Author Topic: NASA develops computer chip that can survive 500°C temperatures & pressures on Venus  (Read 10312 times)

Offline Star One

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This must be a major boost for Venus exploration especially if you want to put a rover down on the surface.

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Nasa researchers have made a breakthrough in space technology by developing a computer chip that can survive in extreme heat on the planet Venus for multiple weeks without any form of protection or cooling system.

Scientists from Nasa's Glenn Research Center have developed a computer chip that can survive Venus' surface temperatures of up to 470°C (878°F), as well as the 9 MPa atmospheric pressure, which is 90 times higher than on Earth, without a cumbersome system to keep it cool.

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The breakthrough was possible by building the chip out of silicon carbide (SiC) – a new type of ceramic semiconductor material that is able to cope with high voltages and temperatures, as well as making sure that the tiny wires that connect transistors and other components in a circuit (known as "interconnects") are able to survive the extreme conditions too.

The researchers demonstrated that their chip was able to continue to function at 1.26MHz for 521 hours continuously (21.7 days) when placed in the Glenn Extreme Environments Rig (GEER), a machine specially designed to emulate the temperature and pressure on Venus for hundreds of hours at a time.

http://www.ibtimes.co.uk/nasa-finally-develops-computer-chip-that-can-survive-500c-temperatures-venus-1605664

Offline john smith 19

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This must be a major boost for Venus exploration especially if you want to put a rover down on the surface.

http://www.ibtimes.co.uk/nasa-finally-develops-computer-chip-that-can-survive-500c-temperatures-venus-1605664
This has a long way to go. So far they have 2 transistors running. Granted they run without any packaging or cooling but this is a long way from a processor, or an ADC (likely pretty important for data collection devices).

Space probe processors are not noted for their extreme speed but 1.23MHz is at the level of the early 70's
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Online launchwatcher

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This has a long way to go. So far they have 2 transistors running. Granted they run without any packaging or cooling but this is a long way from a processor, or an ADC (likely pretty important for data collection devices).
I skimmed the linked paper: http://aip.scitation.org/doi/full/10.1063/1.4973429

and a supplementary doctument: ftp://ftp.aip.org/epaps/aip_advances/E-AAIDBI-6-068612/GEER2SupplementaryAIP.pdf

They're a little further along than that -- 36 transistors on two IC's (one with 12, the other with 24), wired up as NOT gates.   Add a second input to form NOR or NAND gates and you're in business for digital logic...

Offline high road

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This must be a major boost for Venus exploration especially if you want to put a rover down on the surface.

http://www.ibtimes.co.uk/nasa-finally-develops-computer-chip-that-can-survive-500c-temperatures-venus-1605664
This has a long way to go. So far they have 2 transistors running. Granted they run without any packaging or cooling but this is a long way from a processor, or an ADC (likely pretty important for data collection devices).

Space probe processors are not noted for their extreme speed but 1.23MHz is at the level of the early 70's

Does this problem remain if the lander only has to execute orders given by a separate module which stays at more moderate temperatures?

Offline Rei

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Processor performance is sort of a moot point either way because the point of long-term surface modules is to do mundane data collection, aka a surface weather or seismic station.  We're not talking "thinking machines" doing terrain analysis like Opportunity and Curiosity.  :)  Indeed, while there have been some surface rover proposals (including the curious wind-propelled Zephyr concept), there seems to be more interest in exploring the surface with bellows or phase-change balloons.  The former seems to be more of a hot topic right now. 

But I guess the real moot point is that Venus missions never actually get funded by NASA, so...

Offline high road

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... ESA and Roscosmos need to stop impacting on Mars and try landing something on Venus for a change/again?

Just saying  ::)

Offline haywoodfloyd

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NASA should stop wasting money on probes to Venus. They know what an inhospitable place it is. There is nothing to be gained from spending hundreds of millions of dollars just to confirm what they already know.
Use the money to set up a permanent moon base to gain knowledge and experience for an eventual trip to Mars.

Offline Star One

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NASA should stop wasting money on probes to Venus. They know what an inhospitable place it is. There is nothing to be gained from spending hundreds of millions of dollars just to confirm what they already know.
Use the money to set up a permanent moon base to gain knowledge and experience for an eventual trip to Mars.

