Next proposals for discovery missions have been revealed

[insert_name]

NASA has revealed the next set of candidates for the next two discovery missions. There are four proposals

davinci+: a Venus orbiter lander combo to obtain data on the atmosphere and surface of venus

IVO:a Jupiter orbiter to study IO similarly to how Europa clipper will study Europa

trident: Neptune/Triton flyby

Veritas: Venus orbiter to obtain high resolution maps of venus and better understand it's internal geology

NASA will pick up to two of these missions for launch, which ones do you think they should pick? I am in favor of davinci+ and IVO as I think we should be doing more at Venus and davinci+ has a lander whereas veritas+ doesn't. For IVO I think that it is the better option for the outer solar system as it doesn't require an RTG and will remain around the target longer than Trident's single flyby.

Link: http://nasa.gov/press-release/nasa-selects-four-possible-missions-to-study-the-secrets-of-the-solar-system via

[kerbiloid]

Io and Triton.

It looks puny to measure the Venusian carbon dioxide p&T once again, and it's too early to plan a route for Venusian rover.

Edited February 14, 2020 by kerbiloid

[Space Nerd]

Venus lander and triton, because it's about the time to send something to venus surface and Neptune.

Although extra budget to include ivo is nice.

[ThatGuyWithALongUsername]

2 hours ago, Space Nerd said:

Venus lander and triton, because it's about the time to send something to venus surface and Neptune.

Although extra budget to include ivo is nice.

Thing is it isn't a lander, just an atmosphere probe.

 

Theoretically the Russians will be sending a lander... but funding is... uh...

...the mission is NET "2026 or 2031."

 

So we'll see

 

(Personally, my vote is for IVO and Trident, but I really wish NASA had the funding to just select all the finalists in these situations. Same goes for New Frontiers missions)

[Space Nerd]

9 hours ago, insert_name said:

Venus orbiter lander combo

Hugh?

[Wjolcz]

Hopefully Venus because its clouds act strangely and it would be nice to know what causes them to absorb UV light. It's also close so we wouldn't have to wait that long for all the sweet science.

Edited February 14, 2020 by Wjolcz

[kerbiloid]

Spoiler

  

1 hour ago, Space Nerd said:

10 hours ago, insert_name said:

Venus orbiter lander combo

Hugh?

Orbits, then falls.

 

[Starman4308]

I'm on the fence about Trident. If NASA secures funding for proper flagship missions to the ice giants, it becomes partially redundant, and dips further into limited stockpiles of Pu-238.

Other than Trident with its external factors, my two favorites would be Da Vinci+ and Veritas. Sorry Io.

[Guest]

Io! 
And something else... 

Io is super cool! Figuratively of course  
Id be happy if it was all Jovian stuff tbh \o/

[MinimumSky5]

The thing with Trident, is that it's going to use an alignment of Jupiter and Neptune that we wont get again for several decades, so I'm kind of in favour of Trident for that reason.

Obligatory Scott Manley video!

 

 

Edited February 16, 2020 by MinimumSky5
Fixed Youtube link

[Guest]

11 minutes ago, MinimumSky5 said:

The thing with Trident, is that it's going to use an alignment of Jupiter and Neptune that we wont get again for several decades, so I'm kind of in favour of Trident for that reason.

Obligatory Scott Manley video!

https://youtu.be/6txkItycgYQ

Ooo, well in that case Trident sounds ok too. :0

[Guest]

Trident and IVO. Leave Venus to the Russians, they have a lot of experience with designing stuff to survive there. NASA is going to have one or two jumbo-sized rockets to launch those missions on, so it makes sense to go far.

[wumpus]

On 2/14/2020 at 9:12 AM, kerbiloid said:

  Hide contents

  

Orbits, then falls.

 

From the Scott Manley video, it looked like it took a second pass for the orbiter to catch up to the lander.  I can't imagine that being in the final plan, requiring the lander survive a protracted period on the Venusian surface collecting data to be uploaded to the orbiter.  Perhaps the lander will transmit directly to the Deep Space Network (or just Earth), but that's not how lander/orbiter combos typically work (and even less likely on Venus).

