About this episode
On October 5th, 1923, Edwin Hubble made a groundbreaking discovery that forever changed our understanding of the universe. While observing the night sky through the 100-inch Hooker Telescope at the Mount Wilson Observatory in California, Hubble identified a Cepheid variable star within the Andromeda Nebula (now known as the Andromeda Galaxy).
Cepheid variable stars are a special type of star that pulsates with a regular period, and their brightness is directly related to their pulsation period. This relationship allows astronomers to calculate the distance to these stars with great accuracy. Hubble's discovery of a Cepheid variable in the Andromeda Nebula allowed him to determine that it was located far beyond the boundaries of our Milky Way galaxy, which was a revolutionary idea at the time.
This revelation shattered the long-held belief that the Milky Way encompassed the entire universe. Hubble's finding provided the first concrete evidence that the universe extended far beyond our own galaxy and that countless other galaxies existed in the vast expanse of space.
Hubble's discovery opened the door to a new era of cosmology and extragalactic astronomy. It laid the foundation for future discoveries, such as the expansion of the universe and the Big Bang theory. Today, astronomers continue to build upon Hubble's work, exploring the depths of the universe and unraveling its mysteries.
So, the next time you look up at the night sky and spot the faint, fuzzy patch of the Andromeda Galaxy, remember the incredible discovery made by Edwin Hubble on this day in 1923. It's a testament to the power of human curiosity and the wonders that await us in the cosmos.
This content was created in partnership and with the help of Artificial Intelligence AI
This episode includes AI-generated content.
Cepheid variable stars are a special type of star that pulsates with a regular period, and their brightness is directly related to their pulsation period. This relationship allows astronomers to calculate the distance to these stars with great accuracy. Hubble's discovery of a Cepheid variable in the Andromeda Nebula allowed him to determine that it was located far beyond the boundaries of our Milky Way galaxy, which was a revolutionary idea at the time.
This revelation shattered the long-held belief that the Milky Way encompassed the entire universe. Hubble's finding provided the first concrete evidence that the universe extended far beyond our own galaxy and that countless other galaxies existed in the vast expanse of space.
Hubble's discovery opened the door to a new era of cosmology and extragalactic astronomy. It laid the foundation for future discoveries, such as the expansion of the universe and the Big Bang theory. Today, astronomers continue to build upon Hubble's work, exploring the depths of the universe and unraveling its mysteries.
So, the next time you look up at the night sky and spot the faint, fuzzy patch of the Andromeda Galaxy, remember the incredible discovery made by Edwin Hubble on this day in 1923. It's a testament to the power of human curiosity and the wonders that await us in the cosmos.
This content was created in partnership and with the help of Artificial Intelligence AI
This episode includes AI-generated content.
Get every episode summarized
Each time Astronomy Tonight publishes, we email you a written briefing from the transcript — the topics, who appeared, and any specific claims, with the ad reads skipped.
Email me new episodesFree for 3 shows. No card needed.
No transcript yet
This episode has not been transcribed. Request it and it moves to the front of the queue.
More episodes
More from Astronomy Tonight
# Venus Transit of 1882: Measuring the Solar System
Astronomy Tonight
Mar 24, 20261:40failed
# Arthur Auwers: The Meticulous Star Mapper Who Built Celestial GPS
Astronomy Tonight
Mar 23, 20261:40completed
Hubble's Flawed Vision: From Disaster to Discovery
Astronomy Tonight
Mar 22, 20261:41failed
# The Great Daylight Comet of 1960: A Celestial Surprise
Astronomy Tonight
Mar 21, 20261:36completed