Exploration of Venus - Is it worth going?

Mark S · 2002-06-06 11:17:13

The moon and Mars are the most popular targets of our desire to explore beyond the earth. But the exploration of Venus was also on NASA's drawing boards as recently as the early 1960's. Of course, we now know that Venus is a hellish and unforgiving planet. Still, it would be a terrific engineering challenge to get humans there someday. Once we set up outposts on the moon and Mars, and once we can mine and possibly destroy near-earth asteroids, would it be worth the time, money, and effort to send humans to Venus?

Byron · 2002-06-06 12:45:57

Not for a very long time, at least. Not only is Venus hot enough to melt lead, the atmosphere is 100 bar...strong enough to crush just about anything that might land there. A human mission would be so dangerous, and so costly, it may never happen.

More likely, I think Venus will be used as the Solar System's universal trash dump; all the nuclear waste we don't need to have here on Earth now and Mars in the future, etc, could be dumped there. There is no way we'd be able to transform Venus, either, as its 'day' is 89 days long, and there's such much CO2 around that it'd be impossible to get rid of it all. To sum it up, Venus is a place we'd be better off staying away from, at least in my opinion.

B

Josh Cryer · 2002-06-06 12:59:09

Because it's 100 times as dense as Earths atmosphere it would be an ideal place for floating platforms. Energy can be obtained from the hot atmosphere, a limitless supply. Surviving on the surface would be near impossible, unless we deployed solar shades and froze the atmosphere to the surface.

But I really hope Venus doesn't become a nuclear garbage dump...

Phobos · 2002-06-06 18:14:27

Not to mention that you'd practically need a Saturn V just to launch back into space from Venus. It would be even harder getting into space from Venus than it would be from Earth because the gravity is the same but the weather is merciless.

Shaun Barrett · 2002-06-06 19:52:29

I think Byron is right. No human is likely to set foot on Venus in the foreseeable future, for obvious reasons. Although, if it were absolutely necessary, I'm sure we could come up with the technology to do it.
4.6 billion years ago, the sun was about 2/3 as bright as today. Earth, and particularly Mars, were probably struggling to stay warm enough for liquid water to exist on the surface. Venus, on the other hand, would have been at the ideal distance from that young sun to experience balmy surface conditions. For this reason, I have often wondered whether life might have developed there quite early in the piece.
If life did appear, it is quite conceivable that conditions on Venus could have remained clement enough to sustain that life for up to 2 or 3 billion years. (i.e. up to about 2 billion years ago). Then, of course, we know what happened!
Just lately, we've discovered that plate tectonics on Venus have stalled (assuming there ever were any) and, therefore, the planet's internal heat builds up catastrophically over time. Studies of the surface, including crater counts, have shown that no part of the Venusian surface is more than 700 million years old. This led to the conclusion that volcanism on an awesome scale, fuelled by the massive internal heat build-up, causes magma to completely resurface the planet on a regular basis.
Why do I bring all this up? Well, I used to imagine a scenario wherein a heavily insulated and refrigerated human expedition to Venus dug up fossils, or even evidence of technology! Fanciful, I know! But it seemed like a good enough reason to face all the rigours and actually go there.
Now we know that the rocks from that ancient time, when living creatures may have swum in warm seas, have all been consumed in the volcanic convulsions that have happened every 700 million years since the water dried up. There's nothing there but hot, sterile, solidified lava and any signature of past life has been completely erased. A tragedy!
So, for me, the only reason I could think of to send humans to Venus has disappeared. It's a h***-hole with no saving graces I can think of at the moment.
But hold off on the nuclear waste dumping, just in case I think of another good reason to go there!!

Tom Jolly · 2002-06-07 12:35:27

Even if we were to put up sun shields to block out 100% of the sunlight, I'll bet Venus would take centuries to cool down to a point where someone could live on it. It'd certainly be an interesting experiment in thermodynamics! Too bad there's no water in the atmosphere (or surface...of course). I often thought it might be a good idea, though, to steal a few million cubic kilometers of Venus's CO2 atmosphere and move it to Mars.