[kerbiloid]

1 hour ago, wumpus said:

From the Scott Manley video, it looked like it took a second pass for the orbiter to catch up to the lander.  I can't imagine that being in the final plan, requiring the lander survive a protracted period on the Venusian surface collecting data to be uploaded to the orbiter.  Perhaps the lander will transmit directly to the Deep Space Network (or just Earth), but that's not how lander/orbiter combos typically work (and even less likely on Venus).

As all previous Venusian landers were surviving for about an hour before die from overheating, and the same is the Venusian low orbital period, the orbiter must do just one turn before receiving the lander's death note and transferring it to the Earth.

To transmit directly to the Earth, the lander should have more powerful radio and antenna, which is problematic in that conditions.

To survive longer, the lander should contain more complicated and massive cooling system, so be large and more heavy. Unlikely they will send something much bigger than the traditional 1 m sphere.
Also the only thing the lander has to do is to take one sample of ground, put it  in the pocket, irradiate and start sending report with a hope in the heart that the orbiter will finish the circle before the radio burns.

Edited February 16, 2020 by kerbiloid

[StrandedonEarth]

I’ve always wondered about sending a Venus lander with a water/ice tank. The ice keeps it cool longer, then when the resulting steam is vented it could be used to generate power for a more powerful radio/instrument package. 

[Guest]

Do note, electronics can be made to operate at high temperatures, up to 400 degrees Celsius (at least, according to a quick Google search). This seems to be a fairly recent advancement, so a lander could likely be made to operate on the surface with minimum refrigeration. Of course, how much can you do with such electronics is another matter, but it should be possible to ditch the heavy pressure hull, or to reduce its size significantly. 

Considering how far forward these proposals are, SLS and maybe even BFR would be available. Sending something large would not be out of the question. Of course, the Russians should have their own HLVs by then, so TBH, I'd rather have US handle the missions to outer planets.

[Space Nerd]

I think the lander beams all the data to the orbited when it flies by(the time is probably enough).

[ThatGuyWithALongUsername]

1 hour ago, Dragon01 said:

Do note, electronics can be made to operate at high temperatures, up to 400 degrees Celsius (at least, according to a quick Google search). This seems to be a fairly recent advancement, so a lander could likely be made to operate on the surface with minimum refrigeration. Of course, how much can you do with such electronics is another matter, but it should be possible to ditch the heavy pressure hull, or to reduce its size significantly. 

Considering how far forward these proposals are, SLS and maybe even BFR would be available. Sending something large would not be out of the question. Of course, the Russians should have their own HLVs by then, so TBH, I'd rather have US handle the missions to outer planets.

Mean surface temp of Venus is 462° C... but that isn't the only problem. Sulfuric Acid isn't known for being friendly to spacecraft, and radiation levels are very high as a result of Venus having no magnetic field. The pressure is also immense on the surface- far higher than 1 atm

 

I would love a full-fledged long-distance rover or something like that too, but there's a reason it still hasn't been done despite Venus being the easiest planet to get to.

 

And it DEFINITELY wouldn't fit in a discovery-class budget. We're talking a flagship-size mission here, and without as much interest in Venus as in other destinations for those missions I don't see that happening soon. But I do believe the challenges could eventually be overcome.

 

I womder if a balloon designed to float just *under* the cloud layer (instead of higher up) could be more doable? It could get the first optical maps of Venus, instead of radar, with infrared spectroscopy and stuff like that for composition too! It would also give plenty of long-term data on that part of Venus' atmosphere and wind patterns, too- heck, if it got lucky and passed directly over one, it *could* give insight on the possibly active volcanism! (Heck, pictures from that perspecive would just be really cool, too)

 

This would still have many challenges- it would still have to deal with higher temperature, pressure, radiation and scidity than normal- but not quite as badly as a surface probe would need to and without the need to protect as many complex moving parts as a rover would. Heck, maybe the refridgeration system could pump heat into the balloon.

 

Some challenges are more unique to this concept, though- first off, mission control can't control where it flies, it goes wherever the wind currents go. Second, you'd need to make a balloon that can stay aloft at the right altitude for as long ss possible. But I wonder if it's doable...

