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91

Technically, yes, it would be easier to put people on Venus. You need less of a kick for the interplanetary trip and slowing down is trivial with that dense atmosphere...one of the Pioneer Multiprobe sub-probes made a soft landing despite only being designed as atmospheric probes. However, the surface temperature stays close to 464 °C, with over 90 ...


58

The reason is delta-v, which is a crucial concept in Spaceflight. It means change in velocity, and is the primary 'currency' that space mission have to expend in order to reach places in the solar system. On earth, if you want to go anywhere, you can get there at any speed, it just takes longer. Unfortunately, that is not how it works in space, because the ...


55

It takes surprisingly little delta-v to reach Venus for a flyby -- about 3850 m/s from LEO instead of the 3200 m/s or so required to get to the moon -- so while the payload would have to be reduced from the normal Apollo mission, it wouldn't have been impossible. For Apollo 17, if we consider the payload to be the CSM, LM, and LM adapter, the total is 48.6 ...


49

As others have already pointed out, getting humans to Venus would be marginally easier than getting them to Mars. Let's consider survival on Venus in a little more detail though. Although there haven't been any manned missions to either Mars or Venus, there have been unmanned missions to both. So let's consider how long those unmanned missions have survived. ...


47

The teeth served an aerodynamic function. ...metal teeth were added to the periphery of the impact ring in an effort to reduce the spin and oscillation during the descent and prevent the rough landings experienced by the 1978 missions. This is also why the earlier missions didn't have them, they were added in an attempt to mitigate problems experienced on ...


43

When will we send? We already did. In 1985 and 1986 the Soviet Union sent two Vega probes to Venus. Both included a robotic balloon (usually called aerobots). The two balloon aerobots were designed to float at 54 km from the surface, in the most active layer of the Venusian cloud system. The instrument pack had enough battery power for sixty hours of ...


39

Fans work by moving cool air (or other fluid) over a warm surface. If there is no air, like in space, a fan will serve no purpose. Cooling things in space is actually a bit tricky because of this - objects on earth tend to lose most of their heat through conduction or convection, but in the vacuum of space, all you can do is radiate heat, which a fan will ...


37

We didn't know how hostile Venus's surface was, until we had landed there. The atmosphere of Venus makes it easier to land there than Mars. From Wikipedia, we learn: Before radio observations in the 1960s, many believed that Venus contained a lush, Earth-like environment. While there was some concept that Venus was hot, and had a high pressure, the exact ...


33

Why are people so fascinated about Mars and not about Venus at all? The trivial answer - Mars is moderate place. A human could easily get around with a spacesuit, and it is trivial for robots and equipment to exist on Mars. Venus is a swirling hell. The "atmosphere" is a sea of incredibly hot, ultra-boiling, 800+ F° sulfuric acid (!!!) (Indeed, Venus is ...


30

Is such an orbit even possible? TL;DR: If the Sun wasn't around, yes, such an orbit is possible. But since the Sun is around, such an orbit is impossible. About the name of the orbit Quoting from Emily Lakdawalla, who has a bit more gravitas than some random file blogger, What is a geostationary orbit like at Mars? I have to pause here for a brief ...


27

Buoyancy is a big problem. To stay aloft, the average density of the balloon envelope, lifting gas and gondola must be <= the density of the surrounding atmosphere. The pressure inside a balloon must be equal to or slightly greater than the surrounding atmosphere, otherwise the balloon will collapse. If you look at the ideal gas law you'll see that see ...


25

Thanks to @MarkAddler for his search suggestions I've tried to balance length against completeness, and both lost here. However I have included enough material to try to be convincing that RTGs, singe-use storage batteries, and rechargable batteries for higher power events have all been investigated and solutions exist to provide at least the electrical ...


25

The Soviet Union actually deployed balloons on Venus, so I assume they studied them before that. https://en.wikipedia.org/wiki/Vega_program#Balloon


24

There is one area of exploration on Earth that approximates conditions on Venus, namely that of deep oil and gas mining, and a few additional areas of technology, near avionics engines, and even auto engines. The stated goal for such electronics is to function at 200 C or higher. The most promising technology for surviving high temperatures is Silicon ...


23

Based on saturation diving operations, it looks like the limits are as follows: Compressed air: Nitrogen narcosis limits you to around four times Earth's atmospheric pressure. Any gas mix: Hydreliox was used for the current depth record; insomnia and fatigue issues appear to limit you to around 65 times Earth's pressure regardless of gas mix. Neither Titan ...


