u/TheMuseumOfScience

Your brain may have once been two separate organs! 🧠

Scientists long thought the whole brain grew from a single group of embryonic cells. But a new study of mouse embryos found it actually develops from two, one forming the forebrain and the other the hindbrain. Similar trends in chickens and zebrafish suggest that over 500 million years ago, evolution may have brought two separate nervous systems together to form the brain.

What does AI see when it looks at the stars? 🤖🔭🧪

Theoretical cosmologist Paul Sutter explores how AI tools can co-discover with scientists and take part in the scientific process. A large language model can process the same telescope data we do, from images of Saturn’s rings to a live telescope feed, but what happens between input and output remains a mystery. Asking what AI sees is really asking about our own relationship with the wider universe.

Does cutting the moldy spot off your food make it safe? 🍞 

Quinten Geldhof, also known as Microhobbyist, takes us under the microscope to reveal thread-like roots called hyphae spreading through food far beyond the visible surface. These roots penetrate soft foods like bread and fruit with ease, while hard cheeses and vegetables are more resistant. These molds can contain mycotoxins, poisonous compounds that are hazardous to your health. Would you eat moldy food?

Is this candle haunted? 🕯️👻

Alex Dainis places two candles on a lazy Susan with a piece of glass in between, and when the closer candle is lit, its flame appears to jump to the other one. Most light passes through the glass, but some of the light from the close candle bounces back at us, creating a reflection that makes the flame seem to appear on the far candle. This optical illusion is similar to Pepper's Ghost!

Did you know slime can be a helpful cleaning tool? 🫟

Greg Wolf tweaks the classic glue and borax recipe to make slime tacky enough to grab dirt but clean enough to pull away. The chemistry: borate ions cross-link glue's long polymer chains, turning runny glue into slime. Less activator makes it stretchy like the toy, while just enough makes it a surprisingly satisfying debris grabber.

How do tree frogs' feet stick? 🐸

Their feet don’t have suction cups! Instead, glands in their toes expel mucus through narrow grooves between the tiny hexagonal cells on their toe pads. This mucus has adhesive and cohesive properties, letting the tree frog stick to surfaces in a process called wet adhesion. This adaptation helps tree frogs defy gravity, even on wet tree leaves or bark.

Can removing a dam fix an ecosystem? 🌊

Habitat fragmentation is a major driver of biodiversity decline because split habitats make it harder for animals to move, survive, and reproduce. After the Klamath River's last four dams came down in 2024, researchers used sonar and video to count an estimated 7,742 adult Chinook salmon past the former Iron Gate Dam site, and that number jumped to over 13,300 in 2025. Scientists also documented active spawning in newly accessible habitat and juvenile Chinook using tributaries cut off for over a century.

Did Perseverance find evidence of past life on Mars last year? 🦠

The rover discovered very specific minerals on the rim of a Martian crater. On Earth, those minerals are biosignatures, or evidence of life. We can't say for sure it's a Mars biosignature, because non-biological processes can make these minerals too. However, those processes leave other evidence in the rocks that we're not seeing. That means our best explanation right now is past Martian biology.

Did you know you can turn a leaf into a working boat with dish soap? 🍃🚢

Alex Dainis shows how it works! Dish soap contains ingredients called "surfactants" that lower the surface tension of water, which is what helps oil and water mix to wash away grease. On the leaf, the soap lowers the tension only at the back, and that difference between front and back pushes the leaf forward!

Is intelligent life harder to make than regular life? 🌱

Theoretical cosmologist Paul Sutter points to our one data point, Earth, where life appeared basically as soon as the planet cooled down, and maybe even a little before. Then it took 4 billion years for intelligent life to show up. So if we find evidence of life on another planet, it's probably going to be bacteria, or alien bacteria.

Can sea squirts help reverse aging? 🪸

Sea squirts are filter feeders that are edible ascidians! They are a source of “plasmalogens”, a lipid found in our cell membranes that supports brain and heart health. After studying the effects of eating sea squirts on mice, scientists found that it may lower brain inflammation and help memory! With more research, we could discover if eating plasmalogen could help reverse aging in humans.

The moon has a new once-in-a-century crater! 🌕

McGetchin crater is the largest new crater ever seen anywhere in the solar system, stretching almost 730 feet wide and 140 feet deep after an asteroid or comet the size of a 3-6 story building smacked into the lunar surface between April and May of 2024. Impacts this big are estimated to happen only about every 130 years, making this fresh crater a rare chance to study one up close with spacecraft like the Lunar Reconnaissance Orbiter.

Can life exist without a moon? 🌕

Theoretical cosmologist Paul Sutter explains how we are still answering this question. The moon protects the Earth in multiple ways, from blocking hits and forming craters as a result, to balancing out our weather with the axial tilt. To find the answer, scientists are now looking for planets with exomoons to study more!