What so now everything they do should be focussed on human colonisation. I'd think you'd find plenty who disagreed with that approach. You could just as easily say humans have no place in exploration and it should all be done by robots.
« Last Edit: 02/10/2017 12:32 pm by Star One »

Offline Manabu

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Does this problem remain if the lander only has to execute orders given by a separate module which stays at more moderate temperatures?
Then you really have the problem of making a radio that can work at those temperatures and pressures. In the autonomous rover case, you could make do with a second probe that attaches to it after it finishes it mission to transmit the data quickly.

Well, there are still maany problems yet to be solved for a rover mission to Venus. Maybe it is easier to terraform it first...

Offline john smith 19

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Returning to the topic of this thread.

There's a long way to go. Just the variation in transistor parameters across a 76mm wide wafer should tell you this is not a mature technology.

You'll also be needing RAM and ROM for this. ROM can be done in various technologies but RAM is difficult, unless you go with static ram, IE 4 transistors to a bit.

What it may do is lower the cooling requirements for such a system and hence lengthen it's life expectancy.

TBH you could build a probe with with no digital electronics. The only transistors would be in the radio,but it would be heavier, more difficult to calibrate, less able to adjust to entry and landing conditions and a lot more difficult to design.

Yes it is an achievement. To see the sort of level of processing power on a probe this is an excellent introduction

https://history.nasa.gov/computers/contents.html

Part II is especially relevant. The Voyager architecture especially so. Reading between the lines it would have been implemented as a chip called the LS181, a group of gates (no registers) that could do all the logic and arithmetic functions between 2 four bit numbers. By having multiple 4 bit registers attached to its output and input and suitable gating the 4 bit ALU could act as an 8, 12, 16 or any sized word length processor, at proportionately lower speed. Such a chip would need 36 2 input NAND gates to function.  Just about what has been demonstrated, since a NAND gate is basically the standard function provided by a 2 input MOS transistor.
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Offline Rei

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NASA should stop wasting money on probes to Venus. They know what an inhospitable place it is. There is nothing to be gained from spending hundreds of millions of dollars just to confirm what they already know.
Use the money to set up a permanent moon base to gain knowledge and experience for an eventual trip to Mars.

What so now everything they do should be focussed on human colonisation. I'd think you'd find plenty who disagreed with that approach. You could just as easily say humans have no place in exploration and it should all be done by robots.

Even concerning human colonization Venus is an excellent destination, at ~45-55km in the high latitudes.  Most Earthlike place in the solar system outside of Earth, and normal Earth air is a lifting gas (aka, you can live inside the envelope).  See Landis 2003 for more.  There's huge amounts of power and mineral resources.  Water's on the low end, but the planet hands you a wide range of important industrial chemicals straight from the air.  Sulfuric acid, hydrochloric acid, phosphoric acid, hydrofluoric acid; base gases like carbon dioxide, nitrogen and noble gases at orders of magnitude higher concentration than on Mars; etc.  Even iron has been detected in Venus's clouds (iron chloride) - suggested on the order of 1% of the mass of H2SO4.  And the surface, while inhospitable, is absolutely accessible; the Soviets were doing so with technology they developed in the 1960s.  They found getting to and studying the surface of Venus much easier than the surface of Mars.  There's multiple technologies being testedin the lab (bellows and phase change balloons) for bringing up minerals from the surface, and the atmosphere is thick enough that you could dredge it.

The only thing that keeps us from doing more with Venus is that NASA virtually never funds missions to Venus. Since 1978, there's been only one NASA mission launched to Venus (not counting flybys en route to other destinations), and none since 1989.  That's humiliating. 3-4 decades of scientists constantly proposing exciting new missions of a vast diversity to answer huge questions, but Mars gets the lion's share of the funding, then the outer planets, and our closest neighbor, our twin, gets nothing.

And I profoundly disagree with the "what they already know".  We know vastly less about Venus than we do Mars.  There are some really massive unanswered questions about the planet, many with direct applicability to our ability to both exoplanet searching and, more importantly, our ability understand the Earth (and it's fate).  Just to pick one example: it appears that about 500 million years ago Venus resurfaced almost its entire surface with basaltic lava.  Can Earth-sized planets just up and do this at random points in time, or is this something Venus-specific?  If Earth has the potential to do this too, that's pretty terrifying, and we really owe it to ourselves to understand it.

