🌌 Astronomers Found the Remains of a Galaxy the Milky Way Ate 12 Billion Years Ago
The Milky Way did not grow up quietly.
Astronomers have found strong evidence that our Galaxy swallowed a substantial dwarf galaxy about 12.3 billion years ago — when the Universe was still very young. The merger happened roughly 1.8 billion years before the better-known Gaia–Sausage–Enceladus collision, previously one of the earliest major events firmly traced in the Milky Way’s history.
The clue came from globular clusters — ancient, densely packed groups of stars that preserve a kind of archaeological record of the Galaxy. Using extremely precise Hubble Space Telescope measurements, researchers identified a third distinct age-and-metallicity sequence among clusters in the inner Milky Way. That sequence points to a separate progenitor galaxy with a stellar mass of about 500 million Suns.
The team named the lost galaxy Low-energy-Kraken-Heracles, or LKH. Most of its stars appear to have been deposited within the inner 6,000 parsecs of the Milky Way, where their original identity has long since been erased by billions of years of mixing.
In other words, parts of the night sky above us may be made from the remains of another galaxy that disappeared before Earth existed.
Galaxies do not simply form. They assemble themselves by consuming one another.
#MilkyWay #Astronomy #Hubble #Galaxies #Cosmology #Science
https://www.nature.com/articles/s41550-026-02931-5
The Milky Way did not grow up quietly.
Astronomers have found strong evidence that our Galaxy swallowed a substantial dwarf galaxy about 12.3 billion years ago — when the Universe was still very young. The merger happened roughly 1.8 billion years before the better-known Gaia–Sausage–Enceladus collision, previously one of the earliest major events firmly traced in the Milky Way’s history.
The clue came from globular clusters — ancient, densely packed groups of stars that preserve a kind of archaeological record of the Galaxy. Using extremely precise Hubble Space Telescope measurements, researchers identified a third distinct age-and-metallicity sequence among clusters in the inner Milky Way. That sequence points to a separate progenitor galaxy with a stellar mass of about 500 million Suns.
The team named the lost galaxy Low-energy-Kraken-Heracles, or LKH. Most of its stars appear to have been deposited within the inner 6,000 parsecs of the Milky Way, where their original identity has long since been erased by billions of years of mixing.
In other words, parts of the night sky above us may be made from the remains of another galaxy that disappeared before Earth existed.
Galaxies do not simply form. They assemble themselves by consuming one another.
#MilkyWay #Astronomy #Hubble #Galaxies #Cosmology #Science
https://www.nature.com/articles/s41550-026-02931-5
Nature
Evidence of a massive accretion event 1.8 billion years before the Gaia-Sausage-Enceladus merger
Nature Astronomy - By studying the dynamical properties, age and metallicity of globular clusters in the inner Galaxy, the authors found evidence of a massive dwarf galaxy that was accreted by the...
👍20🔥16😁8👀2
🪐 Saturn Has Grown a Giant 10-Sided Storm Pattern
Saturn has been famous for decades for the enormous hexagon circling its north pole.
Now Hubble has discovered something even stranger at the opposite end of the planet: a vast decagon — a 10-sided atmospheric wave — surrounding Saturn’s south pole.
The structure sits roughly between 58° and 63° south latitude inside a jet stream moving at about 400 km/h. The decagon itself drifts much more slowly around the planet, at about 10 km/h, while its corners oscillate back and forth over periods of roughly a month. Multiwavelength Hubble observations show that the pattern extends through several atmospheric levels rather than existing as a superficial cloud shape.
What makes the discovery particularly intriguing is that it seems to be new. Cassini saw no comparable structure before its mission ended in 2017. Hubble data reveal faint hints beginning in 2023, with the ten-sided shape becoming increasingly distinct in 2024 and 2025. Astronomers may therefore be watching a giant planetary wave form almost in real time.
Scientists do not yet know why Saturn produces geometric atmospheric structures at all. Models suggest the decagon may be a huge wave trapped inside the jet stream, possibly triggered by an instability or a nearby vortex. But why the north settled on six sides and the south apparently chose ten remains unexplained.
Earth gets hurricanes.
Saturn apparently prefers geometry.
#Saturn #Hubble #Astronomy #PlanetaryScience #Space #Science
https://www.science.org/doi/10.1126/sciadv.aee4251
Saturn has been famous for decades for the enormous hexagon circling its north pole.
Now Hubble has discovered something even stranger at the opposite end of the planet: a vast decagon — a 10-sided atmospheric wave — surrounding Saturn’s south pole.
The structure sits roughly between 58° and 63° south latitude inside a jet stream moving at about 400 km/h. The decagon itself drifts much more slowly around the planet, at about 10 km/h, while its corners oscillate back and forth over periods of roughly a month. Multiwavelength Hubble observations show that the pattern extends through several atmospheric levels rather than existing as a superficial cloud shape.
What makes the discovery particularly intriguing is that it seems to be new. Cassini saw no comparable structure before its mission ended in 2017. Hubble data reveal faint hints beginning in 2023, with the ten-sided shape becoming increasingly distinct in 2024 and 2025. Astronomers may therefore be watching a giant planetary wave form almost in real time.
Scientists do not yet know why Saturn produces geometric atmospheric structures at all. Models suggest the decagon may be a huge wave trapped inside the jet stream, possibly triggered by an instability or a nearby vortex. But why the north settled on six sides and the south apparently chose ten remains unexplained.
Earth gets hurricanes.
Saturn apparently prefers geometry.
#Saturn #Hubble #Astronomy #PlanetaryScience #Space #Science
https://www.science.org/doi/10.1126/sciadv.aee4251
Science Advances
A decagon wave around Saturn’s south pole
Saturn has a unique long-lived, nearly stationary hexagon wave close to its north pole that is coupled to an intense eastward jet. Despite decades of observation, no similar wave has been reported so far in the southern hemisphere or elsewhere on Saturn.…
👍25😁11👀9🔥8