TJ

Shaun Barrett · 2002-06-07 18:56:41

Hi Tom! Somebody else suggested the same thing a few months ago but I tried to talk him out of it!
Most of the experts seem to think we'll have enough CO2 on Mars as it is. What we'll probably need more than anything else is nitrogen, to add bulk to the atmosphere without all the worrying side-effects of CO2 ... like death by poisoning!!
I brought up Kim Stanley Robinson's idea of automated cyclers bringing billions of tons of nitrogen from Titan to Mars, but Adrian wasn't impressed for some reason! I think the prospect of all that huge-scale tinkering with the solar system made him nervous!
Still, we're bound to dream up some good use for Venus if we keep trying.

Phobos · 2002-06-07 23:11:30

Why do I bring all this up? Well, I used to imagine a scenario wherein a heavily insulated and refrigerated human expedition to Venus dug up fossils, or even evidence of technology! Fanciful, I know! But it seemed like a good enough reason to face all the rigours and actually go there.

Where've you been!! Didn't you see those photos of Venusians floating around the clouds in their blimps?

Shaun Barrett · 2002-06-08 23:06:40

No. But then, I've only ever smoked the stuff they sell with filter tips attached!

Palomar · 2002-06-11 11:33:42

Josh wrote: "Not for a very long time, at least. Not only is Venus hot enough to melt lead, the atmosphere is 100 bar...strong enough to crush just about anything that might land there. A human mission would be so dangerous, and so costly, it may never happen."

What's interesting is that Sir Arthur C. Clarke has one tiny (enclosed, of course) human settlement on Venus and an underground mining colony established on Mercury [!] in his novel _Rendezvous with Rama_. Although he's a scientist, it surprised me that he would project future human settlement on either of those two planets. Too bad he's not here to explain his rationale for those items in the novel.

--Cindy

Phobos · 2002-06-11 13:34:30

Actually it might be somewhat possible to have a colony on Mercury considering that it's temperature plummets dramatically during the night. If there are permanently shaded craters or mountain ranges on Mercury it might be possible. Who knows, there might even be ice there in eternally dark areas like the moon. Would make a nice place to set up a solar observatory. Yeah but I agree about Venus, I think it's going to be a very long time before humans ever touch down on that planet. It's heat and gravity is to much of a barrier.

Palomar · 2002-06-11 15:51:29

Phobos wrote: "Actually, it might be somewhat possible to have a colony on Mercury considering that it's temperature plummets dramatically during the night. If there are permanently shaded craters or mountain ranges on Mercury it might be possible. Who knows, there might even be ice there in eternally dark areas like the moon. Would make a nice place to set up a solar observatory."

*It definitely was an unexpected and pleasant surprise in the book. I'm always thinking of solar system exploration, settling, and colonization in terms of going outward and away from the Sun. The underground Mercury colony -- the concept of it -- really captured my imagination in the story; the uniqueness of it, and the fact that I don't know of another author so bold and daring as to suggest a Mercurial colony some day! Geez, how big would the Sun appear from Mercury? You couldn't look at it naked-eye, of course...

--Cindy

Phobos · 2002-06-11 22:00:28

Geez, how big would the Sun appear from Mercury? You couldn't look at it naked-eye, of course...

It'd nearly take up the whole sky, but anybody out looking at it directly probably wouldn't live long enough to enjoy the sight anyway, not unless they're wearing one hell of a spacesuit. Really though I never actually thought about looking at a star from that distance with my own eyes. I bet you'd gain new respect for its size.

Shaun Barrett · 2002-06-13 00:59:50

Phobos writes that Venus will not host a human mission in the foreseeable future because its heat and gravity are too much of a barrier.
Do I detect a misapprehension here?
Venus is certainly hot as h***, and it's atmosphere is massive (90 bar, I thought). But the planet's mass is only 4/5ths that of Earth and it's surface gravity about 0.9g
Actually, it's a weight-watchers dream ... the average human would be about 7 kilograms lighter, and no diet required!!
Hope I'm not being pedantic in bringing this up!

