Hiroshi Nagai

6 articles · 30 co-authors · latest: 2026-07-17
17,880 citations · h-index 51 · 211 papersData: Semantic Scholar

We have retold 6 papers by this author. 1 of them with a full read. most often about: black hole, dark matter, Accretion disk. 30 co-authors across our retellings.

Links in the knowledge graph
High Energy2026-01-012 minarXiv:2601.00394express
A Black Hole's Shadow Betrays Its Spin
In 2019, astronomers unveiled the first-ever image of a black hole's shadow — a dark void encircled by a lopsided orange ring. This is the supermassive black hole at the heart of galaxy M87, 55 million light-years away. The ring isn't just glowing: one side is noticeably brighter than the other, like a campfire burning unevenly, with flames leaping higher on one side.
High Energy2026-01-191 minarXiv:2601.13356express
The Shadow of a Black Hole and Its Invisible Tail
Radio telescopes scattered across the globe pick up waves from distant black holes. But two telescopes placed almost side by side see only a blurry blob — fine details are beyond them. Usually, such pairs are considered useless and discarded. But that's a mistake: even a blurry blob holds clues.
Galaxies2026-03-171 minarXiv:2603.16796express
A Magnetic Map Around a Black Hole
Radio waves passing through magnetized gas have their polarization slightly rotated, like a compass needle deflecting near a magnet. This rotation, called the Faraday effect, revealed the invisible environment around the supermassive black hole in galaxy NGC 1275.
Galaxies2026-04-111 minarXiv:2604.10287express
The Heart of the Milky Way Flickers in Polarized Light
At the center of the Milky Way lies the supermassive black hole Sagittarius A*. It is four million times more massive than the Sun, but by cosmic standards it behaves quietly: it only occasionally flares up when it swallows a clump of gas.
High Energy2026-06-082 minarXiv:2606.08931express
Cosmic Jet Slams into a Cloud
A fire hose blasts into a snowdrift. The water doesn't just shove the snow aside — at the point of impact, spray, steam, and a roar are born. That's roughly how jets behave: narrow streams of matter shooting out from around a black hole at enormous speeds.
Galaxies2026-07-173 minarXiv:2607.16104