NASA is calling for student tech ideas! 6th-12th grade educators & students affiliated with U.S. schools are invited to enter the NASA TechRise Student Challenge. Winning teams receive funds to build an experiment and a spot on a NASA-sponsored test flight: https://www.futureengineers.org/nasatechrise

We’ve discovered more than 6,000 planets orbiting other stars, but we haven’t found another Earth.

Astrophysicist Erika Hamden explains that finding a planet is very different from finding a place we could survive. Some have no solid surface to stand on. Others are too hot or too cold and even a rocky planet could have an atmosphere we can’t breathe. For now, Earth is the only home we know.

This project is part of IF/THEN®, an initiative of Lyda Hill Philanthropies.

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.

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.

Here's the link to the special: https://www.youtube.com/watch?v=72IwnxnejfE

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!

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 if you could eat your water bottle instead of recycling it? 💧

Alex Dainis shows how, using a bit of kitchen chemistry. Sodium alginate, a powder derived from seaweed, reacts with calcium lactate to form a gel wherever the two meet. Mix a diluted alginate solution (colored so you can watch the reaction) and drop it into a calcium lactate solution with a deep spoon; the alginate polymerizes instantly at the boundary between the two liquids, sealing a pocket of water inside. The result is a squishy, science-powered "water balloon" that tastes just like water.

Can physics create art? 🎨

Greg Wolf explains how this pendulum swings along two perpendicular axes, each with its own natural frequency, and the relationship between them determines what pattern emerges. When those frequencies fall into a simple ratio, the sand traces a clean geometric pattern called a Lissajous figure; without a repeating relationship, the pattern breaks down into something irregular and chaotic. It looks like a bottle of sand swinging through the air, but it's really two harmonic motions interacting to turn physics into art.

Most people's morning starts with a cup of coffee. Ours started with a cup of coffee under a microscope. ☕🔬

Our friend Chloé Savard, also known as tardibabe on Instagram, zoomed in and found a whole universe brewing in there. Those first jagged brown shards are just the roasted grounds, tiny fragments of a plant cell wall, packed with the oils and pigments produced during roasting. That deep color and smell come courtesy of the Maillard reaction, a chemical exchange between sugars and amino acids.

Roasting traps carbon dioxide inside the bean, so the moment water hits the grounds, that gas comes rushing out, a process baristas call degassing. Some of those coffee bubbles get a natural assist from the coffee's own oils, which act as a surfactant and let them hold their shape long enough for us actually to see them.

The shimmer on those coffee bubbles is a thin-film interference, the same physics that makes soap bubbles rainbow-colored. Light bounces off both the outside and inside of the paper-thin bubble wall, and those two reflections overlap and cancel each other out in different ways depending on the wall's thickness. That's why the color shifts as you look across a single bubble.

Lastly, those gold flecks drifting through the coffee? Just suspended coffee oil and fine particulates, catching the light like sediment in a snow globe.

All of that, quietly happening, in the ten minutes it takes most of us to drink it.

What happens if you put a carrot in the microwave? 🥕💥

Alex Dainis demonstrates how metals in the microwave are dangerous, even the smaller ones in root vegetables like carrots! Iron, potassium, and copper are nutrients from the soil that plants need to grow, and they can store those metals in the roots of vegetables. These points in the carrots can act as a focal point in the microwave, creating an increase in the electrical field, and even sparks!

You can’t see it, but there’s a polymer coating inside your aluminum can. 🥫

Chemteacherphil uses chemistry to prove it! Working with lye, which is highly caustic and requires proper safety equipment (so please don't try this one at home), he makes a solution that reacts with the aluminum, converting it into a compound that dissolves in water. When the aluminum is gone, you can see the polymer coating! These coatings are useful because without them, acidic drinks could slowly corrode the aluminum underneath.

Can you design and build a rocket launcher using just a few simple supplies? 🚀

Greg Wolf says yes, using PVC, cable ties, a two-liter bottle filled about a third with water, a bicycle pump and a tire valve for pressurization. It all comes down to Newton's third law: for every action, there's an equal and opposite reaction. Compressed air pushes down on the water inside the bottle, and when released, that pressure forces the water out at high speed, launching the rocket skyward.

You can make a tower of hot ice with ingredients in your home! 🧊🔥

Alex Dainis shows us how with sodium acetate, which you can make using baking soda and vinegar. To get the tower effect, you’ll mix these ingredients together over heat with water, and then set them in a refrigerator to cool. Once cooled, you can slowly pour them out onto your surface, and it will crystalize into your tower!

Our friend Chloé Savard, also known as tardibabe on Instagram, shows us how volvox are a genus of multicellular freshwater free-swimming green algae. The larger spheres are colonies of small biflagellate cells with smaller aflagellate round colonies inside which are the daughter colonies, or the baby algae. 

