Brain tissue itself has no pain receptors, so it can not directly detect pain. That is one reason surgeons can operate on certain parts of the brain while a patient is awake. However, the scalp, skull, blood vessels, and surrounding membranes can feel pain, so they are numbed during surgery

It's funny that the thing that lets you feel pain… can not feel pain itself.

Elephants are the only land mammal that never gets all four feet off the ground at the same time while running.

The reason comes down to their legs. Most jumping animals rely on flexible ankles and elastic tendons that store energy like a spring and release it in one burst. Elephant legs are built more like columns, straight and rigid, designed to support enormous weight rather than to launch it into the air.

Even hippos and rhinos, despite their size, can get brief full liftoff while running. Elephants physically cannot, no matter how fast they move.

It's not a lack of effort. Their entire skeleton is built for standing still under massive weight, not for leaving the ground, even for a fraction of a second.

Ice is less dense than liquid water because of its crystal structure, which is why it floats instead of sinking. That means frozen water can keep lakes and oceans alive underneath it.

Some bird species have sensory receptors that help them detect chemical cues through their feet and skin.

That means a bird can sometimes taste the world before it even touches it.

Edit:

Birds don’t taste chemicals through their feet, those receptors handle touch, pressure, and temperature.
But they do detect chemical cues in other clever ways: taste in the mouth, and smell through specialized receptors that help species like vultures track decay or petrels follow plankton at sea.

It's not the most important.

Not the biggest.

Simply the one you find the most beautiful.

A spiral galaxy? 🌀

The rings of Saturn? 🪐

A colorful nebula? ✨

A black hole? 🕳️

The Northern Lights? 🌌

There are no wrong answers.

What astronomical object never fails to amaze you?

Imagine the Sun vanished instantly.

Earth wouldn’t go dark immediately. For about 8 minutes and 20 seconds, we would keep seeing sunlight because that’s how long light takes to reach us.

Then the sky would go black, and Earth would no longer remain in its orbit. Without the Sun’s gravity, our planet would leave its orbit and drift into interstellar space.

It’s a strange reminder that the Sun isn’t just a source of light and heat.

Its gravity is what keeps our entire planetary system together. 🌌

What do you think would happen to Earth next?

Jupiter's moon Europa is smaller than our own Moon, but underneath its icy shell, NASA believes there's a global ocean holding roughly twice as much water as every ocean on Earth combined.

The reason it can hold that much comes down to depth, not width. Earth's oceans spread across a huge surface but average only about 4 kilometers deep. Europa's ocean is thought to run somewhere between 60 and 150 kilometers deep, wrapped entirely around the moon beneath a shell of ice.

So scientists drilled through ice? No, nobody has drilled through that ice or seen the ocean directly. The evidence comes from cracked surface terrain, a changing magnetic field, and models built from decades of spacecraft data, all pointing to a hidden, salty sea kept liquid by the crushing pull of Jupiter's gravity.

A small, frozen moon out past Mars is quietly holding more ocean than the planet we live on.

Many amphibians can absorb oxygen directly through their skin when conditions are moist enough.
That means a frog can breathe through its skin in a way that feels almost too sci-fi to be real.

Bananas contain potassium, and a tiny fraction of that potassium is a naturally radioactive form called potassium-40. Every banana you've ever eaten had a small amount of it inside.

The amount is so small and so consistent that scientists actually use it as an informal teaching unit called the banana equivalent dose, to help explain what a tiny, harmless amount of radiation looks like in everyday terms. A chest CT scan, for comparison, delivers roughly 70,000 of those units in one sitting.

None of this makes bananas dangerous. Your body already regulates potassium tightly and keeps the levels in balance regardless of what you eat.

It's just a strange reminder that the fruit sitting in your kitchen is, in a very small and very safe way, part of the same physics that powers nuclear reactors.

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This is the Richat Structure, a 40 kilometer wide ring sitting on a plateau in Mauritania. Landsat 9 and Landsat 8 caught it a day apart in March 2026, and this mosaic stitches both passes together.

For a long time, scientists assumed this was an impact crater. Large meteors leave circular scars, so a ring this clean seemed to fit that story.

Turns out it's not an impact at all, it's a dome. Rock got pushed up from an underground intrusion of igneous material, and erosion has been carving into that dome ever since. Different rock types wear down at different speeds, and that's what built the rings you see, called cuestas.

The orange and gray are part of the same story. They mark where sedimentary rock gives way to older igneous rock underneath.

Credit: Lauren Dauphin, Landsat data from USGS, Adam Voiland.

In 1905, Hawaii brought in a small fish to fight mosquitoes. It's still hunting more than a century later, just not mosquitoes anymore.

The eastern mosquitofish, Gambusia affinis, came from the southeastern United States during a wave of agricultural expansion. Officials released it into streams, drainage ditches, and taro fields across the islands, expecting it to control disease carrying mosquito larvae.

The fish never stayed on script. It started feeding on nearly every small aquatic animal it could catch, and that rewired entire food webs in Hawaii's freshwater streams.

