The under-construction CHIME radio telescope may be the ultimate testing
ground for a new technique to chart large objects in the universe using
fast radio bursts
(Credit: Keith Vanderlinde)
Brief bursts of radio waves arriving from far off galaxies
could help cosmologists estimate cosmological distances and piece together a 3D
map of matter in the universe. A new technique proposed by two cosmologists
from University of British Columbia will offer an independent metric in
plotting the large structures of the cosmos.
Fast radio bursts are radio wave signal that last only a few
milliseconds and originate outside our own galaxy. They spread out and separate
according to their wavelengths as they travel through space. The longer the
wavelength s tend to arrive later than the shorter ones, and this delay between
arrival times may tell us not only the distance traveled by waves but also what
materials (stars, gas, dark matter) lie between earth and the source of the
burst.
Only 10 such burst has been recorded in eight years since
the first was observed, but astronomers believe there could be thousands every
day. The researchers estimate that measurements
of around 10000 fast radio bursts would be needed to account for variation in
electron density, which will otherwise result in higher density regions
appearing farther away and lower density regions appearing closer.
Beyond that, the only major uncertainty about the new
technique’s viability is something called dispersion. This relates to how
electromagnetic radiation travels at different speeds through space according
to its wavelength and electron density. It’s the phenomenon that the fast radio
burst calculations rests upon.
It’s not only produced by intergalactic electron density,
through, but also by environmental properties of our galaxy and at the source
of the fast radio burst. The former can be measured and accounted for, but the
latter could prove troublesome if analysis reveal big variations in fast radio
burst emissions.
If it does work out, the new method would be a welcome
addition to the tiny roster of existing options for estimating cosmological
distances, of which redshift measurement are the leading choice. (as the
universe expands, stars move farther away, and we can infer distances from
measuring how much the wavelengths shifts towards the red end of the spectrum)
despite the inherent shortcoming in how the Hubble space telescope detects
them.
Brief bursts of radio waves arriving from far off galaxies
could help cosmologists estimate cosmological distances and piece together a 3D
map of matter in the universe. A new technique proposed by two cosmologists
from University of British Columbia will offer an independent metric in
plotting the large structures of the cosmos.
Fast radio bursts are radio wave signal that last only a few
milliseconds and originate outside our own galaxy. They spread out and separate
according to their wavelengths as they travel through space. The longer the
wavelength s tend to arrive later than the shorter ones, and this delay between
arrival times may tell us not only the distance traveled by waves but also what
materials (stars, gas, dark matter) lie between earth and the source of the
burst.
Only 10 such burst has been recorded in eight years since
the first was observed, but astronomers believe there could be thousands every
day. The researchers estimate that measurements
of around 10000 fast radio bursts would be needed to account for variation in
electron density, which will otherwise result in higher density regions
appearing farther away and lower density regions appearing closer.
Beyond that, the only major uncertainty about the new
technique’s viability is something called dispersion. This relates to how
electromagnetic radiation travels at different speeds through space according
to its wavelength and electron density. It’s the phenomenon that the fast radio
burst calculations rests upon.
It’s not only produced by intergalactic electron density,
through, but also by environmental properties of our galaxy and at the source
of the fast radio burst. The former can be measured and accounted for, but the
latter could prove troublesome if analysis reveal big variations in fast radio
burst emissions.
If it does work out, the new method would be a welcome
addition to the tiny roster of existing options for estimating cosmological
distances, of which redshift measurement are the leading choice. (as the
universe expands, stars move farther away, and we can infer distances from
measuring how much the wavelengths shifts towards the red end of the spectrum)
despite the inherent shortcoming in how the Hubble space telescope detects
them.
Brief bursts of radio waves arriving from far off galaxies
could help cosmologists estimate cosmological distances and piece together a 3D
map of matter in the universe. A new technique proposed by two cosmologists
from University of British Columbia will offer an independent metric in
plotting the large structures of the cosmos.
Fast radio bursts are radio wave signal that last only a few
milliseconds and originate outside our own galaxy. They spread out and separate
according to their wavelengths as they travel through space. The longer the
wavelength s tend to arrive later than the shorter ones, and this delay between
arrival times may tell us not only the distance traveled by waves but also what
materials (stars, gas, dark matter) lie between earth and the source of the
burst.
Only 10 such burst has been recorded in eight years since
the first was observed, but astronomers believe there could be thousands every
day. The researchers estimate that measurements
of around 10000 fast radio bursts would be needed to account for variation in
electron density, which will otherwise result in higher density regions
appearing farther away and lower density regions appearing closer.
Beyond that, the only major uncertainty about the new
technique’s viability is something called dispersion. This relates to how
electromagnetic radiation travels at different speeds through space according
to its wavelength and electron density. It’s the phenomenon that the fast radio
burst calculations rests upon.
It’s not only produced by intergalactic electron density,
through, but also by environmental properties of our galaxy and at the source
of the fast radio burst. The former can be measured and accounted for, but the
latter could prove troublesome if analysis reveal big variations in fast radio
burst emissions.
If it does work out, the new method would be a welcome
addition to the tiny roster of existing options for estimating cosmological
distances, of which redshift measurement are the leading choice. (as the
universe expands, stars move farther away, and we can infer distances from
measuring how much the wavelengths shifts towards the red end of the spectrum)
despite the inherent shortcoming in how the Hubble space telescope detects
them.
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