Phobos · 2002-06-13 02:13:40

The reason I brought up the problem with Venus's gravity is not because it's hostile to the human body but rather because colonists who land there will need launch vehicles on par with those we use on Earth to get back into space. Unless the Venusian colonists can manufacture rockets on par with the launchers we use on Earth to launch people into space, those colonists will be on Venus for a very long time.

Shaun Barrett · 2002-06-14 06:09:21

Looks like I got the wrong end of the stick! I half suspected I had.
My apologies, Phobos!
???

Phobos · 2002-06-14 15:08:58

No problemo. It's probably logical to assume anyway that by the time we develop the technology to colonize Venus getting out of the gravity well will be no problem anyhow.

Dayton3 · 2002-06-14 20:28:19

I think the exploration of Venus will go something like this:

1) Large unmanned probes will land and take soil samples. Using a nuclear reactor to heat carbon dioxide as propellant.

The probes will be capable of "jumping" using short bursts from its reactor powered engine. traveling to other locations several hundred meters away before returning to Earth.

2) When fusion propelled engines come into use, I can see properly shield manned missions will be able to orbit the planet at length and use advanced rovers telerobotically to explore.

3) Finally, humans will land on Venus. But not before powered exoskeletons are developed to carry the hundreds of pounds of life support equipment necessary to keep a human alive under such conditions.

Such exoskeletons would allow for much higher detailed exploration.

Anyway, thats my opinion.

Shaun Barrett · 2002-06-15 00:39:30

This whole humans-to-Venus thing has so many huge problems that I just can't imagine it being attempted for a long time.
The pressure at the surface on Venus is 90 atmospheres, or thereabouts. That's equal to the pressure at a depth of 900 metres in one of our oceans, or 2,950 feet! Just over twenty years ago, a guy called Phil Nuytten, probably THE expert on deep-sea diving, produced a 1000 ft rated hard suit. This suit keeps its wearer in a 1 atmosphere environment down to a depth of a thousand feet and yet, through the use of rotary joints, allows a degree of mobility and dexterity. I believe that this is still the current state-of-the-art deep sea diving suit.
The pressure on Venus is very nearly THREE TIMES the pressure that our best suits can handle! We haven't dealt with the temperature problem at all yet, and already we're in trouble. When you factor in the 470 deg.C day and night temperature and the light drizzle of concentrated sulphuric acid, it becomes obvious (at least to me) that Venus is a no-go area! Our technology doesn't even come close to matching the challenges of an expedition to Venus.
And the next problem is almost certainly the real show-stopper: Why go there?! I have faith that, given time and sufficient incentive, human ingenuity would overcome even the horrors of a brief vacation on Venus! But what for? I know the quest for knowledge for its own sake is a noble enterprise but, in this case, we could gain so much more knowledge elsewhere for the same investment of resources.
Venus is a lost cause for the moment. Let's concentrate on Mars.

Christina · 2002-06-15 06:07:05

it's going to take a very powerful reason to get anyone to be inspired to develop the technology to explore the Venusian surface properly.

Unless it's got something we really, really need, I can't see it happening at all.

Sad but true.

Aetius · 2002-06-16 05:39:53

If you could colonize a Near-Earth Object, preferably a burnt-out comet core or suchlike, moving it into orbit around Venus would allow you to harvest the Venusian atmosphere for volatiles. Using robotic, nuclear-powered ramjet tankers (like Zubrin's NIFT vehicles from his book "Entering Space"), colonists could skim the upper atmosphere for valuable materials.

A viable proposition? Anyone's guess. I'd thought of it myself years back, so it was cool to see asteroid colonists in Venusian space in KSR's "Blue Mars".

RobS · 2002-06-17 00:52:42

I have done some thinking about Venus exploration, and suspect at some point it will be worthwhile remotely from Venus orbit (where communications times are milliseconds, rather than minutes). The Mars Direct architecture will provide humanity with the equipment to go to Venus orbit and continued development of earth orbiting stations will give us the ability safely to put a staffed station in an elliptical Venus orbit (one that would only take a few thousand miles per hour of delta-vee to head back to the earth).