22

According to Wikipedia launch windows to Venus occur every 19 months. In some cases multiple successful probes were launched with the same design at the same time so I'll group those together (the Soviets launched two similar/identical missions per launch window they actually used to ensure mission success through redundancy). I'll label each mission with ...


22

The pressure exerted on a surface area under the ideal gas law is $P = \frac{\rho k_B T}{\mu}$ with the following notation: $\rho$ being the volume mass density (or simply density) $k_B$ is the Boltzmann constant $T$ is the temperature in Kelvin $\mu$ is the mean molecular mass in g/mol On Earth $\mu_E \approx 29$, while on Venus it is $\mu_V \approx 44$. ...


21

Nobody really knows for sure. And there's two, nay three more odd things about it's rotation on its own axis, namely: It is the only planet in the Solar system that rotates retrograde, i.e. clockwise, when all other planets rotate prograde, or anticlockwise, on their axes, Latest findings (merely a good month ago as of writing this answer) revealed that ...


20

An orbit has an angular momentum that is conserved. That angular momentum vector keeps the orbit at a fixed orientation in inertial space. As a planet orbits the Sun, the local time of the ascending node moves around the clock over that planet's year. The only way for an orbit to be Sun-synchronous is for there to be a torque applied to the orbit to ...


20

One picture is worth all your base to us. Before we sent probes to Venus we had no pictures of its surface. Whether it lands or not you have to penetrate the atmosphere of Venus to take pictures of it, whereas the surface of Mars can be easily seen through its weak atmosphere from afar. Most of the information about Venus has been derived from the ...


19

To some extent, we can answer the question for the tools currently available to life, using basic physical principles, and the answer to that is "no". This needs consideration of the atmosphere of Venus and the nature of photosynthesis. The goal of terraforming would primarily be to sequester (or "lock away") the extra atmosphere. So we mainly need to ...


18

The mass of Mars is so small, and its magnetic field so weak that it cannot hold onto carbon for a long period of time, making almost all of it to escape. (Venus and Earth are close to identical in size, Mars is much smaller) Venus does not really leak that much of its atmosphere, the only noticeable exception is that all hydrogen compounds are virtually ...


18

No, because thermonuclear weapons don't make holes in clouds, they make clouds. First you have a fireball: And then you get a big mushroom cloud: Neither the fireball or mushroom cloud are see-through. Even if the bomb managed to push Venus' thick atmosphere out of the way all you'd see is fireball and mushroom cloud before it closed right back up again ...


18

Question: Why not bring cyanobacteria and fertilizer to the atmosphere of Venus to improve conditions for life there by producing oxygen ? ... Only a few scientists have speculated that thermoacidophilic extremophile microorganims might exist in the lower-temperature, acidic upper layers of the Venusian atmosphere. It has been speculated that the clouds ...


17

The early Venera probe hulls were designed for an atmospheric pressure of 25 bar. Barometers were designed for 10 bar. This was in line with what was then assumed to be the surface conditions. At the time, it was thought that the surface temperature of Venus was approximately 300C, with an atmosphere consisting mainly of carbon dioxide and nitrogen at about ...


17

What does the discovery of phosphine mean for the future of Venusian exploration? It certainly adds some impetus. However, The discovery has not yet been independently confirmed. This alone is very important. What if the discovery was not a discovery at all? If confirmed, devising a measuring device that can withstand the extremely acidic nature of the ...


16

The simple answer is that taken as a whole the Venera missions didn't land particularly close together. Starting with Venera 4: The overall spread of Venera landing sites (when you include the probes that didn't survive to the surface) is nearly 110° of longitude. For comparison, the spread of Luna landing sides on the map you provided of the moon is ...


16

The same WP article on Venus in fiction referenced by the OP documents one specific scientist who believed, in a nonfiction sense, that Venus is indeed the world envisioned by mid-20th-Century writers: In 1918, chemist and Nobel Prize winner Svante Arrhenius, deciding that Venus's cloud cover was necessarily water, decreed in The Destinies of the Stars that ...


15

I'm going to only start calculating delta v from Earth Escape, using this Delta V table. Furthermore, I'll assume we are starting from LEO, and we want to get in to a low orbit of the appropriate planet. The numbers turn out to be: Venus- 3.5 km/s to Venus, 3.3 km/s to Low Venus Orbit Mars- 3.6 km/s to Mars, 2.1 km/s to Low Mars Orbit. Bottom line is, it ...


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