You’re reading Significant Digits, a daily digest of the numbers tucked inside the news.
The mass demonstrations in Hong Kong — which were started over a controversial extradition bill which would have allowed people to be sent to mainland China to stand trial, undermining Hong Kong’s freedoms, per its critics — have entered their 10th week. Over the weekend, police “fired teargas across the city” and shot rubber bullets, and protestors threw petrol bombs and bricks at police who were charging them with batons. [BBC]
40 billion times the sun
Astronomers have discovered the most massive black hole ever observed, in a galaxy called Holm 15A in the constellation Cetus some 700 million light years from Earth. A conservative estimate puts the black hole at 40 billion times more massive than our sun. There is also a black hole at the center of our Milky Way, but it is a pathetically puny 4 million times more massive than the sun. [MIT Technology Review]
$70,000 per minute
That’s how much money the Walmart-owning Walton family has made in the year since Bloomberg’s previous list of the world’s richest families. The Waltons top that list this year, with wealth of $190.5 billion. The Mars, Koch, Al Saud and Wertheimer (of the Chanel fashion house) families round out a top five. The 25 richest families in the world control $1.4 trillion, a figure which is up nearly a quarter from last year. [Bloomberg]
2 flips, 3 twists
All hail Simone Biles. The American gymnast etched herself even deeper in the annals of the sport recently, becoming the first woman in competition in the floor exercise to land a triple double — that’s two flips with three twists. She attempted another first later that same night: a double-double dismount, off of a balance beam, which she landed “with a slight hop.” The only trouble is that Biles already has two innovations named after her; they’re both, of course, called the Biles. [The New York Times]
Four books by the late J.D. Salinger — “The Catcher in the Rye,” “Nine Stories,” “Franny and Zooey” and “Raise High the Roof Beam, Carpenters and Seymour: An Introduction” — will be available for the first time on Tuesday as e-books. Salinger’s son has long insisted that other, as-yet-unpublished work by his father will also see the light of day, but that such an event may still be years away. [Associated Press]
50 meteors per hour
We’re going to fly through a bunch of space junk tonight and tomorrow, a fact which will manifest itself to us, the passengers of Spaceship Earth, as the Perseid meteor shower. Specifically, the Perseids happens as the Earth “passes through the debris trail of the comet Swift-Tuttle.” Peaking tonight and tomorrow night, some from a dozen to 50 meteors per hour will be visible to gazers across the U.S. [The Washington Post]
From ABC News:
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