The biflagellated cells are responsible for locomotion and spinning movements toward a light source so they can produce sugar by photosynthesis, just as plants! Those biflagellated cells also possess an eyespot which is responsible for detecting light and guide the colony towards optimal light conditions. The flagellated cells that compose the large mother colony are all interconnected by small cytoplasmic bridges that can help connect neighboring cells and, in some Volvox species, transport nutrients

Within the volvox colony is an ostracod, a crustacean just like crabs, lobsters and shrimp! They possess a two part shell that closes just like mussels and oysters, but they aren’t mollusks like these guys though. Their bivalved carapaces are largely made of low-magnesium calcite which is secreted by these small crustaceans. Many are around a millimeter long, making some large enough to see with the naked eye.

A volvox colony is typically formed from two types of cells; germ and somatic. The larger sphere is composed of thousands of somatic cells responsible for photosynthesis and motility. These cells create a water flow around the colony, but they cannot divide and are programmed to die within a few days. Germ cells are nonmotile, but can divide asexually and form new little daughter colonies. These generative cells are basically responsible for Volvox’s growth and reproduction and are considered potentially immortal because they give rise to future generations. When the mother colony breaks open, the young colonies can escape and start their life!

Tiny organisms, incredibly complex lives, and a whole world we’d never see without a microscope.

References:

• Caporaletti, Marco. “Ostracods and Stable Isotopes: Proxies for Palaeoenvironmental Reconstructions.” Joannea Geologie und Paläontologie, vol. 11, 2011, pp. 345–359.
• Domozych, David S., and Catherine E. Domozych. “Multicellularity in Green Algae: Upsizing in a Walled Complex.” Frontiers in Plant Science, vol. 5, 2014, article 649. doi:10.3389/fpls.2014.00649.
• Harada, Keigo, et al. “Position-Dependent Roles of Somatic Cells in Phototaxis of Volvox.” PNAS Nexus, vol. 3, no. 10, 2024, article pgae444. doi:10.1093/pnasnexus/pgae444.
• Hoops, Harold J., Ichiro Nishii, and David L. Kirk. “Cytoplasmic Bridges in Volvox and Its Relatives.” Madame Curie Bioscience Database, Landes Bioscience, 2000–2013.
• Kirk, David L. “The Genetic Program for Germ-Soma Differentiation in Volvox.” Annual Review of Genetics, vol. 31, 1997, pp. 359–380. doi:10.1146/annurev.genet.31.1.359.
• Umen, James G. “Volvox and Volvocine Green Algae.” EvoDevo, vol. 11, 2020, article 13. doi:10.1186/s13227-020-00158-7.

HLA365, a study app for the CHS exam (ASHI's Certified Histocompatibility Specialist cert) and EFI accreditation exams. Sharing it here in case it's useful to anyone on this sub studying the specialty or who want a handy review tool.

What's in it:

• 39 topics covering the full CHS blueprint — immunology fundamentals, HLA nomenclature, molecular typing (PCR-SSP/SSO/SBT/NGS), serology and crossmatch testing, antibody detection, KIR genotyping, solid organ and stem cell transplant, population genetics, lab regulatory topics
• Topic quizzes (15 questions each) with three levels of explanation per answer — quick summary, technical breakdown, and key recall points
• Full-length randomized practice exams pulled from 1,000+ questions, with post-exam review of everything missed
• Flashcard review library for quick refreshers
• Works fully offline — everything's bundled in the app, nothing uploaded, no account required

Free to try for 3 days, then a one-time $25 purchase unlocks it permanently — no subscription. Now live Only on Google Play!

Link: https://play.google.com/store/apps/details?id=com.hla365.examprep

Why does some glass not hurt when it shatters? 🥽💥

Phil Cook, also known on YouTube as chemteacherphil, demonstrates how sugar can be turned into real life "breakaway glass." Don’t try this at home, although it is not real glass, it can still be dangerous! When you heat sugar and water to 300 °F it reaches the hard crack stage. When the liquid cools the molecules get locked into a disordered structure, forming an amorphous solid, just like real glass, minus the razor sharp shards. It's the same trick behind those Hollywood stunt bottles, made from sugar instead of a brittle plastic resin.

Did you know you’re sharing your bed with thousands of tiny arachnids? 🧹 

Quinten Geldhof, also known as Microhobbyist, introduces us to the household dust mite. Related to ticks and spiders, they feed on skin flakes, fabric fibers, and dirt particles and are only visible under a microscope. People with dust allergies are actually allergic to the waste these tiny critters produce, not the dust itself!