Edited February 17, 2020 by ThatGuyWithALongUsername

[Guest]

20 minutes ago, ThatGuyWithALongUsername said:

Mean surface temp of Venus is 462° C... but that isn't the only problem. Sulfuric Acid isn't known for being friendly to spacecraft, and radiation levels are very high as a result of Venus having no magnetic field. The pressure is also immense on the surface- far higher than 1 atm

Refrigerating from 460 to 400 is less of a problem than from 400 to 40 (though still a problem). Sulfuric acid is easy to deal with, just coat the outside with teflon or some other heavily fluorinated plastic. It can corrode exposed metal, but doesn't do much harm to plastics. As for pressure, it's less a problem than it seems. Pressure differential is a problem, things get crushed if the pressure outside is larger than pressure inside+material strength (or if pressure is unevenly applied, but that's never the case with static pressure in a gas). If there's no inside, there's no problem. Solid-state electronics should have no issues with it. Venera probes were pressurized to protect old-style electronics inside, which couldn't stand vacuum, nevermind conditions on Venus. Designing electronics to work unpressurized is certainly an unorthodox (and expensive) line of research, but I think it's something to consider for a future mission, as it would allow for dispensing with the submarine hull for landers, and support development of high temperature electronics for more mundane applications.

Edited February 17, 2020 by Guest

[Hannu2]

5 hours ago, Dragon01 said:

Refrigerating from 460 to 400 is less of a problem than from 400 to 40 (though still a problem). Sulfuric acid is easy to deal with, just coat the outside with teflon or some other heavily fluorinated plastic. It can corrode exposed metal, but doesn't do much harm to plastics. As for pressure, it's less a problem than it seems. Pressure differential is a problem, things get crushed if the pressure outside is larger than pressure inside+material strength (or if pressure is unevenly applied, but that's never the case with static pressure in a gas). If there's no inside, there's no problem. Solid-state electronics should have no issues with it. Venera probes were pressurized to protect old-style electronics inside, which couldn't stand vacuum, nevermind conditions on Venus. Designing electronics to work unpressurized is certainly an unorthodox (and expensive) line of research, but I think it's something to consider for a future mission, as it would allow for dispensing with the submarine hull for landers, and support development of high temperature electronics for more mundane applications.

Teflon can handle somewhat more than 200 C. It or other plastics are not solution at Venus. But is dry gaseous sulfuric acid a bad problem? Probaly there is some metal which can handle it. For example common type of stainless steel 316L can handle dry HCl gas at near 1000 C. Add little water vapor and situation will be not so good.

100 bar is not very difficult pressure to handle (with simple steel or titanium sphere) and cheap large rockets we seemingly get in near future will help to solve mass issues of such pressure vessel. Electronics and electric isolation would be the worst problems. They investigate high temperature electronics made from GaN or SiC (not because Venus but to get compact power electronics with cheaper cooling systems), but I think 460 C is too much for current level. It think there is no suitable battery chemistry too and RTGs will work very poorly if cold temperature is 460 C.

5 hours ago, ThatGuyWithALongUsername said:

Mean surface temp of Venus is 462° C... but that isn't the only problem. Sulfuric Acid isn't known for being friendly to spacecraft, and radiation levels are very high as a result of Venus having no magnetic field. The pressure is also immense on the surface- far higher than 1 atm

Do you really know that radiation level is high at Venus surface (except thermal IR due to high temperature)? It is hard to believe that any radiation from space or upper atmosphere penetrate the massive atmosphere and I also do not know any reason to expect more radioactive materials at surface than on Earth.

[kerbiloid]

Spoiler

  

3 hours ago, Hannu2 said:

Do you really know that radiation level is high at Venus surface (except thermal IR due to high temperature)? It is hard to believe that any radiation from space or upper atmosphere penetrate the massive atmosphere and I also do not know any reason to expect more radioactive materials at surface than on Earth.

I suggested here to drop thermonukes on Venus and gather samples of ground from mushroom clouds, but as this idea still is not implemented, the radiation levels should be normal.