To give an idea of how little we know about Venus, here's just a few of the mysteries. 

 * Where's it's mercury?  Mercury is volatile, it has a significant vapour pressure even in Earth conditions. Crustal mercury on Venus should be in the atmosphere.  But measurements have constrained it to over *3 1/2 orders of magnitude* less than models predict.  Where on Earth (er... Venus) is it?

 * What makes up Venus's lower cloud deck?  We're pretty solid on the fact that the upper and middle cloud decks are mainly sulfuric acid (minor constituents, we're fuzzier on that...).  The lower cloud deck is still debated.  There's a good argument that it's mainly phosphoric acid, and that the lower haze is a phosphorus pentoxide virga.  But lots of people have their own theories!

 * What's the mystery UV absorber?  Are we talking iron chloride or polysulfides?  Because some people strongly disagree about which one deserves credit!

 * Does it rain or snow on Venus, and if so what kinds?  People can't even agree on whether it rained/condensed/snowed on the Vega probes themselves.

 * What does it rain, snow, etc?  There's dozens of possibilities at different layers.

 * What are the radar reflective areas in the highlands?  They appear to be different types, too.  Theories include everything from snows of iron pyrite to frosts of tellurium.

 * Are the highlands remnants of old granitic continents as some theorize, possibly survivors from the days that Venus had Earthlike oceans?  If so, wow, what can we find in the rocks?

 * What and where is Venus's lightning?  We keep detecting it, and even have recordings of its thunder, but we never see its flashes, and Cassini couldn't spot any signals from it at all on its flyby. 

 * What's going on with Venus's volcanism?  Amazing that in such a clearly volcanic world we know next to nothing about actual eruptions there.  We have a couple "we maybe detected something" finds, but nothing more.

 * What made Venus's rivers, like Baltis Vallis?  Longest riverbed in the solar system and it's just speculation what carved it.  And the "best theories" are bizarre in their own right, like carbonatites.  Can you imagine a carbonatite river that size?

 * Does Venus's atmosphere ever condense out to a supercritical foam?  It's been argued that it actually does at times.

I could keep going for ages.  We know so dang little about Venus, our sister planet.  And this technology is part of a line that can help us understand it.  Seismometers from multiple locations around a suspect active volcano would allow us to seismically sound the subsurface, for example.  That'd  be a treasure trove of data.
« Last Edit: 02/10/2017 08:12 pm by Rei »

Offline Eric Hedman

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I could see some great spin-offs to this technology.  There are a lot of hot environments in engines and industrial processes that could use electronics that operate at such high temperatures.

Offline john smith 19

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Even concerning human colonization Venus is an excellent destination, at ~45-55km in the high latitudes.  Most Earthlike place in the solar system outside of Earth, and normal Earth air is a lifting gas (aka, you can live inside the envelope).  See Landis 2003 for more.  There's huge amounts of power and mineral resources.  Water's on the low end, but the planet hands you a wide range of important industrial chemicals straight from the air.  Sulfuric acid, hydrochloric acid, phosphoric acid, hydrofluoric acid; base gases like carbon dioxide, nitrogen and noble gases at orders of magnitude higher concentration than on Mars; etc.  Even iron has been detected in Venus's clouds (iron chloride) - suggested on the order of 1% of the mass of H2SO4.  And the surface, while inhospitable, is absolutely accessible; the Soviets were doing so with technology they developed in the 1960s.  They found getting to and studying the surface of Venus much easier than the surface of Mars.  There's multiple technologies being testedin the lab (bellows and phase change balloons) for bringing up minerals from the surface, and the atmosphere is thick enough that you could dredge it.

The only thing that keeps us from doing more with Venus is that NASA virtually never funds missions to Venus. Since 1978, there's been only one NASA mission launched to Venus (not counting flybys en route to other destinations), and none since 1989.
Somewhat depressing but this does suggest a possible approach. Using Venus to increase velocity and change direction seems quite a regular tactic. On that basis it seems like the best shot at getting a probe to Venus would be as a piggyback unit on other missions.