The key to robotic exploration of Venus may very well be solar-powered "high-flier" airplanes that would fly for years above the cloud cover. With solar panels on the tops and bottoms of the wings--to catch the reflected sunlight off the clouds and the light coming directly from the sun overhead--the planes could get up to four times the solar energy per square meter as a solar panel in earth orbit. Such planes could fly fast enough to stay perpetually in sunlight (the atmosphere circulates around Venus at a high altitude at about 250 mph, if I recall).

Solar powered planes would provide continuous meteorological data. They could also send microwave beams of power through the clouds to robotic stations on the Venus surface, which would rely on the microwave power to run air conditioning units! Even electronics fry at the temperatures measured on the Venus surface. Robotic surface stations could probably be equipped with metal balloons filled with hydrogen gas to lift them up, let them float somewhere else, then land again (or they could use propellors powered from beamed energy from above; the surface winds are very light, just a few mph).

Throughout one Venus day, a surface station could drift from place to place on the Venus surface or just above it, photographing, taking samples, measuring the chemical composition of rocks. As the Venus day at a particular spot on the surface came to an end, that would probably spell the death of the station unless microwave power could be sent down from space. A very small, battery-powered airplane could come down from the high-flier to the surface station, hook onto a basket of rock samples, and fly it back up to the high flier, where heavier equipment could carry out more detailed chemical analysis.

I suspect a sample return mission would be possible using a high-flier. The samples would be brought up to the high flier from the surface by small battery-powered aircraft or balloons. The high flier could contain in it a small multiple-stage rocket. Possibly the high flier could slowly extract water from the Venus atmosphere--it has water, but not a huge amount--and using solar power, slowly make methane and oxygen, just like the Mars Direct system does. If the high flier flew at an altitude of 40 to 60 miles, it would be in a zone with a lower atmospheric pressure and temperature than the surface of the earth. Over a year or so, the high flier's rocket could accumulate a few tons of propellants. The samples would be transferred to the rocket's cargo area, the rocket would be released, and it would fly to orbit, where either the human crew would retrieve it or it would rendezvous with another rocket. There are designs right now for 6000-kg solid-fueled rockets to fly 100 kg from the Earth's surface to low earth orbit. I suspect from a high-flier, 100 kg could be put into a low Venus orbit by a smaller rocket than that.

As the technology for surface exploration improved, perhaps a station in Venus orbit with a dozen people would be needed to run the surface probes.

Another possibility is a small reusable minishuttle that would descend to a high flier, rendezvous with it and dock for months, refuel using the high flier's water extraction system, then fly back to orbit. Remember that several percent of Venus's water is deuterium; it's far more common in Venus's atmosphere than Earth's or Mars's. Possibly the deuterium could be harvested and flown to orbit cheaply enough to be resold on Earth (where it is worth $10,000 per kilogram).

I don't see people ever landing or even flying regularly into the Venus atmosphere; it's not necessary. But I do see them running things real-time from Venus orbit. We'll see.

-- RobS

Byron · 2002-06-17 06:24:10

Interesting reading by RobS...the point I wish to make, to put it simply, is: Why? Why would we want to go to all this trouble to explore a planet that we know to be the harshest place in the entire Solar System (except for the Sun, of course!)...and virtually a zero chance of ever providing a future home for humanity. (Just try and build a planet-wide solar shield and somehow increasing the planet's 1-in-89-day spin cycle to 1-in-24 hours..wouldn't you rather terraform the Moon first?..at least it'd be easier..lol)

For the life of me, I just don't see what could be down on Venus's hellish surface that could be of any redeeming value to humanity whatsoever. Knowledge is always good, but there's sooo much more out in the Solar System (not to mention the stars beyond) that *should* rate higher than Venus on the exploration front. Wouldn't you rather see what's under Europa's icy surface, a liquid ocean of H2O that makes Earth's oceans seem puny by comparision? The rings of Saturn? Even eccentric, lonely Pluto would be more interesting than Venus (and NASA is planning a potential mission there in the next decade.)

Excuse me for being biased against Venus...but I think there are plenty of reasons to just leave that place alone and focus our attention to Mars and beyond..indeed, the rallying call of spacefaring humanity should be "Outward ho, to the stars we go!"

