Sign in to follow this  
Followers 0

Radiation hardening and SpaceX

51 posts in this topic

@MikeMelgaback off. There is no shame in saying.

Quote

Oh great! I've learnt something from somebody who knows more than me

 

You are just making a fool of yourself by being married to the idea Musk has done something NASA couldn't.

Using ordinary hardware and massive redundancy.

 

In fact you're coming across like an anti-vaxxer. Ignoring long scientific papers that debunk your pet theory, and quoting snippets or telling me to go ask people I can't ask.

 

Quote

More modern hardware can be found in space; there are laptops on the ISS, the 2007-vintage ThinkPad T61p running Debian, Scientific Linux, and Windows 7. They are being replaced by HP ZBook 15s, which will run the same mix of Linux distributions and Windows 10. The Linux systems act as remote terminals to C&C MDM, while the Windows systems are used for email, the web, and recreation.

But those laptops are not high-availability, high-performance computers. They're ordinary laptops that are expected to fail. Indeed, there are more than a hundred laptops on the ISS and most are defunct.

 

The space station's new supercomputer

The two articles I've quoted negate every single claim you have made about radiation hardening. 

 

On 02/09/2021, 11:45:11, MikeMelga said:

The link you provided shows clearly that example, and that in LEO this is a non-issue.

 

WTF!

Quote
  1. Radiation hardened chips are not needed at all. CubeSats are just fine with chips from the nearest store, very ordinary Lenovo laptops work on the ISS without any problems, and even NASA-commissioned Orion onboard computer is based on a commercial microprocessor!

Don't tell me you were naive enough to grab the first sentence that seemed to support your position!

The whole section this paragraph is found in is about misconceptions about space electronics.

 

Either debunk the entire articles, or back off.

0

Share this post


Link to post
Share on other sites

Quote MikeMelga

Quote

Of course I read the article, here is the interesting part. Did you read it?

 

 

 

https://aviationweek.com/dragons-radiation-tolerant-design

 

BTW, SpaceX flies these above LEO and nothing is fried, at least for the few hours the missing lasts. The article already mentions that it can work over LEO, with more considerations, like external shielding.

 

Of course anybody can do this, not just SpaceX. So why was oldspace still doing it?

0

Share this post


Link to post
Share on other sites

Are we talking about space electronics or throw away electronics below the van Allen belt

Of course a modern notebook could survive hours on a sub van Allen flight.

 

Modern notebooks can survive years on the ISS which is also sub Allen.

The ISS uses one specific notebook, running nasa unix, which I speculate has fault tolerance as part of the Linux kernel root for mission critical control

And lots of burner notebooks even running windows for conferencing, social media etc. They are burner because they will die within years if not months.

 

The simple facts are:

On the ground with massive data centre you need storage hardened to soft event. That is covered by crc codes

Below the van Allen belt you need hardened electronics for protection against hard events or very short life span

Above the van Allen belts where you're being bombarded with cosmic rays you need strongly hardened electronics or it will die within days.

 

Cosmic rays are actually near light speed particles of electrons, positrons, protons, helium nuclei, and positrons, and anti protons.

These don't get far into the atmosphere because they convert their kinetic energy into photons. These ultra high energy photons are also termed cosmic rays.

0

Share this post


Link to post
Share on other sites
4 hours ago, MadAxeMurderer said:

On the ground with massive data centre you need storage hardened to soft event. That is covered by crc codes

Below the van Allen belt you need hardened electronics for protection against hard events or very short life span

Above the van Allen belts where you're being bombarded with cosmic rays you need strongly hardened electronics or it will die within days.

From the 2012 SpaceX article I mentioned, I think they summarize it very well: they don't have individual components which are radiation hardened. Their system itself is radiation hardened, through multiple CPU usage (6 for the Dragon). And NASA was OK for LEO.

 

From your link, in the bottom it says that you can actually use normal CPUs above Van Allen belt, but you need external shielding, which for normal satellites makes it unfeasible due to weight limitations. But if it is a very large rocket it's not an issue to carry a few kilos of shielding. Im sure that's what they will do with Starship.

