According to recent calculations, dying stars emit massive "cocoons" of gas
that might rumble with gravitational waves.
Astronomers frequently listen for the ringing of black holes around the
cosmos ever since the first direct observation of the gravitational waves,
also known as gravitational waves, was published in 2016. Nearly 100
collisions between black holes (and occasionally neutron stars) have been
discovered by initiatives like the Laser Interferometer Gravitational-Wave
Observatory (better known as LIGO), which shook the cosmos and sent waves
through space.
But according to recent studies, dying stars' jets of roiling gas may soon
cause cocoons of rumbling gas to form in space, which LIGO may soon detect.
According to research presented this week at the 242nd meeting of the
American Astronomical Society, researchers at Northwestern University utilized cutting-edge computer
models of huge stars to demonstrate how these cocoons may emit gravitational
waves that are "impossible to ignore". Real-world research on these
reverberations may shed light on how violently massive stars die.
Massive stars that run out of fuel fall into black holes while
simultaneously ejecting enormous jets of extremely fast-moving particles.
The researchers reproduced these latter phases of a star's life in the hopes
that the jets may result in gravitational waves, but another phenomenon
seized the lead.
Ore Gottlieb, the study's principal investigator and an astronomer at Northwestern
University's Center for Interdisciplinary Exploration and Research in
Astrophysics, said in a
statement
that when he estimated the gravitational waves from the black hole's
proximity, he discovered another source that was interfering with his
calculations: the cocoon. The falling star's outer layers combine with the
powerful jets emitted from within to create the chaotic gas glob known as
the cocoon. Something large and asymmetrically moving is required to
generate gravitational waves, much like the turbulent material inside the
cocoon.
In order to escape, a jet must first dig its way out from the center of a
star, according to Gottlieb. "Imagine drilling a hole through a wall. Debris
leaks out of the wall when the rotating drill bit strikes it. That substance
receives energy from the drill bit. Similar to that, when the jet pierces
the star, stellar material heats up and spills out. This debris creates a
cocoon's warm layers.
The ripples the cocoon produced should be simple for LIGO to pick up on
during its subsequent series of measurements, according to Gottlieb's
estimates. Additionally, because cocoons produce light, astronomers may
learn more about them simultaneously using gravitational waves and
telescopes, a thrilling achievement known as multi-messenger
astronomy.
It will be a fascinating new peek into the interiors of stars and the end
of their lives if LIGO does observe a cocoon in the near future.
Additionally, it may be the first time that LIGO has been able to identify
gravitational waves coming from a single object rather than from the
collisions of two binary objects circling one another.
Gottlieb predicted that one day LIGO will discover the first non-binary
source of gravitational waves. "As of now, LIGO has only detected
gravitational waves from binary systems," he added. One of the first areas
we should seek for this kind of supply is cocoons.
A peer-reviewed publication has not yet published the team's study.