'Nuff said....

B

RobS · 2002-06-19 01:13:10

I quite agree with Byron that people will probably never live on Venus, and terraforming it is probably too difficult and expensive. But I think remote exploration of the planet from orbit--rather like the current exploration of the Antarctic--is probably of scientific value, especially considering that Venus is almost exactly the same size as earth and may have had oceans in its first billion years or so. For all we know, life may have evolved on Venus first, then was seeded onto Earth and Mars as a result of impacts. We could all be Venusians! Whether that can ever be determined, however, is unclear.

I do see two possible economic uses of the planet: (1) harvesting deuterium from the atmosphere (though it may not be cheap enough to be economical); and (2) it might be a good place to send earth-crossing asteroids. We could crash them there if we wanted to get rid of them, or we could engineer close passes to Venus--grazing the atmosphere--to put them in Venus orbit. Their materials could be harvested and sent back to Earth in small enough chunks to be safe. I suspect (2) is doubtful, though, because we can harvest materials from the asteroids where they are. I doubt there is an economic advantage to concentrating a half dozen or so at a time in Venus orbit and working on all of them with one mining team. The only advantage would be to create a subsidy for Venus exploration; it would be safer to explore Venus from orbit if you were inside a cocoon of several meters of rock and dirt to absorb cosmic rays, and then you might as well haul in an asteroid, build a base out of it, explore Venus, and do some mining at the same time.

As for Europa, it will be very hard to explore it directly by humans because it is imbedded in Jupiter's van Allen belts, and thus is bathed in very lethal levels of radiation. Ditto for Io. Callisto is outside of the radiation belts. Ganymede is inside, but has a magnetic field of its own that may deflect the radiation enough to make the surface safe (I don't know).

Someone asked whether Venus's temperature would change if its rotation rate were speeded up. I don't think so.

-- RobS

New Mars Forums

Announcement

#1 2002-06-06 11:17:13

Re: Exploration of Venus - Is it worth going?

#2 2002-06-06 12:45:57

Re: Exploration of Venus - Is it worth going?

#3 2002-06-06 12:59:09

Re: Exploration of Venus - Is it worth going?

#4 2002-06-06 18:14:27

Re: Exploration of Venus - Is it worth going?

#5 2002-06-06 19:52:29

Re: Exploration of Venus - Is it worth going?

#6 2002-06-07 12:35:27

Re: Exploration of Venus - Is it worth going?

#7 2002-06-07 18:56:41

Re: Exploration of Venus - Is it worth going?

#8 2002-06-07 23:11:30

Re: Exploration of Venus - Is it worth going?

#9 2002-06-08 23:06:40

Re: Exploration of Venus - Is it worth going?

#10 2002-06-11 11:33:42

Re: Exploration of Venus - Is it worth going?

#11 2002-06-11 13:34:30

Re: Exploration of Venus - Is it worth going?

#12 2002-06-11 15:51:29

Re: Exploration of Venus - Is it worth going?

#13 2002-06-11 22:00:28

Re: Exploration of Venus - Is it worth going?

#14 2002-06-13 00:59:50

Re: Exploration of Venus - Is it worth going?

#15 2002-06-13 02:13:40

Re: Exploration of Venus - Is it worth going?

#16 2002-06-14 06:09:21

Re: Exploration of Venus - Is it worth going?

#17 2002-06-14 15:08:58

Re: Exploration of Venus - Is it worth going?

#18 2002-06-14 20:28:19

Re: Exploration of Venus - Is it worth going?

#19 2002-06-15 00:39:30

Re: Exploration of Venus - Is it worth going?

#20 2002-06-15 06:07:05

Re: Exploration of Venus - Is it worth going?

#21 2002-06-16 05:39:53

Re: Exploration of Venus - Is it worth going?

#22 2002-06-17 00:52:42

Re: Exploration of Venus - Is it worth going?

#23 2002-06-17 06:24:10

Re: Exploration of Venus - Is it worth going?

#24 2002-06-19 01:13:10

Re: Exploration of Venus - Is it worth going?

Board footer