0

Share this post


Link to post
Share on other sites
Quote

radiation hardenend hardware. Then SpaceX came and introduced another concept: multiple computers who vote for a decision. Much more relisience, much more redundancy, much more performance and much cheaper.

@MikeMelga

 

Dear me I completely misunderstood.

 

Your whole point is that spacex spending a few hours below the van allen belt, didn't need radiation hardening against hard cosmic ray events and indeed simply used redundancy and voting to handle soft cosmic ray events. 

 

Just like airplanes, and ground data centres.

Revolutionary, inspirational, genius. Duh! It's fucking obvious: hours below the van allen belt. trivial environment and duration

 

You still need radiation hardening for electronics to survive more than a few years below the van allen belt and to survive hours outside the van allen belts.

By survive I mean not have large enough holes punched in the silicon structure so it still operates.

 

I asked the NASA guy why not just use shielding, and he said the weight of shielding is unacceptable. Satellite engineers worry more about weight than cost. We can save 100gramms, it will only cost 1 million to do so. Awesome you're a hero!

 

Now I don't know about spending years in inter planetary space i.e. going to Mars. I would speculate it might be simpler to wrap the whole electronics assembly in shielding because the geometries needed for surviving years become ridiculous.

 

BTW I talk a lot about the van allen belts. They are regions of space around Earth kept relatively clear of cosmic rays by the Earth's magnetic field. 

They are not perfect. In fact they focus the particles onto the Earth's poles causing the Northern lights (also in Antarctica)

1

Share this post


Link to post
Share on other sites
50 minutes ago, MadAxeMurderer said:

@MikeMelga

 

I asked the NASA guy why not just use shielding, and he said the weight of shielding is unacceptable. Satellite engineers worry more about weight than cost. We can save 100gramms, it will only cost 1 million to do so. Awesome you're a hero!

 

Now I don't know about spending years in inter planetary space i.e. going to Mars. I would speculate it might be simpler to wrap the whole electronics assembly in shielding because the geometries needed for surviving years become ridiculous.

 

AFAIK, Starship will have a radiation shelter in the middle of the ship. Among other things, I think the water tanks will be around it. The main computers could be located there.

Extra shielding is not so problematic, the ship has a payload of 100-150 tons to Mars surface, having a few kilos of lead won't change it much.

 

Also it won't be years, transit times will be between 3 to 6 months. There is a nice study from some department inside NASA that shows that a 3 month transit time takes more fuel, but saves so much in water and food that it might be better. Mars surface does not have serious radiation problems. So a 2 way trip would take between 6 to 12 months.

 

I've also cross read a study a few years ago that providing you have enough power, you can create a powerful magnetic shield, but I don't think this would be mass-effective for the upcoming designs.

0

Share this post


Link to post
Share on other sites
1 hour ago, MikeMelga said:

AFAIK, Starship will have a radiation shelter in the middle of the ship. Among other things, I think the water tanks will be around it. The main computers could be located there.

Extra shielding is not so problematic, the ship has a payload of 100-150 tons to Mars surface, having a few kilos of lead won't change it much.

 

Also it won't be years, transit times will be between 3 to 6 months. There is a nice study from some department inside NASA that shows that a 3 month transit time takes more fuel, but saves so much in water and food that it might be better. Mars surface does not have serious radiation problems. So a 2 way trip would take between 6 to 12 months.

 

I've also cross read a study a few years ago that providing you have enough power, you can create a powerful magnetic shield, but I don't think this would be mass-effective for the upcoming designs.

 

You are concentrating on the computers too much !

 

THe human body is expected to suffer much on the trip to and back from Mars, the inside cabin will need to be protected from cosmic rays for the humans to live, once you have protected the humans in STARSHIP, you can put the computers in with the humans.

 

According to this https://phys.org/news/2016-11-bad-mars.html, and many other articles, The people on MARS will need to be protected from cosmic rays, as they are much more preverlant on MARS than earth because, MARS has no van allan belt.

