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How old were you when you found out that iPhone has a built-in feature that can reduce motion sickness while you’re a passenger in a car?
How it works:
How it works:
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Life tip: Once you load your dishwasher, tap the spray arms to make them turn. This way you will notice if they would get stuck, compromishing the washing result.
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The first transatlantic telegraph cable (1858) worked for 3 weeks before failing.
The cause: an engineer applied 2,000 volts to speed transmission, burning out the insulation.
It took 8 years to lay a cable that lasted.
When it worked, the first transatlantic message took 17 hours.
Today a packet crosses the Atlantic in 60 milliseconds.
The cause: an engineer applied 2,000 volts to speed transmission, burning out the insulation.
It took 8 years to lay a cable that lasted.
When it worked, the first transatlantic message took 17 hours.
Today a packet crosses the Atlantic in 60 milliseconds.
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The sky is blue because of a phenomenon called Rayleigh scattering.
Sunlight contains all visible wavelengths. In vacuum, they travel together.
In the atmosphere, photons collide with nitrogen and oxygen molecules.
Shorter wavelengths (blue: ~450nm) scatter far more than longer ones (red: ~700nm).
The scattering intensity is proportional to 1/wavelength⁴.
Blue scatters ~5.5× more than red.
So blue light scatters in all directions across the sky. Red light passes through more directly.
At sunset, sunlight travels through much more atmosphere. Most of the blue has scattered away. Only red and orange reach you.
The same physics that makes sunsets red also makes the deep ocean appear blue, water absorbs red wavelengths, leaving blue to reflect back.
Sunlight contains all visible wavelengths. In vacuum, they travel together.
In the atmosphere, photons collide with nitrogen and oxygen molecules.
Shorter wavelengths (blue: ~450nm) scatter far more than longer ones (red: ~700nm).
The scattering intensity is proportional to 1/wavelength⁴.
Blue scatters ~5.5× more than red.
So blue light scatters in all directions across the sky. Red light passes through more directly.
At sunset, sunlight travels through much more atmosphere. Most of the blue has scattered away. Only red and orange reach you.
The same physics that makes sunsets red also makes the deep ocean appear blue, water absorbs red wavelengths, leaving blue to reflect back.
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1. Think of a number
2. Double it
3. Add 6
4. Divide it in half
5. Subtract the number you started
6. The answer is 3
7. Correct?
2. Double it
3. Add 6
4. Divide it in half
5. Subtract the number you started
6. The answer is 3
7. Correct?
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Believe it or not, but
100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002569
is prime.
100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002569
is prime.
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The Gotthard Base Tunnel (Switzerland, 2016) is the longest and deepest railway tunnel on Earth.
57.1 km long. Up to 2,300 metres below the Alps.
At that depth, the rock temperature reaches 46°C.
Building it required cooling the tunnel air to keep workers alive.
57.1 km long. Up to 2,300 metres below the Alps.
At that depth, the rock temperature reaches 46°C.
Building it required cooling the tunnel air to keep workers alive.
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In Nigeria, solar panels are the new wedding gift.
Forget toasters and bedsheets. Newlyweds are adding solar panels, inverters, and batteries to their registries.
Forget toasters and bedsheets. Newlyweds are adding solar panels, inverters, and batteries to their registries.
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The Channel Tunnel: 50.5 km long, running 75 metres below the seabed.
Built by drilling from both sides, France and England, meeting in the middle with less than 50cm of error.
How? Laser-guided tunnel boring machines, adjusted daily by GPS and gyroscopes.
11,000 workers. 6 years (1988–1994). 13 deaths during construction.
Built by drilling from both sides, France and England, meeting in the middle with less than 50cm of error.
How? Laser-guided tunnel boring machines, adjusted daily by GPS and gyroscopes.
11,000 workers. 6 years (1988–1994). 13 deaths during construction.
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Life tip: extend the life of your hot water heater by replacing the sacrificial anode every 3-5 years. It's a DIY job that can extend the life of your tank.
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How do you steer a spacecraft that's 24 billion km away?
The answer is radio timing – precise to nanoseconds.
NASA's Deep Space Network sends a signal. It bounces off the spacecraft. The round-trip delay (measured to 1 nanosecond) gives the distance.
At 24 billion km, a signal takes 22 hours one way.
So you don't steer in real time.
You calculate the trajectory months in advance, fire the thrusters at exactly the right moment, and then wait.
Voyager 1's thrusters haven't been used since 1980. NASA fired them again in 2017 (after 37 years of idle) and they worked.
The Deep Space Network was designed in 1958. It still communicates with spacecraft launched in 1977.
The answer is radio timing – precise to nanoseconds.
NASA's Deep Space Network sends a signal. It bounces off the spacecraft. The round-trip delay (measured to 1 nanosecond) gives the distance.
At 24 billion km, a signal takes 22 hours one way.
So you don't steer in real time.
You calculate the trajectory months in advance, fire the thrusters at exactly the right moment, and then wait.
Voyager 1's thrusters haven't been used since 1980. NASA fired them again in 2017 (after 37 years of idle) and they worked.
The Deep Space Network was designed in 1958. It still communicates with spacecraft launched in 1977.
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For 30 years, Pioneer 10 and 11 drifted slightly off course, unexplained by any known force.
Physicists called it the Pioneer anomaly. Some thought it proved new physics.
In 2012, researchers solved it: the spacecraft's own heat radiating asymmetrically was pushing them off course.
Physicists called it the Pioneer anomaly. Some thought it proved new physics.
In 2012, researchers solved it: the spacecraft's own heat radiating asymmetrically was pushing them off course.
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The observable universe: 93 billion light-years across.
The Milky Way: 100,000 light-years across.
That's 0.0001% of the observable universe's diameter.
Earth to the nearest star (Proxima Centauri): 4.24 light-years.
Voyager 1 (fastest object humans have ever launched): 61,500 km/h.
At that speed, Proxima Centauri: 75,000 years away.
The entire observable universe contains an estimated 2 trillion galaxies.
The Milky Way: 100,000 light-years across.
That's 0.0001% of the observable universe's diameter.
Earth to the nearest star (Proxima Centauri): 4.24 light-years.
Voyager 1 (fastest object humans have ever launched): 61,500 km/h.
At that speed, Proxima Centauri: 75,000 years away.
The entire observable universe contains an estimated 2 trillion galaxies.
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Scientists simulated the entire universe and found something striking.
The Milky Way sits in one of the best regions for life to exist.
What makes it special:
• Distance from galactic centre: far enough to avoid lethal radiation from the core, close enough for heavy elements (iron, carbon) formed in old stars.
• Spiral arm location: low star density means fewer nearby supernovae.
• Age: old enough for rocky planets to form, young enough for stars to still be burning stably.
SciTechDaily, Oct 18 2026.
The Milky Way sits in one of the best regions for life to exist.
What makes it special:
• Distance from galactic centre: far enough to avoid lethal radiation from the core, close enough for heavy elements (iron, carbon) formed in old stars.
• Spiral arm location: low star density means fewer nearby supernovae.
• Age: old enough for rocky planets to form, young enough for stars to still be burning stably.
SciTechDaily, Oct 18 2026.
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MIT has the world's largest public collection of science fiction. Anyone can browse the MIT Science Fiction Society's library or become a member to borrow books.
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