Josh Hopkins

A person born in China at the end of WWII saw China's power rise as its working age population tripled in their lifetime.

But now it has plateaued.

A person born today will see that growth reversed. China's working age population will drop by 1 million people per month for decades.

I get that the news cycle is packed right now, but I just heard from a colleague at the Smithsonian that this is fully a GIANT SQUID BEING EATEN BY A SPERM WHALE and it’s possibly the first ever confirmed video according to a friend at NOAA

10 YEAR OLD ME IS LOSING HER MIND (a thread 🧵)

Screenshot of article excerpt: The Education Department also was concerned about other words in the application, said Adrian Klenz, who works with deafblind adults in the state. He said he has talked with state officials about the discontinuation of the grant. “I was told that apparently the administration is going through past grants and two words were flagged: One was transition and one was privilege,” Klenz said. “Transition — transitioning from childhood to adulthood. Privilege came up because a parent wrote a glowing review of staff that said what a privilege it was to work with them.” ProPublica obtained a copy of the grant application and confirmed that those words were included.

The Dept. of Education has pulled funding for programs in 8 states that support students with both hearing and vision loss.

A staffer at one program says he was told the Trump admin. took issue with 2 words on the grant application: “transition" and “privilege": www.propublica.org/article/trum...

Vaccines are battle training for your immune system. If you could give it intel on the enemy, why would you withhold that? Give me ALL the vaccines! I want to be prepared for everything!

The main thing Arthur C. Clarke missed is that an HS-601 or A2100 comsat does not have “living quarters, laboratories, and everything needed for the comfort of its crew.” There are no vacuum tubes that need to be replaced by on-site technicians

Multi-stage chemical rockets launched dozens of solar powered geostationary satellites, each with multiple reflectors a few meters across that use high frequency spot beams and 50-100 W amplifiers to send hundreds channels of television to fixed receivers on the ground about 18 inches across.

Building and launching a satellite would be expensive, but it would be cheaper than building a ground based network to cover such a large area.

This overall concept is a remarkably accurate description of direct broadcast TV satellites built starting in the mid 1990s.

Only 50 W per channel would be needed to transmit TV to a parabolic receiver about a foot across. The satellite could send many transmissions using the same few reflectors.

Power could be provided by solar energy, but batteries would be required for an hour or so each day around the equinoxes.

Instead of an omnidirectional antenna, a reflector only a meter or so across could concentrate the beam on the hemisphere of Earth for radio waves of 3000 megacycles per second (we now call that “S-band”). Larger reflectors could produce a smaller beam to cover a single country or a smaller region.

A single satellite could cover almost half the globe. Three would be required for world-wide service, but “more could be readily utilized.”
Specific longitudes over Europe, Asia, and the Americas would be most suitable.

There was not yet any evidence that radio waves actually could penetrate the ionosphere, so this should be tested by a surplus V2 rocket (they had just become surplus a few weeks before!), or by bouncing radar off the Moon. (The US Army did both the following year.)

Reaching this orbit requires multi-stage rockets but is feasible with known propellants like oxygen and hydrogen.

A satellite in stationary orbit “could act as a repeater to relay transmissions to any two points on the hemisphere beneath using any frequency which will penetrate the ionosphere.”

A satellite in a specific orbit of radius 42,000 km, positioned over the equator, would rotate with the Earth and “would remain fixed in the sky of a whole hemisphere”.

Because the orbit appeared stationary, an antenna on Earth “once set up, could remained fixed indefinitely.”

Future television broadcast networks would be much harder and more expensive to build than FM or shortwave radio because high frequency signals don’t travel over the horizon.

New rocket technology could reach orbit “in a few more years”.

In 1945, Clarke was probably one of a handful of people on the planet who could design an orbit and a high frequency radio transmitter, even though he hadn’t yet been to college.

In his brief paper, Clarke explained the following points:

Clarke was the perfect person to invent GEO comsats. He was an early space nerd prone to calculating orbital mechanics for fun. And, he spent the war in the RAF developing radar technology and teaching it to new trainees.

Many people know Clarke “invented the geostationary communications satellite” but assume he only came up with the general concept. In fact, his 4 page paper is packed with prescient details. It’s worth reading for its historical significance and as an example of clear, succinct, technical writing.

80 years ago, as WWII was ending, a young RAF engineer and science fiction enthusiast named Arthur C. Clarke published a short piece titled “Extra-Terrestrial Relays" in the October 1945 issue of Wireless World. It changed the world.
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colour photo. A hummingbird hovers in front of a drogue-like fitting on a model KC-135, possibly 1:48 scale - suspended from a garage door or porch roof

apparently, yesterday was National Hummingbird Day, and it reminded me of something I saved off the other place a few years ago - someone (I’ve lost who, sorry) made this KC-135 Hummingbird feeder!

It got me thinking about a fighter-sized bird..

1/3

Here’s a picture of the Moon right now just in case weather or location do not permit you to see it.

I believe the point he's trying to make is that while electricity is energy, not all energy is electricity. So, if you provide oodles of electricity, it still wouldn't meet all our (non-electric) energy needs.

This is poorly conceived and described, for multiple reasons, but it's not a dumb point.

First powered flight of the Talon-A testbed, dropped off a pylon from a Stratolaunch 'Roc':
youtu.be/9UYj6jOXDV8
It's 8.5m long and under 3 tons, and it reached close to Mach 5 using its 22 kN kerolox rocket engine from Ursa Major.

It was the Kuybyshevsk refinery, not the neighboring Novokuybyshevsk refinery.

a 19th century embroidery sampler showing the solar system, the distance of the planets from the sun, and the length of time it takes each planet to circle the sun

Imagine the complicated and precious genius of the girl who made this embroidery sampler in 1811

The Solar System, sampler, unknown maker, 1811, England. Museum no. T.92-1939. Victoria and Albert Museum, London.

I have no idea if the movie is faithful to the book, and I haven't read the book in a few decades, but isn't the Cat in the Hat the cause of the problems in the first place? It seems odd to categorize a feline troublemaker as a "white savior" trope.

I wish to pass this magnificent tweet along for you to read.

Just realised the previous post's 2nd & 3rd were by Frank R Paul, which I posted 4 months ago on one of his anniversaries, so here's some more Hugo Gernsback-edited 'Science and Invention' illustrations from 1920-1921 (1&4 Howard V Brown, 2 George Wall, 3 [couldn't identify - possibly Frank R Paul):

Ah, did switching the primary to a different network also swap which channel is on the secondary tube? I can see how that would be more convenient than manually switching independent TVs.
I am old enough to remember when there were only four channels, just haven't seen one of these.

Is there a reason it makes sense to have all three screens in one set, rather than just buying two separate smaller TVs? They aren't sharing any major components are they?

Dark Star (1974): Scout spaceship exterior art by Ron Cobb.

Dark Star (1974): Scout spaceship, art by Ron Cobb