Origin stories are a focus of many astronomical studies. Planetary formation, solar system formation, and even galaxy formation have long been studied in order to understand how the universe came to be where it is today. Now, a team of scientists from the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) consortium have found an extremely early “protogalaxy” that was formed approximately 750 million years after the big bang. Studying it can provide insights into that early type of galaxy formation and everything that comes after.Continue reading “Protogalaxy Cluster Found When the Cosmic Fog Was Starting to Clear, When the Universe Was Just 750 Million Years Old”
A galaxy’s main business is star formation. And when they’re young, like youth everywhere, they keep themselves busy with it. But galaxies age, evolve, and experience a slow-down in their rate of star formation. Eventually, galaxies cease forming new stars altogether, and astronomers call that quenching. They’ve been studying quenching for decades, yet much about it remains a mystery.
A new study based on the IllustrisTNG simulations has found a link between a galaxy’s quenching and its stellar size.Continue reading “Astronomers Can Predict When a Galaxy’s Star Formation Ends Based on the Shape and Size of its Disk”
What happens when galaxies collide? Well, if any humans are around in about a billion years, they might find out. That’s when our Milky Way galaxy is scheduled to collide with our neighbour the Andromeda galaxy. That event will be an epic, titanic, collision. The supermassive black holes at the center of both galaxies will feast on new material and flare brightly as the collision brings more gas and dust within reach of their overwhelming gravitational pull. Where massive giant stars collide with each other, lighting up the skies and spraying deadly radiation everywhere. Right?
Maybe not. In fact, there might be no feasting at all, and hardly anything titanic about it.Continue reading “When Galaxies Collide, Black Holes Don’t Always Get the Feast They Were Hoping for”
Galaxy mergers are beautiful sights, but ultimately deadly. In the midst of the collision, the combined galaxy will shine brighter than it ever has before. But that glory comes with a price: all those new stars use up all the available fuel, and star formation grinds to a halt.Continue reading “Galaxy Mergers can Boost Star Formation, and it can Also Shut it Down”
Computers are known for their ability to spot patterns. It’s what they are good at, and over the last 50+ years they have continued to improve. But they only know how to spot patterns if they know where to look for them in data. So sometimes, it falls to a human to truly see a pattern that no one expected to be there.
That is exactly what happened in the case of the discovery of the most consistent active galaxy yet discovered. Anna Payne, a graduate student at the University of Hawai’i at Manoa, was looking into data collected by the All Sky Automated Survey for Supernovae (ASAS-SN), and notice a strange feature about one of its galaxies, known as ESO 253-3: it was getting significantly brighter every 114 days.Continue reading “An Active Galaxy That Erupts Predictably Every 114 Days Or So”
Audio narration by the author is available above
10 billion years ago, galaxies of the Universe were ablaze with the light of newly forming stars. This epic phase of history is known as “Cosmic Noon” – the height of all star creation. Galaxies like our Milky Way aren’t creating stars at nearly the rates they were in the ancient past. However, there is a time when galaxies in the present can explode with star formation – when they collide with each other. This recently published collage of merging galaxies by the Hubble HiPEEC survey (Hubble imaging Probe of Extreme Environments and Clusters) highlights six of these collisions which help us understand star formation in the early Universe.Continue reading “The Universe in Formation. Hubble Sees 6 Examples of Merging Galaxies”
Say hello to NGC 6946, otherwise known as the Fireworks Galaxy. This little galaxy is the most prolific producer of supernovae in the known universe, popping off those incredible explosions roughly once a decade. It’s secret? An incredibly high rate of star formation.Continue reading “This is the Fireworks Galaxy. It’s had ten Supernovae in the Last Century Alone”
Galaxies are supposed to build up a very slowly, taking billions of years to acquire their vast bulk. But a newfound galaxy, appearing in the universe when it was only 1.8 billion years old, tells a different tale. It formed stars at a rate hundreds of times greater than the Milky Way, and was able to build itself up to host 200 billion stars in less than 500 million years – perhaps the universe’s greatest speed run.Continue reading “This galaxy took only 500 million years to form”
A monster lurks at the heart of many galaxies – even our own Milky Way. This monster possesses the mass of millions or billions of Suns. Immense gravity shrouds it within a dark cocoon of space and time – a supermassive black hole. But while hidden in darkness and difficult to observe, black holes can also shine brighter than an entire galaxy. When feeding, these sleeping monsters awaken transforming into a quasar – one of the Universe’s most luminous objects. The energy a quasar radiates into space is so powerful, it can interfere with star formation for thousands of light years across their host galaxies. But one galaxy appears to be winning a struggle against its awoken blazing monster and in a recent paper published in the Astrophysical Journal, astronomers are trying to determine how this galaxy survives.Continue reading “A Galaxy is Making New Stars Faster Than its Black Hole Can Starve Them for Fuel”
Galaxies build themselves up slowly over time by cannibalizing their neighbors. Using an advanced suite of computer simulations, researchers have now traced back the evolutionary history of our own Milky Way.Continue reading “The family tree of the Milky Way. The mergers that gave us the galaxy we see today”