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martyb [soylentnews.org] writes:

A newly-released article in the Journal Nature reports on research which claims it has found the 'missing matter' that prior research had failed to identify.

The abstract [nature.com]'s Editor's summary succinctly notes:

This paper reports the discovery, with the Parkes radio telescope, of a fast radio burst, FRB 150418. A multi-wavelength multi-telescope follow-up study detected a radio transient two hours after the initial burst, lasting about six days before fading to a quiescent level. The authors interpret this fading source as the afterglow of the FRB. Fast radio bursts are transient radio pulses lasting only a few milliseconds and previously it has not been possible to localize such a burst and determine a redshift. The source of FRB 150418 is identified as an elliptical galaxy with redshift of 0.492.

An article at Phys.org, New fast radio burst discovery finds 'missing matter' in the universe [phys.org], elaborates:

An international team of scientists using a combination of radio and optical telescopes has for the first time managed to identify the location of a fast radio burst [wikipedia.org], allowing them to confirm the current cosmological model of the distribution of matter in the universe.

[...] The team … used the National Astronomical Observatory of Japan (NAOJ)'s 8.2-m Subaru optical telescope in Hawaii to look at where the signal came from, and identified an elliptical galaxy some 6 billion light years away. "It's the first time we've been able to identify the host galaxy of an FRB" added Dr Keane. The optical observation also gave them the redshift measurement (the speed at which the galaxy is moving away from us due to the accelerated expansion of the universe), the first time a distance has been determined for an FRB.

FRBs show a frequency-dependent dispersion, a delay in the radio signal caused by how much material it has gone through. "Until now, the dispersion measure is all we had. By also having a distance we can now measure how dense the material is between the point of origin and Earth, and compare that with the current model of the distribution of matter in the universe" explains Dr Simon Johnston, co-author of the study, from CSIRO's Astronomy and Space Science division. "Essentially this lets us weigh the universe, or at least the normal matter it contains."

In the current model, the universe is believed to be made of 70% dark energy, 25% dark matter and 5% 'ordinary' matter, the matter that makes everything we see. However, through observations of stars, galaxies and hydrogen, astronomers have only been able to account for about half of the ordinary matter, the rest could not be seen directly and so has been referred to as 'missing'.

"The good news is our observations and the model match, we have found the missing matter" explained Dr Keane. "It's the first time a fast radio burst has been used to conduct a cosmological measurement."

(Emphasis added.)

I find this kind of research to be absolutely astounding. The speed of light is so fast that one could make seven laps around the Earth at the equator in less than one second. (Compare that to how long your last flight took!) This research was based on a signal that took 6 billion years to reach Earth. If faster-than-light travel were possible, and one could travel one light year's distance (9.46 * 10¹⁵ meters) in one second, it would still take over 190 years to cover that distance! Douglas Adams said it best: space is BIG! [quotationspage.com]

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