Astrobiology Log · University of Pennsylvania · 2026

Is Planet Pe Kabhi Sunrise Ya Sunset Nahi Hota — Phir Bhi Life Possible Hai?

Ek taraf hamesha jalta hua din, doosri taraf hamesha jamti hui raat — phir bhi scientists kehte hain life ke liye ummeed baaki hai. 🌗🔬

LHS 3844b — Earth se thoda bada ek exoplanet, jo apne red dwarf star LHS 3884 ke around orbit karta hai, humse 48.5 light years door. Earth ke ulat, yeh tidally locked hai — matlab yeh apni axis pe utni hi der mein ek chakkar poora karta hai jitni der mein apne star ke around ek orbit poora karta hai. Result? Ek hemisphere hamesha blistering daylight mein rehta hai, doosra hamesha itni thandi darkness mein doob jaata hai ki almost absolute zero (zero Kelvin) tak pahunch jaata hai.

Pehli nazar mein, yeh environment completely inhospitable lagta hai. Day-side temperature roughly 1,000 se 2,000 Kelvin tak pahunch sakta hai, jabki night-side itna cold hota hai ki particle motion effectively ruk jaata hai. Lekin naye research ne suggest kiya hai ki yeh worlds itne hostile nahi hain jitne dikhte hain.

💭 Daisuke Noto Ka Nazariya

Daisuke Noto (University of Pennsylvania ke Penn GEFLOW Lab mein postdoctoral researcher) ke mutabik, sirf day-side aur night-side ke extreme temperatures dekh kar — 1,000-2,000 Kelvin garmi aur almost absolute zero thand — lag sakta hai ki yeh exoplanets life ke liye bahut hi harsh hain. Lekin unke mutabik, life shayad phir bhi apna raasta dhoondh le.

Nature Communications journal mein publish hui is study mein, Noto aur unke collaborators (Japan Agency for Marine-Earth Science and Technology aur Hokkaido University se) ne paaya ki aise exoplanets life sustain karne ke liye zyada tolerant ho sakte hain — kyunki tidal locking heat flux ko laterally distribute karke locally moderate thermal environments maintain karne mein contribute kar sakti hai.

🌙 Tidally Locked Planets Itne Common Kyun Hain?

Yeh findings ek common assumption ko challenge karti hain. Noto ke mutabik, permanent day aur night wale worlds actually Earth jaise regular day-night cycle wale planets se zyada common hain.

Woh explain karte hain ki moons aur planets jo apne parent stars ke bahut kareeb hote hain, unhe hum "tidally locked" kehte hain — matlab jab woh apni axis pe spin karte hain aur apne parent ke around orbit karte hain, dono rates match ho jaate hain. Isi phenomenon ki wajah se hum hamesha apne Moon ka sirf ek hi side dekh paate hain!

Yeh constant orientation planet ke across ek dramatic temperature contrast create karta hai. Surface conditions pe hi focus karne ke bajaye, researchers yeh samajhna chahte the ki planet ke andar — specifically mantle mein (crust aur core ke beech ki thick rocky layer) — kya ho raha hai.

Mantle ke andar heat ek continuous loop mein circulate karta hai.

🧪 Lab Mein Ek Alien Planet Recreate Karna

Sirf computer simulations pe depend karne ke bajaye, team ne ek tidally locked planet ke interior ko mimic karne ke liye ek physical laboratory model banaya.

"Building an actual exoplanet in the lab wasn't in the budget," Noto jokes.

— Daisuke Noto, University of Pennsylvania

Iske bajaye, researchers ne ek tabletop rectangular tank use kiya, jo viscous glycerol aur tiny thermochromic liquid crystals se bhara tha — yeh crystals temperature shift hone par color badalte hain. Aise experimental systems pehle bhi study karne ke liye use hote aaye hain ki heat slow-moving materials ke through kaise move karta hai, isliye yeh rocky planetary interiors ke liye achhe stand-ins hain.

Earth ki rotation aur gravity se strongly influenced weather ya ocean currents ke ulat, rocky mantle ke andar convection mainly temperature aur density ke differences se driven hota hai. Un conditions ko reproduce karne ke liye, team ne tank ke around 4 thermostats install kiye — alag-alag regions ko heat aur cool karne ke liye, taaki permanently lit side, permanently dark side, surface, aur deep interior ke beech jaise temperature gradients expected hain, waise hi create ho sakein.

💓 Ek Planetary Heat Engine

Experiments ne ek remarkably stable pattern reveal kiya. Hot material consistently day-side ke neeche se upar uthta, upper region ke across flow karta, night-side pahunch kar cool hota, phir sink hokar lower mantle ke through wapas laut aata. Result ek continuous circulation loop tha, jo ek steady "planetary heartbeat" ki tarah behave karta.

Yeh pattern Earth ke mantle jitna chaotic nahi hai — balki slow, steady, aur predictable hai, jo apne aap mein ek boring-but-reassuring cheez hai.

Researchers ne occasionally mushroom-shaped plumes bhi observe kiye jo tank ke heated base se rise ho rahe the. Hawaii ya Iceland jaisi Earth ke volcanic hotspots ke ulat (jo time ke saath drift karte hain), yeh plumes ek hi location pe fixed rahe.

Heat transport ki measurements (jinhe Nusselt numbers kaha jaata hai) Earth ke mantle ke jaisi hi comparable payi gayi. Yeh finding suggest karti hai ki kuch tidally locked exoplanets localized geothermal environments maintain kar sakte hain — jo especially mid-latitudes mein life ke favor mein conditions provide kar sakte hain.

🧲 Alien Life Ke Liye Iska Kya Matlab Ho Sakta Hai?

Yeh steady circulation pattern sirf surface temperatures se zyada cheezon ko influence kar sakta hai. Noto ke mutabik, yeh planet ke liquid core ke movement ko bhi affect kar sakta hai — potentially aise magnetic fields generate karte hue jo Earth ke familiar dipole field se different hon. Yeh idea abhi is experiment mein test nahi hui, lekin future work ke liye ek exciting direction hai.

48.5 ly

Distance from our Solar System

1,000–2,000K

Day-side surface temperature

~0K

Night-side temperature (near absolute zero)

🔮 Aage Kya?

Noto aur unke supervisor Hugo Ulloa (Penn Arts & Sciences ke Earth and Environmental Science department mein assistant professor) similar laboratory models develop karna continue kar rahe hain, taaki geophysical processes ki ek wide range explore ki ja sake. Penn GEFLOW Lab ki earlier research ne yeh explore kiya tha ki heat aur mass confined spaces ke through kaise move karte hain — hydrothermal systems mein fluids ke role ke baare mein naye insights dete hue.

Team ka plan hai in experimental methods ko aur extend karna, apne planet ke different systems ko different contexts mein deeper samajhne ke liye — kyunki possibilities, quite literally, is duniya se bahar hain.

"Na sunrise, na sunset — phir bhi ek planet ke andar dheere-dheere dhadakta hua ek heartbeat life ke liye jagah bana sakta hai." 🌗💓

Source: University of Pennsylvania, July 2026 · Noto, D. et al., "Convective dynamics in mantle of tidally-locked exoplanets," Nature Communications, 2025; 16(1) · DOI: 10.1038/s41467-025-62026-z