<
https://www.quantamagazine.org/to-see-black-holes-in-detail-she-uses-echoes-like-a-bat-20240212/>
"Unlike many astronomers, Erin Kara didn’t grow up star-struck. “I don’t have
that story of being that little kid staring up at the stars and wanting to do
this, which gave me some anxiety,” she said. “Did that make me a fake?”
But after discovering astrophysics as an undergraduate, Kara was hooked. Now an
observational astrophysicist at the Massachusetts Institute of Technology, she
visits mind-bending territory. Like an astronaut in the film Interstellar, she
explores the regions near gargantuan black holes. Her goal is to better
understand how those black holes behave and how they continually reshape
galaxies across the universe.
Packed with mass equal to millions or billions of suns, supermassive black
holes lurk at the center of nearly every galaxy. Energetically, these black
holes are like galaxies’ dark, beating hearts.
“They’re not just ornamental. They’re not just sitting there passively,” Kara
said. “They’re actually dictating how the galaxy evolves and why the galaxy
looks the way that it does.”
Kara tries to understand the environment near these black holes, where most of
their energy is released. By carefully tracking the gas and plasma that swirls
near a black hole — forming what’s known as an accretion disk — she can
approximate the black hole’s mass, for example. That nearby gas and plasma can
also help reveal how feasting black holes create extreme cosmic structures such
as relativistic jets — gigantic beams of superheated plasma accelerated to
nearly the speed of light.
But there’s a huge problem that Kara and other researchers must overcome: These
target black holes are so far away that conventional imaging techniques can’t
resolve their immediate surroundings. To reconstruct the immediate environment
around a black hole, Kara turns to the X-ray light given off by the accretion
disk. She measures subtle delays in when that light reaches Earth. By doing so,
she can infer the structure of the gas and plasma with remarkable resolution.
Kara’s work on this method — called reverberation mapping — has exposed black
holes’ feeding frenzies in unprecedented detail, with findings that include the
first X-ray “echoes” ever seen from a black hole shredding a star. Kara
received the American Astronomical Society’s 2022 Newton Lacy Pierce Prize,
which recognizes outstanding achievements in observational astronomy over the
preceding five years.
Quanta Magazine recently spoke with Kara about her path into science, the
nuts and bolts of reverberation mapping, and the black holes that keep her up
at night. The interview has been condensed and edited for clarity."
Via
Future Crunch:
<
https://futurecrunch.com/good-news-tolerance-poland-sanitation-indonesia-restoration-dominican-republic/>
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