 

If STARSHIP goes to Mars, mankind will see what the real effects of living out of the van allan belt is like, for long times, the only people who have done it so far, where the moon landings, and that was only a couple of people for a short time.

 

Sure protect the computers, but humans need just as much protection

 

 

 

 

 

 

 

1

Share this post


Link to post
Share on other sites

@yesterday, nobody is saying we don't need protection. But the level of protection for the computers will have to be bigger than for humans, as computers cannot self-heal (except memories marking bad blocks).

 

The radiation on Mars surface is not much higher than on Earth. Staying inside with minimum shielding is enough to match Earth values.

One study from NASA shows a round-trip total radiation of 0.6 sieverts, compared to a maximum of 1 sievert for total career of an astronaut.

https://web.archive.org/web/20190307100926/http://pdfs.semanticscholar.org/d4f6/8022dd4b96755933bccdc586bbeb2e031eb3.pdf

 

This is the perfect example of FUD. There are much more dangerous problems, like failure of mission, than a small probability of radiation problems.

If you ask a future astronaut if he is concerned about radiation, he will tell you he is more concerned about surviving the landing or returning home.

 

 

0

Share this post


Link to post
Share on other sites

Well actually you seemed to be saying that another of Musk's revolutions was zero shielding for electronics.

 

I think NASA really places highest priority on its astronaut's lives. However if the any mission critical computing dies the astronaut's are dead as well. 

And yes better a slightly irradiated living astronaut than an un irradiated dead one.

 

Water is indeed an excellent shield. But I'd speculate that on the ISS, and on a Mar's mission water is captured and recycled.

Certainly sweat and urine is easy to process. Capture from faeces might not be so good, dehydration is energy expensive. 

 

But the bottom line is a Mar's mission won't consume 2 litres of water per astronaut per day. It will lose millilitres per as every drop of water drunk by an astronaut, or washed with is in a closed system

1

Share this post


Link to post
Share on other sites
1 hour ago, MadAxeMurderer said:

I think NASA really places highest priority on its astronaut's lives. However if the any mission critical computing dies the astronaut's are dead as well. 

And yes better a slightly irradiated living astronaut than an un irradiated dead one.

That's one of the reasons not much good has come from NASA since the 1970's. Current Astronaut chance of death is well below what US military found in Iraq or Afghanistan.

This lead to very expensive and long programs, which aligns with oldspace pork barrel projects.

 

Quote

 

Water is indeed an excellent shield. But I'd speculate that on the ISS, and on a Mar's mission water is captured and recycled.

Certainly sweat and urine is easy to process. Capture from faeces might not be so good, dehydration is energy expensive. 

AFAIK, this is already done at ISS. But after recycling, Starship could put the water back in the center. Also helps if weight is kept in the center, to save attitude thrust.

I think they will need to have large solar panels, probably more than 100% redundancy.

 

Quote

But the bottom line is a Mar's mission won't consume 2 litres of water per astronaut per day. It will lose millilitres per as every drop of water drunk by an astronaut, or washed with is in a closed system

Yeah, but food is unavoidable.

0

Share this post


Link to post
Share on other sites
2 hours ago, MikeMelga said:

That's one of the reasons not much good has come from NASA since the 1970's.

 

Actual, the reason why NASA has not done much good in the last years, is that the US Government cut their funding, so much that it had to drop the MARS project. It carried on with the shuttle as that was the only choice left. We have to remember, the US government has and has always wanted private companies  to develop this technology and keep state funded NASA on a relatively low budget. SpaceX has benefited from this in that, SpaceX gets a lot of development work, while NASA and EASA get very little money.

See here about the NASA cuts  Moonport, Ch22-8 (nasa.gov)

 

2 hours ago, MikeMelga said:

Current Astronaut chance of death is well below what US military found in Iraq or Afghanistan.

This lead to very expensive and long programs, which aligns with oldspace pork barrel projects.