Obviously this would be very much a secondary payload so it's pretty much at the discretion of the primary mission but it would be a way to collect some data. The main mission would collect the data from the probe during it's flyby (however long that lasted) for transmission back to Earth. Atmospheric chemical composition seems like a key question right now. A GCMS should be capable of fitting inside a unit the size of a cubesat and surviving long enough to answer some of those questions. IIRC Mariner Venus used Sapphire or Ruby windows for passive sensing but some kind of active light source to excite the surrounding atmosphere then read it's spectrum should also be possible.

A more flexible (but slower) strategy would be  to split the secondary payload into a probe section and an orbital relay unit. In principle over a series of Missions this would collect further data about Venus and set up an infrastructure that would mean prolonged, possibly surface missions could transmit to orbit at higher data rates, like the one operating around Mars.

I think a rover is still a very long way off. 
I could see some great spin-offs to this technology.  There are a lot of hot environments in engines and industrial processes that could use electronics that operate at such high temperatures.
That and increased radiation hardness and the theoretically higher mobility (and hence clock frequencies) have been major drivers for this technology.
« Last Edit: 02/10/2017 10:16 pm by john smith 19 »
MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline Robotbeat

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You don't really need much RAM other than a few bits. With a few hundred gates, you can digitize data from an instrument, do some forward error correction, and transmit it to an elliptical orbit relay satellite. The relay satellite can contain a bunch of RAM, a big dish, and a lot of power to transmit to Earth, relieving the Deep Space Network of having to constantly listen. But anyway, the point is the probe doesn't actually need any storage if it's constantly transmitting data as it is received. It also doesn't need commanding, as it just takes data.

There are is a seismometer prototype that was run at high temperature as well. And a high temperature camera (based on the simpler Viking design which scanned with just a few pixel elements) could be used.

Power can come from High temp ASRG, high temp RTG (older RTGs operated at high enough temperature that they could dump heat even at Venus temperatures), solar (yes, there is some light down there), or even very large thermal batteries, which actually like to operate at high temperature anyway.

Here is a design study based on this concept, baselining the high temperature RTG: https://www.researchgate.net/publication/272522839_Venus_high_temperature_atmospheric_dropsonde_and_extreme-environment_seismometer_HADES

« Last Edit: 02/11/2017 12:16 am by Robotbeat »
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Offline A_M_Swallow

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I suspect that chip would work in the mid day sun on the Moon. It could form part of a sensor or activator. The main computer could be in a shaded part of the machine. I do not know if the chip still works in extreme cold.

Offline Rei

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Power can come from High temp ASRG, high temp RTG (older RTGs operated at high enough temperature that they could dump heat even at Venus temperatures), solar (yes, there is some light down there), or even very large thermal batteries, which actually like to operate at high temperature anyway.

Here is a design study based on this concept, baselining the high temperature RTG: https://www.researchgate.net/publication/272522839_Venus_high_temperature_atmospheric_dropsonde_and_extreme-environment_seismometer_HADES

Concerning solar (since a lot of people often are incredulous about that one):

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150016298.pdf

Like you said, you can't get much power out of it... but you can get some!  And it doesn't take much.

Offline Robotbeat

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Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

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Offline high road

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NASA should stop wasting money on probes to Venus. They know what an inhospitable place it is. There is nothing to be gained from spending hundreds of millions of dollars just to confirm what they already know.
Use the money to set up a permanent moon base to gain knowledge and experience for an eventual trip to Mars.

Except checking our theories why Venus looks like it does today. You know, science. Just about every probe or telescope we send up in space has forced us to review our models. Especially those about planetary formation and evolution. Venus might hold the clues why planets with life at the surface are rare, and it's probably more complex than current models. One and a half data points makes for very bad science.

Offline Robotbeat

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There's tons we don't know about Venus. It may have had oceans like Earth, for all we know. Or even life, before the runaway greenhouse effect took over. It's possible that we are descended from Venusian organisms.  We don't know unless we go and check it out.
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Offline TakeOff

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What planetary scientists really want to have on the surface of Venus for a longer period of time (like a Venus year), is seismometers. The major mystery of Venus is that it was resurfaced only about 0.3 billion years ago. Was it because of some kind of volcanism? Venus is as large and old as the Earth, it is the perfect laboratory for geophysics. Seismometers are sensitive things, so I imagine that it might be hard to do.

Offline philw1776

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Lots of interesting planetary science still remaining on Venus.  But as to human colonization fantasies, what makes Mars accessible is its low escape velocity.  Venus is much closer to Earth in that respect.  The rocket equation is an unrelenting exponential and huge rockets with over a thousand tons of propellant would be needed to return even a mini-ITS from Venus.  Not. Gonna. Happen. until/unless far, far from available anytime soon (many decades +) radical new rocket propellant systems are available, q.v. solid hydrogen.
« Last Edit: 02/11/2017 05:38 pm by philw1776 »
FULL SEND!!!!

Offline Rei

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Yeah, Landis.

He works on all the neatest things  ;)

Offline Rei

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But as to human colonization fantasies, what makes Mars accessible is its low escape velocity.  Venus is much closer to Earth in that respect.

Low gravity is also what makes Mars potentially hazardous to human health, as well as being part of the reason it has such a thin atmosphere, which means people have to live in (heavy) pressure vessels that bear (heavy) radiation shielding.  It's also low light, infrequent launch windows, longer transit times,  a bit more min delta-V for transfers, wide temperature swings, generally quite cold, your habitat is stuck in a single location, and aerobraking / landing is difficult (and has killed many craft - Venus you can safely enter and land a hollow titanium sphere all the way at the surface without any sort of aeroshell, ablative, or parachute at all),  The atmosphere has to be compressed a hundredfold to give you the density of gas resources Venus has, and there's an order of magnitude lower diversity in them.  For most things that Venus gives you straight from the air (all your major industrial acids, and even things like iron), on Mars you have to mine the surface - surface mining being a process well known for breakdowns and need for regular replacement of parts and other consumables.  On Venus, "mining" is little more than a gas scrubber - aka, absorption.

Quote
The rocket equation is an unrelenting exponential and huge rockets with over a thousand tons of propellant would be needed to return even a mini-ITS from Venus

Who says an ITS style system would descend into the atmosphere?  For Venus, the optimal scenario is for ITS to aerobrake and meet up with ascent stages from habitats, then leave.  No refill,. but also no descent into a gravity well***.  The ascent  stages reenter and float in the exact same manner as the intiial habitat did at arrival (aka, ballute), and thus have effectively unlimited time to dock.  Residual propellants provide the lifting gas (for example, MON -> hot N2 + O2).  Docking with airships was being done in the early 20th century (Macon / Akron), and is now a lot easier (you can have a tethered drone connect them from a distance, reduce lift in the lower one, then winch).

** Side benefit: The ITS spaceship is rated for 12 launches (full refill and burn), meaning six trips to Mars and back (see their spec sheet).  For Venus, it's only one full fill and burn per round trip (broken into two smaller burns), so double the lifespan.  The capital costs of the spaceship are by far the biggest element of cost in SpaceX's ITS proposal.  And because of the short transit times and frequent launch windows, it spends less of its time wasted drifting around in space.
« Last Edit: 02/11/2017 06:13 pm by Rei »

Offline Robotbeat

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Watch until the very end, after the credits:
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Offline Rei

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Re, Venus's atmopsphere, ~55km, ~70° latitude
« Last Edit: 02/16/2017 05:51 pm by Rei »

Offline john smith 19

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Re, Venus's atmopsphere, ~55km, ~70° latitude
That's basically a point value.  I was thinking more in terms of a profile as the probe dropped through the atmosphere.  In particular the "2nd cloud level" I think you mentioned?

It's obvious from this chart either the Venus atmosphere model needs revision or a more sensitive instrument needs to be sent. However I presume the original instrument was expected to be sensitive enough to detect the compounds at the concentrations the model predicts they should be at anyway.
MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline Rei

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Re, Venus's atmopsphere, ~55km, ~70° latitude
That's basically a point value.  I was thinking more in terms of a profile as the probe dropped through the atmosphere.  In particular the "2nd cloud level" I think you mentioned?

It's obvious from this chart either the Venus atmosphere model needs revision or a more sensitive instrument needs to be sent. However I presume the original instrument was expected to be sensitive enough to detect the compounds at the concentrations the model predicts they should be at anyway.

Middle cloud layer.  :)  The (oversimplified) layout of Venus's atmosphere, top down, is upper haze -> upper cloud -> middle cloud -> lower cloud -> lower haze -> lower atmosphere

Yes, our knowledge of Venus's atmosphere needs a *lot* more study.  I only included that point reference because that's the habitable zone.  There's not just one instrument; there've been a number of them, but all old technology - the last manmade probe to enter Venus's atmosphere was in the 1980s.  And furthermore some of the data received is contradictory.  And unfortunately, part of the problem is that they don't show things at levels models have predicted (mercury being a good example - in the 1960s it was theorized that it was the main constituent of Venus's clouds, yet we haven't found any at all).  We really can't explain why Venus's atmosphere is as it is at this point in time - we can only plug the data that we have into models and try to determine what else should be there at levels lower than past probes would have been able to detect.  The lower atmosphere is the least understood, since it's very difficult to probe from remotely (whether from Earth or from orbit). .
« Last Edit: 02/11/2017 10:29 pm by Rei »

Offline Lar

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NASA should stop wasting money on probes to Venus. They know what an inhospitable place it is. There is nothing to be gained from spending hundreds of millions of dollars just to confirm what they already know.
Use the money to set up a permanent moon base to gain knowledge and experience for an eventual trip to Mars.

What so now everything they do should be focussed on human colonisation. I'd think you'd find plenty who disagreed with that approach. You could just as easily say humans have no place in exploration and it should all be done by robots.

We can keep building robots that we launch from here, OR we can get out there into the asteroid belt, into LEO, on Luna, on Mars, and as we build up capability, send robots and humans from those places. Long term the overall cost will go down. Yes, Lewis and Clark added a lot of info but we really learned the most about the Americas when we had hordes of people everywhere, learning and building and doing.

But of course, that requires CHEAP access to space. SLS and ULA aren't the pathway there. (well, ULA might be eventually)

Debating THAT point (which seems obvious to me) is off topic.
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Offline john smith 19

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What planetary scientists really want to have on the surface of Venus for a longer period of time (like a Venus year), is seismometers. The major mystery of Venus is that it was resurfaced only about 0.3 billion years ago. Was it because of some kind of volcanism? Venus is as large and old as the Earth, it is the perfect laboratory for geophysics. Seismometers are sensitive things, so I imagine that it might be hard to do.
Depends.

If you make the seismometer sensitive in 1 axis IE the vertical (which you can do with flexure designs( you lock the design until after landing, then release it to start sensing.

For real cleverness you use a passive design without batteries, in a capacitance bridge design that's driven by the interrogation signal from a Venus orbiter. This is then used to modulate an uplink signal, giving you seismic (or other) data while the orbiter is overhead. It is also the mother of all RFID systems.  :)

A bimetallic strip and Bordon gauge can be used to mechanically vary the resonant frequency of RF circuits in a way similar to the passive RF bug developed by the Russians for use in the US Embassy in Moscow during the 1940's (The Thing). So you get an analog FM signal over the temperature and pressure range.

[EDIT One interesting ides to improve sensitivity is to make them "null" instruments, where the device generates a "correction" signal  (which could be mechanical as well as electrical) and the output is the error signal needed to do so. In weighing systems this is how a unit can weigh the entire Shuttle stack to the nearest Kg. IE 1 in 2^22 accuracy

For bonus points an atmospheric spectrometer would be nice. I'd though you'd need a controlled active light source to do this but Pioneer Venus apparently used a passive scheme measuring the solar spectrum and identifying the absorption lines. So something similar could use a prism or diffraction grating moving a part of spectrum across a detector and the angle of the prism and the sensor output are both uplinked to the orbiter to compare against samples measured at similar temp and pressure.

That leaves the Holy Grail of Venus measurements, actual colour images of the surface.

This makes every other measurement look easy by comparison.  :( ]

Obviously it's only giving readings during the orbiters pass overhead, so what's happening the rest of the time is a mystery, but it's better than nothing.  :(
No batteries, no active RF systems and presumably no active cooling. So in principle capable of lasting quite a long time.
« Last Edit: 08/24/2017 09:50 pm by john smith 19 »
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