There Should be a few Supernovae in the Milky Way Every Century, but we’ve Only Seen 5 in the Last 1000 Years. Why?

This image of the supernova remnant SN 1987A was taken by the NASA/ESA Hubble Space Telescope in January 2017 using its Wide Field Camera 3 (WFC3). Since its launch in 1990 Hubble has observed the expanding dust cloud of SN 1987A several times has helped astronomers get a better understanding of these cosmic explosions. Supernova 1987A is located in the centre of the image amidst a backdrop of stars. The bright ring around the central region of the exploded star is material ejected by the star about 20 000 years before the actual explosion took place. The supernova is surrounded by gaseous clouds. The clouds’ red colour represents the glow of hydrogen gas. Image Credit: NASA, ESA, and R. Kirshner (Harvard-Smithsonian Center for Astrophysics and Gordon and Betty Moore Foundation) and P. Challis (Harvard-Smithsonian Center for Astrophysics)

Our galaxy hosts supernovae explosions a few times every century, and yet it’s been hundreds of years since the last observable one. New research explains why: it’s a combination of dust, distance, and dumb luck.

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Past Supernovae Could be Written Into Tree Rings

When stars reach the end of their lifespan, they undergo gravitational collapse at their cores. The type of explosion that results is one of the most awesome astronomical events imaginable and (on rare occasions) can even be seen with the naked eye. The last time this occurred was in 1604 when a Type Ia supernova took place over 20,000 light-years away – commonly-known as Kepler’s Supernova (aka. SN1604)

Given the massive amounts of radiation they release, past supernovae are believed to have played a role in the evolution of our planet and terrestrial life. According to new research by CU Boulder geoscientist Robert Brakenridge, these same supernovae may have left traces in our planet’s biology and geology. These findings could have implications given fears that Betelgeuse might be on the verge of going supernova.

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Astronomers Map Out the Raw Material for New Star Formation in the Milky Way

A team of researchers has discovered a complex network of filamentary structures in the Milky Way. The structures are made of atomic hydrogen gas. And we all know that stars are made mostly of hydrogen gas.

Not only is all that hydrogen potential future star-stuff, the team found that its filamentary structure is also a historical imprint of some of the goings-on in the Milky Way.

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Supercomputer Simulation Shows a Supernova 300 Days After it Explodes

The answers to many questions in astronomy are hidden behind the veil of deep time. One of those questions is around the role that supernovae played in the early Universe. It was the job of early supernovae to forge the heavier elements that were not forged in the Big Bang. How did that process play out? How did those early stellar explosions play out?

A trio of researchers turned to a supercomputer simulation to find some answers.

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A Star had a Partial Supernova and Kicked Itself Into a High-Speed Journey Across the Milky Way

Supernovae are some of the most powerful events in the Universe. They’re extremely energetic, luminous explosions that can light up the sky. Astrophysicists have a pretty good idea how they work, and they’ve organized supernovae into two broad categories: they’re the end state for massive stars that explode near the end of their lives, or they’re white dwarfs that draw gas from a companion which triggers runaway fusion.

Now there might be a third type.

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Detecting the Neutrinos From a Supernova That’s About to Explode

Neutrinos are puzzling things. They’re tiny particles, almost massless, with no electrical charge. They’re notoriously difficult to detect, too, and scientists have gone to great lengths to detect them. The IceCube Neutrino Observatory, for instance, tries to detect neutrinos with strings of detectors buried down to a depth of 2450 meters (8000 ft.) in the dark Antarctic ice.

How’s that for commitment.

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Astronomers Might Have Seen a Star Just Disappear. Turning Straight to a Black Hole Without a Supernova

Large stars have violent deaths. As they run out of hydrogen to fuse, the star’s weight squeezes its core to make it increasingly hot and dense. The star fuses heavier elements in a last-ditch effort to keep from collapsing. Carbon to Silicon to Iron, each step generating heat and pressure. But soon it’s not enough. The fusion even heavier elements don’t give the star more energy, and the core quickly collapses. The protons and neutrons of nuclei collide so violently that the resulting shock wave rips the star about. The outer layers of the star are thrown outward, becoming a brilliant supernova. For a brief time, the star shines brighter than its entire galaxy, and its core collapses into a neutron star or black hole. It was thought that all large stars end with a supernova, but new research finds that might not be the case.

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Much of the Lithium Here on Earth Came from Exploding White Dwarf Stars

The Big Bang produced the Universe’s hydrogen, helium, and a little lithium. Since then, it’s been up to stars (for the most part) to forge the rest of the elements, including the matter that you and I are made of. Stars are the nuclear forges responsible for creating most of the elements. But when it comes to lithium, there’s some uncertainty.

A new study shows where much of the lithium in our Solar System and our galaxy comes from: a type of stellar explosion called classical novae.

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A New Kind of Supernova Explosion has been Discovered: Fast Blue Optical Transients

For the child inside all of us space-enthusiasts, there might be nothing better than discovering a new type of explosion. (Except maybe bigger rockets.) And it looks like that’s what’s happened. Three objects discovered separately—one in 2016 and two in 2018—add up to a new type of supernova that astronomers are calling Fast Blue Optical Transients (FBOT).

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Take a Peek Inside a Giant Star Right Before it Dies

The biggest stars in our universe are some of the most fascinatingly complex objects to inhabit the cosmos. Indeed,giant stars have defied full explanation for decades. Especially when they’re near the end of their lives.

Stars power themselves through nuclear fusion, from the smashing together of lighter elements into heavier ones. This process leaves behind a little bit of extra energy. It’s not much, but when those fusion reactions occur at millions or billions of times every single second, it’s enough to keep a star powered for…millions or billions of years.

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