Yeah well, both projects are made as save as possible, it just in a war zone with hundreds of thousands of solders, some are going to get hurt, unfortunaly. while the environment astronauts live in can be controlled in a more easy way

 

You are comparing Apples and oranges

Quote

 

 

 

0

Share this post


Link to post
Share on other sites
12 hours ago, yesterday said:

Actual, the reason why NASA has not done much good in the last years, is that the US Government cut their funding, so much that it had to drop the MARS project. It carried on with the shuttle as that was the only choice left. We have to remember, the US government has and has always wanted private companies  to develop this technology and keep state funded NASA on a relatively low budget. SpaceX has benefited from this in that, SpaceX gets a lot of development work, while NASA and EASA get very little money.

See here about the NASA cuts  Moonport, Ch22-8 (nasa.gov)

That's a misconception. NASA is well funded. Problem is, the bulk goes to pork barrel projects like Shuttle or SLS.

https://www.planetary.org/space-policy/nasas-fy-2021-budget

SpaceX is just showing it's possible to do much more with much less money.

 

Obama created these COTS projects, which foster competition and gave SpaceX the opportunity to grow.

 

As an example, old NASA projects show a Mars program to cost at least $400B. Yes, that's not feasible with current budget. But SpaceX plans points to something between $2.5 and $10B, depending if it is a one-shot or the start of colonization. A fully self sustainable Mars colony could be done for $100B, by SpaceX.

We are talking of differences over 100x. NASA could easily pay for that program just by canceling SLS and Orion!

 

This will put NASA in a corner. First, NASA is forbidden from developing their own equipment if there is something available off the shelve. Meaning SLS and Orion have to be cancelled as soon as Starship demonstrates orbit flight. Second, NASA has to carefully decide what role will it have for Mars. Either it embraces SpaceX quickly and funds a Mars mission, or SpaceX will go alone (paid by the highest bid) and NASA will lose relevance.

 

As an example, NASA is spending over $6B per year on programs that can all be replaced by Starship by a fraction of that cost, perhaps 5-10x cheaper.

Even Bezo's Blue Origin could make it much cheaper than oldspace!

0

Share this post


Link to post
Share on other sites

NASA is very good a doing what's never been done before. 

Others like SpaceX are much better at taking the technology they develop and paths they blaze and repeating it more cheaply.

 

Saying NASA is a disaster and SpaceX will wipe them out is like saying movie producers are old school, because I can buy a bootleg DVD in China or Vietnam for 10c

 

Why can Vietnam produce a DVD for less than 10c when Hollywood and Bollywood producers spend millions to make a DVD.

0

Share this post


Link to post
Share on other sites
5 hours ago, MikeMelga said:

That's a misconception. NASA is well funded. Problem is, the bulk goes to pork barrel projects like Shuttle or SLS.

https://www.planetary.org/space-policy/nasas-fy-2021-budget

SpaceX is just showing it's possible to do much more with much less money.

 

NASA and SpaceX are about completely different things

 

NASA, is monitoring space to see if big rocks are coming from space to Earth, they monitor Global warming, they have people looking at how to land drones on other planets, they have a hand in the Hubble, to name just a few things they do, NASA roll is to investigate space etc and get there when required, they do a massive amount of work which we never get to hear about. NASA was more or less made to take on the Russians, to get a man to the moon, its was never set up for profit.

 

SpaceX, just want to make rockets to get stuff in to space like satellites and men to the space station for money, they do not do the massive amount of research that NASA does, they just want the profit. Sure STARSHIP seems less likely to make a profit, but up until now they have different objectives.

 

Do not get me wrong, SpaceX developed a working reusable self landing rocket which is amazing and should help in the search of space, for  a lower price.

 

By the way the shuttle stopped being funded years ago.

 

Must admit, I cannot see a good long term reason to live on MARS, as said, people who go there, cannot go outside without a space suit and must live under the ground most of the time, who would what to do that ???, Sure as a step, to planet which can support human live I can understand it, but not living on   MARS its self long term

 

 

 

 

 

5 hours ago, MikeMelga said:

Obama created these COTS projects, which foster competition and gave SpaceX the opportunity to grow.

