What caused the extinction of dinosaurs?

The most recent mass extinction, wiping out dinosaurs, was likely triggered by an asteroid impact forming Chicxulub crater.

What is the Galactic Habitable Zone?

The Galactic Habitable Zone concept explores safe and unsafe areas in the galaxy, beyond the habitable zone around stars.

Gamma ray bursts can strip away the ozone layer, causing significant damage to surface life, even from a distance of 6,500 light years.

The Galactic Habitable Zone's validity is debated due to speculative arguments and lack of quantifiable data.

Supernovae are considered a primary threat to life, with varying rates across different galaxy regions.

The fossil record indicates five major mass extinctions caused by global catastrophes, with the most recent wiping out dinosaurs likely due to an asteroid impact at Chicxulub crater.
The Galactic Habitable Zone theory proposes safe and dangerous areas in the galaxy, with debates surrounding the impact of supernovae, gamma ray bursts, and metallicity on the potential for life, emphasizing the need for more concrete evidence before widely accepting this concept.

What caused the extinction of dinosaurs?
The most recent mass extinction, wiping out dinosaurs, was likely triggered by an asteroid impact forming Chicxulub crater.
What is the Galactic Habitable Zone?
The Galactic Habitable Zone concept explores safe and unsafe areas in the galaxy, beyond the habitable zone around stars.
How do gamma ray bursts affect life?
Gamma ray bursts can strip away the ozone layer, causing significant damage to surface life, even from a distance of 6,500 light years.
What is the controversy surrounding the Galactic Habitable Zone theory?
The Galactic Habitable Zone's validity is debated due to speculative arguments and lack of quantifiable data.
How do supernovae impact the Galactic Habitable Zone?
Supernovae are considered a primary threat to life, with varying rates across different galaxy regions.

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The fossil record shows five major mass extinctions over 500 million years, with global catastrophes causing significant species loss.
The most recent mass extinction, wiping out dinosaurs, was likely triggered by an asteroid impact forming Chicxulub crater.
Scientists propose astronomical threats explaining past extinctions, suggesting parts of the galaxy may be inhospitable to life.
The Galactic Habitable Zone concept explores safe and unsafe areas in the galaxy, beyond the habitable zone around stars.
The Galactic Habitable Zone theory is controversial, focusing on extinction-level threats like supernovae.
Supernovae are considered a primary threat to life, with varying rates across different galaxy regions.
The Galactic Habitable Zone's validity is debated due to speculative arguments and lack of quantifiable data.
Gamma ray bursts, a million times more powerful than supernovae, pose a significant threat to life, explaining past extinctions.
Short and long gamma ray bursts are associated with different cosmic events, with the latter being more dangerous.
Gamma ray bursts can strip away the ozone layer, causing significant damage to surface life, even from a distance of 6,500 light years.

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Galactic core in Milky Way is initially hazardous but diminishes due to metallicity, fewer metals lead to more gamma ray bursts.
High metallicity stars may shed mass easier, resulting in slower rotating core during collapse, reducing angular energy for gamma ray bursts.
Galactic core starts with few metals like rest of galaxy, but more stars lead to more supernovae enriching metals, lowering gamma ray burst rate.
Outskirts of galaxy have few metals and stars, reducing chance of gamma ray bursts, creating green zones.
Intermediate radii between core and outskirts create deadly sweet spot with enough stars and few metals for significant gamma ray bursts.
Sun's location in green zone ensures safety, but in the past, when sun formed, area was becoming hospitable.
Galactic Habitable Zone includes planet formation, planet retention, and metallicity, with debates on correlation between metallicity and planet formation.
Galactic bulge may be too dense for stable earth-like orbits due to close stellar encounters, potentially disturbing planetary systems.
Supernovae and planet formation may not solely determine Galactic Habitable Zone, but dense galactic bulge and gamma ray bursts could be significant factors.
Adaptability of life suggests different rates of mass extinctions may not hinder evolution of intelligent life, emphasizing the need for firmer evidence before accepting theories like the Galactic Habitable Zone.