A SIGNIFICATIVE FRACTION OF BARYONS RESIDE IN THE FILAMENTS OF THE COSMIC WEB

(Credit: NASA, ESA, and E. Hallman (University of Colorado, Boulder)

Observations of the cosmic microwave background indicate that baryons (protons, neutrons, etc., - the ordinary matter just to understand) occupies only 5% of the total energy content of the Universe (95% is dark matter and dark energy). However in the local universe approximately half of this "ordinary" matter it has never been observed.

A group of astrophysicists
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to know more:
(http://arxiv.org/abs/1512.00454)
(http://www.nature.com/nature/journal/v528/n7580/full/nature16058.html)
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has experimentally verified that the missing mass (ordinary) does not fill the space homogeneously but it is concentrated in large-scale filamentary structures that make up the so-called cosmic web with temperatures between 10^5 to 10^7 degrees. This gas has been heated up by the cluster's gravitational pull and is now feeding its core. The filamentous structures intersect at the nodes creating a structure that visually recalls the network of neurons of the nervous system.

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ORBITAL PERIODS OF THE PLANETS

For orbital period generally we refer to the sidereal period, that is the temporal cycle that it takes an object to make a full orbit, relative to the stars. This is the orbital period in an inertial (non-rotating) frame of reference (365,25 days for the earth).

A Sapphire Super-Earth

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CONTAMINATION BY SUPERNOVAE IN GLOBULAR CLUSTERS

Credit: ALMA (ESO/NAOJ/NRAO)/Alexandra Angelich (NRAO/AUI/NSF) Only a small amount of the supernovae products remains trapped within globular clusters and this "catch" only occurs in the most massive cases (mass cluster ≥ 10^6 solar masses).

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