 

 

 

 

 

 

 

1

Share this post


Link to post
Share on other sites
17 hours ago, yesterday said:

 

NASA and SpaceX are about completely different things

 

NASA, is monitoring space to see if big rocks are coming from space to Earth, they monitor Global warming, they have people looking at how to land drones on other planets, they have a hand in the Hubble, to name just a few things they do, NASA roll is to investigate space etc and get there when required, they do a massive amount of work which we never get to hear about. NASA was more or less made to take on the Russians, to get a man to the moon, its was never set up for profit.

Agree, but still 30% of the budget goes to those huge space exploration projects which take decades and do nothing. And most of the rest is related.

 

17 hours ago, yesterday said:

Must admit, I cannot see a good long term reason to live on MARS, as said, people who go there, cannot go outside without a space suit and must live under the ground most of the time, who would what to do that ???, Sure as a step, to planet which can support human live I can understand it, but not living on   MARS its self long term

TBH I think the next goal should be asteroid mining. And I think SpaceX is not talking about it, but they will do it. Mars is more inspirational than mining blocks of metal in space.

 

Mars for living... it's hard to justify. The only reasons could be tourism, elderly life in low G and libertarian utopias.

 

For example let's say you have problems at late age related with walking. Walking on Mars would be much easier. In fact an indoor gym could allow people to jump 2 meters in the air. Some crazy sports could come from that.

But again... Mars economy would be driven by services. While asteroid mining has a much stronger economical feasibility.

 

I think Musk is crazy enough to sell a lot of stock and finance a 1000 people colony within 20 years. Then eventually he dies or money ends and the thing is left abandoned.

Does not matter, the infrastructure and technology will fuel asteroid mining, which I believe will be the main reason for a permanent space settlement.

 

0

Share this post


Link to post
Share on other sites
20 hours ago, MadAxeMurderer said:

NASA is very good a doing what's never been done before. 

Others like SpaceX are much better at taking the technology they develop and paths they blaze and repeating it more cheaply.

 

Saying NASA is a disaster and SpaceX will wipe them out is like saying movie producers are old school, because I can buy a bootleg DVD in China or Vietnam for 10c

NASA hasn't developed anything relevant in the past 40 years. It's a repetition of the 1960's and 1970s.

The SLS uses engines developed in the 1970's. Orion is an oversized Apollo capsule. Same shit, just more expensive.

0

Share this post


Link to post
Share on other sites

That Nasa hasn't developed new rockets might be true. I don't know. I care far more about what the rockets carry.

In the same way I care that Greta Thunberg speaks to governments.

I don't really care what kind of car, boat, plane took her there.

 

But NASA has developed the Hubble and Watt telescopes, the Mars rover, and helicopter. 

The Parker solar probe

A lot of less sexy satellites that monitor atmospheric, oceanic, arctic climate change.

Even more satellites that only interest particle physicists, and cosmic ray groupies 

 

The voyagers which have passed the termination shock, and heliopause, thus officially exited the solar system.

Voyager1 is 21 light hours from Earth! 

 

All SpaceX has done is build a better rocket with unhardened computing elements.

That doesn't even exit the protection of the Van allen belt.

Well if SpaceX develop 10% light speed travel as MikeM probably believes comes next they can catch Voyager in 1 week!!!

 

I'm not trying to diminish SpaceX just trying to inject some realism into you, or at least this discussion

0

Share this post


Link to post
Share on other sites

@MadAxeMurderer, Hubble, Voyager were very old projects, I've said the past 40 years.

Mars rover and others are basically the same since the first landing in 1971. It's a repetition with a bit more tech. Nothing new!

Most of those weather satellites were developed between 1975 and 1985. The recent ones are just the same, with more recent tech.

 

14 hours ago, MadAxeMurderer said:

But NASA has developed the Hubble and Watt telescopes

Webb?

 

Quote

All SpaceX has done is build a better rocket with unhardened computing elements.

That doesn't even exit the protection of the Van allen belt.

