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Why can't NASA just rebuild the Saturn V? 🚀 The plans still exist. What's gone is the hand know-how. In 2013 NASA engineers took F-1 engine parts apart, 3D-scanned them, laser-printed new ones and fired the gas generator for 20 seconds. It worked. #SaturnV #NASA #Apollo

How Apollo got to the Moon without refuelling:

Arizona doesn't change its clocks. The Navajo Nation inside it does. The Hopi land inside that doesn't. And a Navajo island inside Hopi does ⏰ On Highway 264 in summer, the local time changes 6 times in under 100 miles. #DaylightSavingTime #Arizona #Maps

Our video on where Silicon Valley really is:

Why don't airplane tires pop when they land? ✈️ Each 737 main tire carries ~40,000 lb and hits the runway at ~160 mph. It's pumped to ~200 psi, six times a car tire, so it barely bends and stays cool. And plugs melt before it can burst. #AvGeek #Aviation #Boeing

Our video on why the 737 flies with its wheels showing:

Why is NASA going to the Moon's south pole? 🌕 The Moon is barely tilted, so some crater floors there haven't seen the Sun in about two billion years. They're colder than Pluto and hold frozen water: drinking water, air and rocket fuel. #NASA #Artemis #Moon

Our video on how Apollo got home from the Moon with almost no fuel:

Ship traffic through the Strait of Magellan is up 70%+ because a drought is choking the Panama Canal 🚢 Every ship that crosses uses about 52 million gallons of fresh water from Gatun Lake, and the lake only refills with rain. #PanamaCanal #Shipping #Geography

Our video on why planes don't fly in straight lines:

What are those pods under a Boeing 737's wing? ✈️ They cover the curved rails the flaps slide out on. For landing the flaps move back and tip down, so a 737 can come in at about 160 mph instead of roughly 60 mph faster. #Boeing #AvGeek #Aviation

Our video on why the 737 has a little fin on its engine:

The last audio from the Learjet 60 that crashed in Greenacres, Florida on Sunday. All nine people on board were killed, including two young children. The opening is a reconstruction from the jet's real ADS-B track. The NTSB is investigating; the cause is not known. Our thoughts are with their families.

Where is Silicon Valley, really? 🗺️ It's not a city and not on any official map. San Francisco has Salesforce, Uber, Airbnb and OpenAI, but the real Silicon Valley is the Santa Clara Valley: Apple, Google, Nvidia, Intel and more. #SiliconValley #Tech #Maps

Our video on why Apple waited 16 years for a touchscreen Mac:

Why do the Boeing 787's wings bend so much? ✈️ On the ground they hang almost flat, in the air the tips curl way up. The carbon-fibre wings flex like a giant fishing rod, and in Boeing's test they rose about 25 feet without breaking. #Boeing #AvGeek #Aviation

Our video on why the 737 MAX has split wingtips:

How does Face ID know it's really you? 👀 Your iPhone covers your face in 30,000+ invisible infrared dots, and an infrared camera reads where they land to build a 3D map of your face. That's why a flat photo can't fool it. #FaceID #iPhone #HowItWorks

How did Apollo get home from the Moon with almost no fuel? 🌕🚀 Leaving the Moon is easy: a sixth of Earth's gravity, no air. One 2.5-minute burn behind the Moon, then Earth pulls you home for 2.5 days, and the air does the braking for free. #NASA #Apollo #Space

Why space capsules aren't pointy: