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Why NASA Chose Mars Instead of Venus

Why NASA Chose Mars Instead of Venus ❤ If you'd like to support the channel -    / @boringsciencetosleep   Venus is closer to Earth than Mars. It's roughly the same size as our planet. Launch windows open more frequently. Flight time is shorter. Yet every space agency that's ever existed has chosen Mars instead. That seems backwards, doesn't it? We've sent three rovers to Mars that are still driving around right now. We're planning human missions. SpaceX wants to build a city there. Meanwhile, Venus gets maybe one mission per decade, and those spacecraft die within hours of arrival. The last time NASA sent anything to Venus was 1989. There's a reason for this choice that goes deeper than you think. It's not just about distance or difficulty. It's about something fundamental that determines which worlds humans can actually explore and which ones will remain forever out of reach. Let me show you what's really happening here. Start with the obvious problem. Venus has a surface temperature of 464 degrees Celsius. That's hot enough to melt lead. The atmospheric pressure down there is 93 bars—equivalent to being 900 meters underwater on Earth. The air itself is 96.5% carbon dioxide, and the clouds are made of sulfuric acid. When the Soviet Union landed their Venera probes on Venus in the 1970s and 80s, those spacecraft survived for maybe two hours before the environment destroyed them completely. They managed to send back a handful of grainy photos showing a rocky, desolate landscape, then went silent forever. Compare that to Mars. Surface temperatures range from -133°C at the winter pole to a relatively balmy 27°C during summer. The average sits around -55°C. Cold, yes, but not impossible. The atmospheric pressure is less than 0.01 bar—basically a vacuum—but that creates different problems than crushing pressure. Problems we can engineer around. The Spirit rover landed on Mars in 2004 with a planned mission duration of 90 days. It operated for six years, driving over 7.73 kilometers and sending back thousands of images. The Opportunity rover, Spirit's twin, was supposed to last 90 days as well. It survived for fifteen years. You can't do that on Venus. The environment simply won't allow it. But here's what makes this interesting. Venus wasn't always this way. About four billion years ago, Venus might have looked remarkably similar to early Earth. Scientists speculate it had liquid water on its surface. Possibly oceans. The atmospheric pressure and temperature were likely far more moderate. Venus, Earth, and Mars all started with roughly the same ingredients—similar distances from the Sun, similar compositions, similar potential for habitability. Then something catastrophic happened on Venus. The leading theory involves a runaway greenhouse effect. Venus's proximity to the Sun meant slightly more solar radiation hitting its surface. That extra heat caused more water to evaporate from the oceans. Water vapor is a greenhouse gas, so it trapped more heat, which caused more evaporation, which trapped more heat. The cycle accelerated until every drop of water had boiled away into the atmosphere. Then the water molecules broke apart from intense ultraviolet radiation. Hydrogen escaped to space. What remained was an atmosphere of almost pure carbon dioxide with clouds of sulfuric acid, creating the hellscape we observe today. 🌌 Thanks for watching you Amazing People! 💤 I really hope this documentary helped you to relax or simply calm your restless mind, do let me know below... I’d also love to know, ✅ How’s your day going, and how’s life treating you? – If you learned anything new? 🤔 – What was your favorite part/section in the video? 🧠 -- Did you finish the documentary or watch the video till the end? – And where in the world are you listening from? 🌎 ✨ Subscribe for more calmly narrated science journeys through time, space and the history of the Universe:    / @boringsciencetosleep   #space #documentary #science #calmvideo