It does... at least one mission had a 2nd stage burn several hours after passing the belt... this was done to prove it could do it, to qualify for certain airforce launches.

 

Quote

I'm not trying to diminish SpaceX just trying to inject some realism into you, or at least this discussion

Cost per kg to space has been super high until now. This is the main factor, by far, limiting our exploration.

Cheapest non-SpaceX launchers have prices above or close to $5.000 per kg to LEO.

SpaceX Falcon 9 charges around $3.000. Falcon Heavy $1.500.

Starship could, at limit, drop this cost to $15! Even if it's $100, it's a revolution!

 

SpaceX approach is not to revolutionize through new technologies. As all of Musk's companies, this has all to do with process, not technology. Iterative and continuous development. Not some fancy technology.

Even recently, Musk was asked why the Space Shuttle failed. His answer is incredibly simple: it was a design that did not allow iterative development.

Mercury, Gemini and Apollo were all very iterative and successful programs. Shuttle was not.

0

Share this post


Link to post
Share on other sites
8 hours ago, MikeMelga said:

 

Cost per kg to space has been super high until now. This is the main factor, by far, limiting our exploration.

Cheapest non-SpaceX launchers have prices above or close to $5.000 per kg to LEO.

SpaceX Falcon 9 charges around $3.000. Falcon Heavy $1.500.

Starship could, at limit, drop this cost to $15! Even if it's $100, it's a revolution!

 

SpaceX approach is not to revolutionize through new technologies. As all of Musk's companies, this has all to do with process, not technology. Iterative and continuous development. Not some fancy technology.

Even recently, Musk was asked why the Space Shuttle failed. His answer is incredibly simple: it was a design that did not allow iterative development.

Mercury, Gemini and Apollo were all very iterative and successful programs. Shuttle was not.

Again this is all too simplistic

 

Sure Musk has developed a cheaper way to get stuff into space and thats brilliant, as you say the Space shuttle was just too expensive to get weight into space and the basic design lead to an un reliably space craft.

 

But the Space shuttle, could to used for example to re pair the Hubble, Musk has nothing that can do that job - the space shuttle gave the US a unique ability.

 

Its just a case of horse for courses, Falcon gives cheaper access to space while space shuttle gives humans greater freedom to do things in space.

 

There arguments that the Space shuttle was a failure, and it was in many ways, it did provide however the unique set of skills that were important in various situation, ie FALCON  9 does not have a crane or ability to let the astronauts,to go outside the space craft, a lot of has been learned about working in space through the use of the Space shuttle, lets see what would happen, if musks rockets had those capabilities, maybe adding weight to FALCON 9 would make it, not econic, as it was carrying around a lot of dead weight, when just used as a satellite launcher. - just like the space Shuttle.

 

0

Share this post


Link to post
Share on other sites
19 minutes ago, yesterday said:

But the Space shuttle, could to used for example to re pair the Hubble, Musk has nothing that can do that job - the space shuttle gave the US a unique ability.

No, there is a version of the Spaceship with airlock and hangar bay. Same as Shuttle. Actually, the hangar bay (without airlock) will be the most common configuration, to launch satellites. And it allows much larger and heavier volumes. The basic satellite deployer version has a 22 x 8 meter bay, while the shuttle had a 14 x 4.5 meter bay. Payload is up to 250mT vs 22mT on the Shuttle.

https://www.tesmanian.com/blogs/tesmanian-blog/starship-starlink

 

The crew version will have a very wide airlock, because of Mars and Moon missions, so it can perfectly repair the hubble.

Either that, or a cargo version with a robotic arm could just grab the hubble and bring it back for repairs.

 

And the current Dragon 2 was considered for hubble repairs. Technically it can do it with a few modifications. The trunk is big enough to carry lots of materials. Docking is doable. A robotic arm could be placed on the trunk. The only tricky part is there is no airlock, so they would need to purge all the air from the capsule to perform space walks, but that was already done with Gemini program. Either that or they would need to modify one Dragon 2 more extensively.

 

 

0

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0