star formation tagged posts

Space Oddity: Uncovering the Origin of the Universe’s Rare Radio Circles

Faint blue circles of light against a starry space background.
Odd radio circles, like ORC 1 pictured above, are large enough to contain galaxies in their centers and reach hundreds of thousands of light years across. (cr: Jayanne English / University of Manitoba)

Outflowing galactic winds from exploding stars may explain the enormous rings. Astronomers believe they may have found the origin of the universe’s giant odd radio circles: they are shells formed by outflowing galactic winds, possibly from massive exploding stars known as supernovae.

t’s not every day astronomers say, “What is that?” After all, most observed astronomical phenomena are known: stars, planets, black holes and galaxies...

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Astronomers find Cosmic Rays driving Galaxy’s Winds

Credit: Institute for Research in Fundamental Sciences- IPM & European Southern Observatory (ESO)

Astronomers using the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) have discovered an important new clue about how galaxies put the brakes on vigorous episodes of star formation. Their new study of the neighboring galaxy M33 indicates that fast-moving cosmicray electrons can drive winds that blow away the gas needed to form new stars.

Such winds are responsible for slowing the rate of star formation as galaxies evolve over time. However, shock waves from supernova explosions and energetic, black hole-powered jets of material coming from galactic cores have been considered the primary drivers of those winds...

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ALMA discovers Birth Cry from a Baby Star in the Small Magellanic Cloud

Researchers at Osaka Metropolitan University have observed “baby stars” in the Small Magellanic Cloud, having an environment similar to the early universe. Toward one of the baby stars, they found molecular outflow, which has similar properties to those seen in the Milky Way galaxy, giving a new perspective on the birth of stars.

The heavy elements in interstellar matter significantly impact the mechanism of star formation. In the early universe, the abundance of heavy elements was lower than in the present universe because there was not enough time for nucleosynthesis to produce heavy elements in stars. It has not been well understood how star formation in such an environment differs from present-day star formation.

An international team led by Professor Toshikazu Onishi, Osaka...

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Hubble finds Early, Massive Galaxies Running on Empty

These images are composites from NASA’s Hubble Space Telescope and the Atacama Large Millimeter/submillimeter Array (ALMA). The boxed and pullout images show two of the six, distant, massive galaxies where scientists found star formation has ceased due to the depletion of a fuel source – cold hydrogen gas. Hubble, together with ALMA, found these odd galaxies when they combined forces with the “natural lens” in space created by foreground massive galaxy clusters. The clusters’ gravity stretches and amplifies the light of the background galaxies in an effect called gravitational lensing. This phenomenon allows astronomers to use massive galaxy clusters as natural magnifying glasses to study details in the distant galaxies that would otherwise be impossible to see...
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