All articles tagged with #microgravity
A University of Copenhagen and NASA study found that microgravity slows intestinal movement, causing gut bacteria to ferment protein instead of fiber. This shift, detected in blood samples from 52 ISS astronauts, explains common space constipation and poses risks for long-duration missions to Mars.
Researchers at New York University have demonstrated that human cells maintain stable genome organization after 24 hours in simulated microgravity, challenging previous assumptions about immediate genetic damage in space. By using a custom random-positioning machine that minimizes fluid currents, the team isolated the effects of gravity from mechanical stress, finding no detectable DNA damage or disruption to the nuclear envelope. While the nucleus expanded and the nucleolus smoothed, these changes were distinct from the DNA damage caused by fluid flow in traditional rotating cultures. This finding supports the emerging concept of treating gravity as a variable 'dose' for health, though experts caution that long-duration spaceflight involves additional factors like radiation that this short-term experiment did not replicate.
NASA astronaut Jessica Meir shares her zero-G curly-hair routine aboard the ISS: she uses no-rinse shampoo focusing on the scalp, rinses with a water pouch, dries with a dedicated T-shirt, avoids brushes to reduce frizz, and applies leave-in conditioner; humidity isn’t a major issue in microgravity, and she notes Earthly 3a curls become more like 3c in space, with a real shower back on Earth anticipated.
NASA grew Hatch chile peppers on the International Space Station for 137 days in the Advanced Plant Habitat, yielding 26 peppers from four plants; in microgravity the pedicels connecting flowers to fruit grew straight, a clear morphological effect of weightlessness. The crop was partly eaten on orbit and partly frozen for return, Earth controls showed about a two-week growth lag, and microbial analysis found low counts with no pathogens, supporting space farming viability and guiding future crops like tomatoes and leafy greens.
NASA’s PH-04 experiment on the International Space Station grew Hatch chile peppers in microgravity, yielding 26 peppers from four plants over 137 days. In space, the pedicels connecting flowers and fruit were completely straight, a clear microgravity effect, and pepper development lagged about two weeks versus Earth. Pollination was aided by airflow and hand-pollination; astronauts harvested peppers for meals—even calling one harvest “space tacos”—demonstrating that fruiting crops can be grown in orbit and informing future space farming for Moon and Mars missions.
NASA’s space germination tests with corn show that microgravity erases the plant’s directional cue, causing roots and shoots to grow in tangled patterns even as tissue remains healthy; scientists caution the five-day snapshot and connect findings to similar orientation issues in Arabidopsis and gene-expression studies, informing future space farming designs and the Open Science Data Repository that supports long-duration missions to Mars.
A NASA-backed Nature Communications study analyzed more than 400 blood samples from 52 astronauts who stayed on the International Space Station for 2+ months (2006–2018) and found microgravity slows gut movement and shifts gut bacteria to ferment protein more than usual, helping explain space constipation. While dietary changes (caffeine, fish, fat) influence metabolites, microgravity is the main driver; the resulting protein‑fermentation byproducts may be linked to kidney stress, mood changes, and gut inflammation—risks that could grow on longer missions to Mars. Researchers suggest countermeasures like higher‑fiber diets, probiotics, or ways to boost peristalsis, noting the findings could also illuminate bed‑rest effects on Earth.
A study of 488 plasma samples from 52 astronauts on the ISS shows microgravity slows food transit through the gut, prompting gut bacteria to ferment proteins more than usual and producing metabolites that enter the bloodstream. The effect starts within weeks in space and largely reverses after returning to Earth. Findings suggest dietary fiber or slowly fermented carbohydrates could counteract the change for long-duration missions and also offer insights into Earth-based digestive health; published in Nature Communications.
An npj Microgravity study finds that in near-zero gravity boiling liquid nitrogen can temporarily improve heat removal because bubbles cling to the heater, but once a heat threshold is exceeded cooling collapses (max heat removal falls ~65% vs ground tests); the result emphasizes surface design, using a smooth silicon wafer, for cooling space fuels and electronics.
In near-zero gravity, boiling of cryogenic liquids like liquid nitrogen can transfer heat more effectively because bubbles linger on heated surfaces, improving cooling—up to a point. Parabolic-flight experiments show reduced gravity enhances heat removal initially, but the cooling limit is reached quickly as bubbles link and dry the surface, collapsing the system. Findings underscore the importance of surface design for space cooling and propellant storage, though tests were limited to nitrogen and short flights.
Spaceflight shifts body fluids toward the head and dulls taste/smell, making eating and drinking in orbit less satisfying and potentially reducing food intake. Swallowing itself doesn’t require gravity, but microgravity alters saliva production and oral conditions, contributing to dry mouth and swallowing difficulties. These changes can affect nutrition and hydration on long missions, such as a Mars voyage, prompting research into texture-modified foods and 3D-printed meals to tailor nutrition and ease swallowing for astronauts.
Months in space trigger a headward fluid shift that makes astronauts look puffy, while bones lose mineral, muscles shrink (calf ~15%), and the heart becomes smaller with less work to do; the spine lengthens in orbit and briefly grows taller, then returns after landing. Eye changes linked to spaceflight-associated neuro-ocular syndrome raise vision concerns on long missions. NASA’s Twin Study showed most changes reverse on return, but about 7% of gene activity remained altered for months and some cognitive and vascular changes persisted. Exercise and nutrition blunt these effects but don’t fully prevent them, underscoring the need for better countermeasures—possibly artificial gravity—for future multi-year missions to Mars.
In microgravity, the spine can lengthen by up to about five centimetres, leaving astronauts temporarily taller on return to Earth before gravity compresses the spine within days; the height gain is attributed to loading changes from gravity rather than muscle or bone loss. Historical data from Apollo-Soyuz and Skylab, plus ISS studies, support this, with seated height measurements affecting helmet and suit fit. The article also notes post-flight back injury risk and calls for routine in-flight measurements, post-flight imaging, and exploration of lumbar-focused countermeasures, given implications for future Artemis/Mars-class missions.
Astronauts on the International Space Station grew a potassium chloride crystal in microgravity that formed a hollow, scroll-like pyramid shape due to hopper growth—edges and corners extend faster than the faces when gravity is minimal. This gravity-free growth yields unusually orderly structures and fewer defects, offering insight into ideal crystal formation that could inform Earth-made semiconductors and other advanced materials.
Astronauts on the ISS grew potassium chloride crystals in microgravity, producing hollow, stair-step “hopper” pyramids as edges and corners expand faster than faces. The near-weightless environment prevents gravity from pulling the crystal down, enabling unusually regular, low-defect structures that could inform earthly materials manufacturing and semiconductor tech—demonstrating how microgravity changes crystallization and sparking scientific curiosity.