8 billion-year-old radio signal reaches Earth.
CNN
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Astronomers have detected a mysterious blast of radio waves that have taken 8 billion years to reach Earth. The fast radio burst is one of the most distant and energetic ever observed.
Fast radio bursts, or FRBs, are intense, millisecond-long bursts of radio waves with unknown origins. The first FRB was discovered in 2007, and since then, hundreds of these quick, cosmic flashes have been detected coming from distant points across the universe.
The burst, named FRB 20220610A, lasted less than a millisecond, but in that fraction of a moment, it released the equivalent of our sun’s energetic emissions over the course of 30 years, according to a study published Thursday in the journal Science.
Many FRBs release super bright radio waves lasting only a few milliseconds at most before disappearing, which makes fast radio bursts difficult to observe.
Radio telescopes have helped astronomers trace these quick cosmic flashes, including the ASKAP array of radio telescopes, located on Wajarri Yamaji Country in Western Australia. Astronomers used ASKAP to detect the FRB in June 2022 and determine where it originated.
This artist's concept shows what the exoplanet WASP-17 b could look like.
WASP-17 b, also called Ditsö̀, is a hot gas giant that orbits its star at a distance of just 0.051 AU (about 4.75 million miles, or one-eighth the distance between Mercury and the Sun), completing one full circuit in about 3.7 Earth-days. The system lies within the Milky Way, about 1,300 light-years from Earth, in the constellation Scorpius.
With a volume more than seven times that of Jupiter and a mass less than one-half of Jupiter, WASP-17 b is an extremely puffy planet. Its short orbital period, large size, and thick, extended atmosphere make it ideal for observation using transmission spectroscopy, which involves measuring the effects of the planet's atmosphere on the starlight filtering through it.
WASP-17 b's atmosphere is composed primarily of hydrogen and helium, along with small amounts of water vapor and hints of carbon dioxide and other molecules. Observations of 5- to 12-micron infrared light from Webb's MIRI (Mid-Infrared Instrument) show that WASP-17 b's atmosphere also contains clouds made of nanocrystals of quartz (SiO2).
WASP-17 b is tidally locked and has a retrograde orbit. Its temperature ranges from about 1,000 kelvins (1,350 degrees F or 725 degrees C) on the cooler nightside to nearly 2,000 kelvins (3,150 degrees F or 1,725 degrees C) on the side in permanent daylight.
The star, WASP-17 (also called Diwö), is an F-type star: slightly larger, more massive, hotter, and whiter than the Sun.
This artist's concept is based on new data gathered by MIRI as well as previous observations from other ground- and space-based telescopes, including NASA's Hubble and retired Spitzer space telescopes. Webb has not captured any images of the planet.
Quartz crystals detected swirling in an exoplanet’s atmosphere
“Using ASKAP’s array of (radio) dishes, we were able to determine precisely where the burst came from,” said study coauthor Dr. Stuart Ryder, astronomer at Macquarie University in Australia, in a statement. “Then we used (the European Southern Observatory’s Very Large Telescope) in Chile to search for the source galaxy, finding it to be older and (farther) away than any other FRB source found to date and likely within a small group of merging galaxies.”
The research team traced the burst to what appears to be a group of two or three galaxies that are in the process of merging, interacting and forming new stars. This finding aligns with current theories that suggest fast radio bursts may come from magnetars, or highly energetic objects that result from the explosions of stars.
Scientists believe that fast radio bursts may be a unique method that can be used to “weigh” the universe by measuring the matter between galaxies that remains unaccounted for.
“If we count up the amount of normal matter in the Universe — the atoms that we are all made of — we find that more than half of what should be there today is missing,” said study coauthor Ryan Shannon, a professor at Swinburne University of Technology in Australia, in a statement. “We think that the missing matter is hiding in the space between galaxies, but it may just be so hot and diffuse that it’s impossible to see using normal techniques.”
So far, the results of current methods used to estimate the universe’s mass don’t agree with one another, which suggests the entire scope of the universe isn’t included.
Here is the link to the article:
https://www.cnn.com/2023/10/19/world/distant-ancient-fast-radio-burst-scn
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