.
He said the uniformity didn't fit the explosion
idea. It shows this deep intellectual split.
Hubble is saying, my telescope shows me a universe
that looks uniform, and my numbers say the universe
is younger than the Earth, so I have to question
the expansion interpretation. it's a powerful
lesson in scientific humility he refused to let
theory dictate his observations he held open
the possibility that redshift was caused by in
his words a hitherto unrecognized principle of
nature like the tired light theory exactly the
idea that light simply loses energy as it travels
vast distances that's been ruled out now but
his willingness to challenge the prevailing view
based on conflicting data is what made him such
a great scientist okay let's Let's address the
most serious historical controversy, the LeMetre
redaction issue. For many years, this cast a
real shadow on Hubble's legacy. It did. For decades,
there was this deep suspicion surrounding the
English translation of George LeMetre's 1927
paper. The original French paper included observational
evidence supporting the expansion law, including
his own calculated value for the expansion rate.
But when the English translation was published
in 1931, Those key paragraphs were missing. They
were gone. And the immediate damning conclusion
that many people drew was that Hubble, or someone
close to him, must have redacted those sections
to make sure he kept priority for Hubble's law,
which he published in 1929. It seemed plausible,
an attempt to rewrite scientific history in his
favor. It did, because Lemaitre clearly had theoretical
and arguably observational priority from 1927.
If the content was suppressed, it would have
been a major ethical breach. So how is this finally
resolved? The resolution came in 2011, thanks
to the astronomer Mario Lubio. He did some historical
detective work and found a letter in the LaMetra
archive that provided the definitive answer.
And the person who requested the redaction was?
LaMetra himself. Why on earth would he remove
his own foundational data from the English translation?
It was an act of humility and practicality. Lemaître
felt that his specific observational data from
1927 had already been superseded by Hubble's
more extensive and robust data from 1929. He
saw no reason to reproduce what he considered
obsolete data in the 1931 translation, which
he wanted to focus on the theoretical implications.
So the letter completely cleared Hubble of that
charge, although the fact of Lemaître's chronological
priority is still undisputed. Moving on to another
professional struggle. Hubble spent much of his
later career chasing an honor that ultimately
slipped through his fingers. The Nobel Prize.
This was a determined campaign. At the time,
the Nobel Committee didn't consider astronomy
to be part of physics. They saw it more as a
descriptive observational science. And Hubble
argued against that. Vigorously. He and his colleagues
argued that foundational work like... Proving
the existence of other galaxies and charting
the expansion of the universe was clearly fundamental
physics. It was cosmology. The physics of the
universe. Exactly. He lobbied tirelessly, writing
letters, trying to change the rules. And the
heartbreaking twist is that he succeeded, but
too late. The timing is just tragic. The Nobel
Committee eventually did decide that astronomical
work would be eligible for the physics prize.
But that ruling was enacted shortly after Hubble
died in September 1953. And since the Nobel Prize
cannot be awarded posthumously, he missed out
on the recognition he had campaigned for and
so fundamentally deserved. He broke the universe
open for us, only to be deemed ineligible for
the prize that celebrates exactly those kinds
of breakthroughs. A truly poignant end to that
part of his story. Despite the controversies
and the missed Nobel. Hubble's publications made
sure his methods and discoveries were codified
for future generations. Oh, yes. His foundational
books are still cornerstones of cosmology. You
look at The Realm of the Nebulae from 1936 and
The Observational Approach to Cosmology from
1937. These books didn't just report his data.
They laid out his entire empirical philosophy
and standardized the way we classify galaxies.
They laid the groundwork for everything that
followed. And on a personal level, he married
Grace Lillian Burke in 1920. just a few months
before his monumental Andromeda discovery. Grace
was central to his life. She managed his social
profile and later was the fierce guardian of
his intellectual legacy. We know his health began
to decline in the late 1940s. He had a heart
attack in 1949. He continued to work on a restricted
schedule, but his health was precarious. He died
from a blood clot in the brain, a cerebral thrombosis,
on September 28, 1953. And this brings us to
one of the most intriguing and mysterious final
details of his life. A secret his wife kept until
her own death decades later. Yes, the final mystery
of Edwin Hubble. There was no public funeral
service held for him. An even stranger, his wife,
Grace, never revealed where he was buried. So
no one knows. No one knows. She donated all his
papers, his logbooks, his correspondence. But
the location of his final resting place remains
a complete mystery to this day. It's an almost
mythical ending for a man who charted the boundaries
of the cosmos. His own final location is one
of the universe's small secrets. It is. But despite
that personal secrecy, his professional legacy
is spectacularly public. It's marked by so many
enduring honors. The most famous, of course,
is the Hubble Space Telescope. An instrument
that continues his work, pushing the limits of
observation far beyond what he could have ever
dreamed of with the 100 -inch Hooker Telescope.
But his name is also stamped all over the place.
Asteroid 2069 Hubble, the Hubble Crater on the
Moon, the Edwin Hubble Highway in Missouri. And
his lifetime awards, including the ones for his
wartime service, really highlight what a polymath
he was. The Newcomb Cleveland Prize, the Bruce
Medal, the Franklin Medal, the Gold Medal of
the Royal Astronomical Society, and of course
the Legion of Merit for his ballistics research.
A stunning list of accomplishments. His story
is now permanently woven into our popular understanding
of science, perhaps most famously through Carl
Sagan. Sagan made sure Hubble's legacy reached
a massive audience. He featured him prominently
in his 1980 documentary, Cosmos, in the episode
about cosmic scale and time. He's truly crossed
over from being a scientific giant to a cultural
icon. So as we wrap up this deep dive, let's
just reflect on the monumental scale of his impact.
Hubble took humanity from thinking we lived on
a single contained stellar island to realizing
we inhabit one galaxy among billions all rushing
apart from each other in an expanding universe.
His career is really a testament to the power
of meticulous observation over even the strongest
theoretical beliefs. He said it best himself.
He wrote. We do not know why we are born into
the world, but we can try to find out what sort
of a world it is, at least in its physical aspects.
And that dedication to observation, to exhausting
the empirical resources first, led him to conclude.
Not until the empirical resources are exhausted
need we pass on to the dreamy realms of speculation.
And that, I think, perfectly frames our final
thought for you, the listener. We've established
that Hubble, the man who provided the data, remains
skeptical of the expansion of the universe until
the end. He preferred the idea that redshift
might be a sign of some hitherto unrecognized
principle of nature. Like tired light. Today,
physics is far more confident in the metric expansion
model. So our question is this. What are the
modern empirical resources that conclusively
prove the universe is truly expanding, eliminating
all possibility for Hubble's original skepticism?
What observations, things like the light curves
of Type Ia supernovae at extreme distances, or
the tiny temperature fluctuations in the cosmic
microwave background, what observations provide
that final, zero -room -for -doubt evidence that
Hubble, the ultimate observer, would have required
to finally change his mind? That is something
worth exploring.