Meteors are about to enter our atmosphere at 41 miles per second! 🌠

Born from the debris of Halley's Comet, the Orionids light up the sky from October 2 to November 7, peaking overnight October 21 to 22. Catch around 20 meteors per hour at the peak, with standout years reaching up to 75. Skywatchers in both hemispheres can join in, so head somewhere dark before dawn, let your eyes adjust, and look up!

Every time you swim in a mountain lake, you're sharing the water with thousands of microbes you never see. 🔬

Our friend Chloé Savard, also known as tardibabe on Instagram, took a closer look, and it turns out that alpine water is packed with desmids, ciliates, and water fleas, all going about their business at a scale most of us never think to look at.

The stars of the show are Micrasterias, a genus of desmid, single-celled green algae built like tiny symmetrical snowflakes. Each cell is split into two mirror-image halves called semicells, connected at a narrow waist. When a Micrasterias divides, each half grows a brand new matching semicell to replace the one it left behind.

Alongside them is a Closterium, another desmid, but elongated and curved like a crescent moon. Closterium cells often carry visible crystals of barium sulfate inside vacuoles at each end, structures thought to help the cell sense gravity and orient itself in the water.

Then there's the ciliate glowing with yellow-green flecks scattered through its body, that's zoochlorellae, symbiotic algae living inside a single cell, a partnership where the algae photosynthesize and share sugars with their host in exchange for shelter.

And weaving through nearly every frame are the Chydoridae, a family of tiny water fleas that prefer to live and forage along the benthic zone, the bottom layer of ponds and lakes, rather than out in open water. Look closely and you can catch one carrying a cluster of eggs along for the ride.

Next time you swim in a mountain lake, remember: you were never really swimming alone.

References: 

• Brook, A. J., Fotheringham, A., Bradly, J., & Jenkins, A. (1980). Barium accumulation by desmids of the genus Closterium (Zygnemaphyceae). British Phycological Journal, 15(3), 261–264. https://doi.org/10.1080/00071618000650251
• Esteban, G. F., Fenchel, T., & Finlay, B. J. (2010). Mixotrophy in ciliates. Protist, 161(5), 621–641. https://doi.org/10.1016/j.protis.2010.08.002
• Klemetsen, A., Aase, B. M., & Amundsen, P.-A. (2020). Diversity, abundance, and life histories of littoral chydorids (Cladocera: Chydoridae) in a subarctic European lake. Journal of Crustacean Biology, 40(5), 534–543. https://doi.org/10.1093/jcbiol/ruaa048
• Lutz-Meindl, U. (2016). Micrasterias as a model system in plant cell biology. Frontiers in Plant Science, 7, 999. https://doi.org/10.3389/fpls.2016.00999

Can you make dry erase marker drawings float? ✍️

Alex Dainis demonstrates by drawing on a shiny plate, letting it dry, and adding a squirt of mystery liquid at the edge to lift the whole picture up. Dry erase markers contain pigment for color, a solvent to suspend it, and an oily polymer that keeps the ink from sticking to whiteboards. Once the solvent evaporates, the pigment and polymer form a thin, oily layer that floats right on top of plain old water!

What really happens when a boa squeezes its prey? 🐍

Meet Belize, our boa constrictor! Scientists once believed her species suffocates its prey, but constriction actually cuts off circulation to major organs, triggering cardiac arrest, and boas can even feel the exact moment their prey's pulse stops. Digestion takes four to six days depending on the size of the meal, yet boas are so energy efficient they can go weeks between meals. This behavior is purely a hunting adaptation, not aggression, so despite appearances boas aren't looking for a fight.

If Earth and Venus are so similar, why are they also so different? 🌎🪐

Kyle Horn of MIT AeroAstro explains that the two planets are roughly the same size and occupy neighboring orbits around the Sun. Yet Earth ended up with liquid water and a comparatively temperate climate, while Venus is a hellish 450°C under 90 bar of pressure, hot enough to melt lead. These diverging climates hold clues to how the early solar system formed. Understanding Venus, our closest planetary neighbor, matters even more now. Our current observation techniques are already biased toward spotting "exo-Venuses" rather than "exo-Earths" among distant exoplanets.

Did NASA’s new space observatory just double its own lifetime? 🛰️

The Nancy Grace Roman Space Telescope launched August 30th and is now cruising toward a spot nearly a million miles from Earth, where its leftover fuel will decide exactly how long it can keep pointing at cosmic targets. Engineers once expected around ten years of fuel by the time Roman reached that destination, but its journey out has been so efficient that estimate has jumped to up to 22 years, more than double the original number. That's over two decades of revolutionary astronomy ahead, and honestly, a fantastic day for space nerds everywhere.