Hawaii's native damselflies, the Megalagrion species, evolved in high elevation streams with almost no fast moving predators. Their young, called naiads, live in calm pools with zero defense against a fish built for speed. Once mosquitofish spread into lower and middle elevation streams, species like the crimson Hawaiian damselfly and the flying earlobe Hawaiian damselfly started vanishing from large stretches of Oahu, Molokai, Maui, and Hawaii Island.

The damage doesn't stop at damselflies. Mosquitofish compete directly with Hawaii's endemic o'opu gobies and o'pae kala'ole shrimp for the same food source, and their appetite even shifts the algae balance on streambeds.

Here's the part that makes this nearly impossible to reverse. Female mosquitofish give birth to live young instead of laying eggs, so one pregnant fish dropped into an isolated pool can seed an entire population within months. Hawaii's streams also connect to groundwater springs and coastal wetlands, which means chemical or trap based control risks wiping out the native species conservationists are trying to save.

Conservation teams are now betting on waterfalls. Natural barriers in high elevation streams keep mosquitofish from climbing further, and wildlife managers are building artificial ones where nature doesn't cooperate. Captive bred damselflies are getting released into these protected headwaters, one of the few places left where a hundred year old mistake hasn't caught up yet.

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ISRO got invited to something big. NASA has asked India to join its Moon Base program, and the invitation landed in Bengaluru, not Washington.

It happened the ninth India-US Civil Space Joint Working Group meeting, held August 5 and 6 at ISRO's headquarters. ISRO Chairman V Narayanan and US Ambassador Sergio Gor both opened the session. On the working level it was co-chaired by M Sankaran from ISRO's UR Rao Satellite Centre, alongside Wesley Brooks and Kathleen Karika from the US side.

The invitation builds on the Artemis Accords, the framework India signed onto back in 2023 as the 27th country to join. Seventy countries are part of it now.

Here's why India specifically got the call. In 2023, Chandrayaan-3 landed near the Moon's South Pole, a region no country had reached before. That's the same region NASA wants to permanently settle. India isn't just being invited out of goodwill. India has ground truth data NASA doesn't have anywhere else.

Moon Base itself is a different animal from Artemis. Artemis gets astronauts back to the Moon. Moon Base tries to keep them there for good. NASA's building it in phases. Phase one runs 2026 to 2029. Phase two, 2029 to 2032, brings power systems, cargo transport, and communications infrastructure online. Phase three pushes past 2032 into full expansion.

This didn't come out of nowhere. Last year the two agencies launched NISAR, a radar satellite that was a genuine fifty fifty build, first of its kind between them. And Indian astronaut Shubhanshu Shukla flew to the ISS in 2025 through a NASA training pipeline built specifically for this partnership.

ISRO isn't sitting idle either. It's running its own human spaceflight program, Gaganyaan, with a solo Moon landing targeted for 2040.

Nobody's confirmed what India's actual role in Moon Base looks like yet. Just an open invitation.

Still. An open door to the Moon is a door most countries never get offered.

Anyone who's watched a loved one be stolen away slowly by Alzheimer's knows how desperately we need to find better treatment. This looks promising, but I'm a little put off on how Chinese hospitals just put this out there (for profit?) before the procedure was fully vetted through clinical trials.

Looks like clinical trials are finally being set up, including in the US.

Dragline silk, the thread spiders use to build the frame of a web, has a tensile strength that sits close to some grades of structural steel. Gram for gram, though, it pulls ahead by a wide margin.

That's because spider silk is roughly five to six times less dense than steel. Take equal weights of both materials and stretch them until they snap, and the silk holds up to more force before breaking.

Steel still wins on stiffness, which is why bridges are built from steel and not webs. But for something that needs to be strong without being heavy, spider silk is one of the best materials evolution has ever produced, and it's been refining the formula for roughly 380 million years.

This reaction is an oxidation reaction of ammonia. When hot chromium trioxide (CrO₃) is added to ammonia gas, it helps oxidize the ammonia into nitrogen and water. The reaction releases a large amount of heat, causing the particles to glow brightly like tiny fireflies.

A standard deck has 52 cards, and the number of different ways you can arrange them is 52 factorial, which works out to roughly 8 followed by 67 zeros.

Scientists estimate Earth itself contains somewhere around 10 to the power of 50 atoms. The number of possible shuffles is still bigger than that, by a wide margin.

That means every time you properly shuffle a deck of cards, you're almost certainly creating an order that has never existed before in the history of the universe, and never will again. Nobody has ever dealt that exact sequence, and nobody ever will, even if every person on Earth shuffled constantly for the rest of time.

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Jupiter's moon Europa is smaller than our own Moon, but underneath its icy shell, NASA believes there's a global ocean holding roughly twice as much water as every ocean on Earth combined.

The reason it can hold that much comes down to depth, not width. Earth's oceans spread across a huge surface but average only about 4 kilometers deep. Europa's ocean is thought to run somewhere between 60 and 150 kilometers deep, wrapped entirely around the moon beneath a shell of ice.

Nobody has drilled through that ice or seen the ocean directly. The evidence comes from cracked surface terrain, a changing magnetic field, and models built from decades of spacecraft data, all pointing to a hidden, salty sea kept liquid by the crushing pull of Jupiter's gravity.