Euler, a genuis

* Biography
http://press.princeton.edu/titles/10531.html

Leonhard Euler:Mathematical Genius in the EnlightenmentRonald S. Calinger


* economist, 2016-01-09

* http://eulerarchive.maa.org

* https://ja.wikipedia.org/wiki/レオンハルト・オイラー

科学衛星読みもの by Yuasa

http://www-utheal.phys.s.u-tokyo.ac.jp/~yuasa/wiki/index.php/科学衛星読みもの

特に日本のX線天文衛星について。

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すざく」衛星をより理解して、楽しく、意義を感じながら、衛星運用当番や、日々のデータ解析を行うための、読みもの。

現象論的な説明ではなくて、なぜそうなっているか、背景にどういう歴史があるかに重点をおいて、図・写真をたくさん使って説明する。

ASTRO-H in news

* 2015-12-02
http://news.mynavi.jp/articles/2015/12/02/astro-h/
報道公開を基にしている。
「すざく」でのXRSの失敗原因などについても説明されている。

Now there’s a look in your eyes, like black holes in the sky

The economist

The universe’s darkest denizens are being dragged into the light

Jan 9th 2016  | KISSIMMEE, FLORIDA | From the print edition

http://goo.gl/SvReMA

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Working out how black holes affect galactic growth, though, is not the same as finding out what is happening in the vicinity of the holes themselves. Here, matter is circling close to a black hole’s point of no return, the “event horizon” whose radius was described by Schwarzschild’s calculations. And next month, JAXA, Japan’s space agency, will launch Astro-H, a telescope that will help to do this. It can detect X-rays of exceptionally high energies. As material slips ever closer to the event horizon, the precise details of its X-ray output are a signal of how it is moving. Astro-H will be able to measure this radiation, and thus infer that motion with unprecedented precision. This will permit researchers to measure unambiguously, for the first time, how fast a black hole is spinning. That, in turn, permits tests of Einstein’s general theory of relativity—the very theory that Schwarzschild used to put black holes on solid mathematical ground—that have remained out of reach until now.

ASTRO-H JAXA page

http://fanfun.jaxa.jp/countdown/astro_h/index.html

from
http://jda-strm.tksc.jaxa.jp/archive/photo/P100010525/75e3f794d404a7e6a7c070d94dba2a51.jpg