Category Astronomy/Space

How the Universe got its Magnetic Field

How the universe got its magnetic field | MIT News
Visualization of filamentary seed magnetic fields emerging from large-scale motions of unmagnetized plasma in a first-principles numerical simulation. Credit: Muni Zhou et al

When we look out into space, all of the astrophysical objects that we see are embedded in magnetic fields. This is true not only in the neighborhood of stars and planets, but also in the deep space between galaxies and galactic clusters. These fields are weak—typically much weaker than those of a refrigerator magnet—but they are dynamically significant in the sense that they have profound effects on the dynamics of the universe. Despite decades of intense interest and research, the origin of these cosmic magnetic fields remains one of the most profound mysteries in cosmology.

In previous research, scientist...

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New Discovery about Distant Galaxies: Stars are Heavier than we thought

New discovery about distant galaxies: Stars are heavier than we thought
Left: best-fit temperature from 10 to 50 K vs. lookback time from a sample of 139,535 COSMOS2015 galaxies with S/N > 10 in the V band (Laigle et al. 2016). At each redshift, the distribution is individually normalized in order to emphasize the temperature distribution at all redshifts. With increased redshift, fewer galaxies are fit at lower temperatures. Right: boxcar-smoothed mean with standard deviation of best-fit gas temperature at different lookback times (with mean determined from objects in 2 Gyr width age bins and not including galaxies fit at the bounds of temperature range). The mean temperature increases from ∼28 to ∼36 K from present to 12 Gyr, while the spread decreases. Credit: The European Physical Journal E (2022). DOI: 10.1140/epje/s10189-022-00183-5

A team of Uni...

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Hubble reaches new Milestone in Mystery of Universe’s Expansion Rate

This collection of 36 images from NASA’s Hubble Space Telescope features galaxies that are all hosts to both Cepheid variables and supernovae. These two celestial phenomena are both crucial tools used by astronomers to determine astronomical distance, and have been used to refine our measurement of the Hubble constant, the expansion rate of the universe.

Completing a nearly 30-year marathon, NASA’s Hubble Space Telescope has calibrated more than 40 “milepost markers” of space and time to help scientists precisely measure the expansion rate of the universe — a quest with a plot twist.

Pursuit of the universe’s expansion rate began in the 1920s with measurements by astronomers Edwin P. Hubble and Georges Lemaître...

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AI reveals unsuspected Math underlying Search for Exoplanets

chart explaining gravitational microlensing
This infographic explains the light curve astronomers detect when viewing a microlensing event, and the signature of an exoplanet: an additional uptick in brightness when the exoplanet lenses the background star. (Image Credit: NASA / ESA / K. Sahu / STScI)

Artificial intelligence (AI) algorithms trained on real astronomical observations now outperform astronomers in sifting through massive amounts of data to find new exploding stars, identify new types of galaxies and detect the mergers of massive stars, accelerating the rate of new discovery in the world’s oldest science.

But AI, also called machine learning, can reveal something deeper, University of California, Berkeley, astronomers found: Unsuspected connections hidden in the complex mathematics arising from general relativity—...

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