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  2. Extinction (astronomy) - Wikipedia

    en.wikipedia.org/wiki/Extinction_(astronomy)

    This is similar to the effect seen when dust particles in the atmosphere of Earth contribute to red sunsets. [6] Broadly speaking, interstellar extinction is strongest at short wavelengths, generally observed by using techniques from spectroscopy. Extinction results in a change in the shape of an observed spectrum.

  3. What is a mass extinction, and why do scientists think we’re ...

    www.aol.com/brief-history-end-world-every...

    The Siberian Traps was a vast area of volcanic activity in Eurasia that led to the biggest mass extinction 252 million years ago. The distant mountains are remains of basalt lava flows, and the ...

  4. Extinction event - Wikipedia

    en.wikipedia.org/wiki/Extinction_event

    An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the biodiversity on Earth. Such an event is identified by a sharp fall in the diversity and abundance of multicellular organisms .

  5. Impact event - Wikipedia

    en.wikipedia.org/wiki/Impact_event

    The last such mass extinction led to the demise of the non-avian dinosaurs and coincided with a large meteorite impact; this is the Cretaceous–Paleogene extinction event (also known as the K–T or K–Pg extinction event), which occurred 66 million years ago. There is no definitive evidence of impacts leading to the three other major mass ...

  6. Gamma-ray burst - Wikipedia

    en.wikipedia.org/wiki/Gamma-ray_burst

    This may be self-evident, since a gamma-ray burst in the Milky Way pointed directly at Earth would likely sterilize the planet or effect a mass extinction. [13] The Late Ordovician mass extinction has been hypothesised by some researchers to have occurred as a result of such a gamma-ray burst. [14] [15] [16]

  7. Stellar wind - Wikipedia

    en.wikipedia.org/wiki/Stellar_wind

    Stellar winds from main-sequence stars do not strongly influence the evolution of lower-mass stars such as the Sun. However, for more massive stars such as O stars, the mass loss can result in a star shedding as much as 50% of its mass whilst on the main sequence: this clearly has a significant impact on the later stages of evolution.

  8. Shiva hypothesis - Wikipedia

    en.wikipedia.org/wiki/Shiva_Hypothesis

    The Sun's passage through the higher density spiral arms of the galaxy, rather than its passage through the plane of the galaxy, could hypothetically coincide with mass extinction on Earth. [5] However, a reanalysis of the effects of the Sun's transit through the spiral structure based on CO data has failed to find a correlation.

  9. Cretaceous–Paleogene extinction event - Wikipedia

    en.wikipedia.org/wiki/Cretaceous–Paleogene...

    The Cretaceous–Paleogene (K–Pg) extinction event, [a] also known as the K–T extinction, [b] was the mass extinction of three-quarters of the plant and animal species on Earth [2] [3] approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs.