Luxspace radiation experiment

[EricSmith]

I hadn't been aware of the private mission flown along with Chang'e T1. Luxspace, a European company, put some experiments on that mission, including some radiation sensors. The dose measured on the way to the moon was about 22 rads or so, which is high but nowhere near fatal, so it's another piece of evidence against the "no-one can survive the Van Allen belts" canard. The dose was much higher than Apollo astronauts received, but on the other hand since the experiment was designed to measure radiation it was presumably unshielded, unlike the astronauts. I don't know what the Chang'e trajectory was, but perhaps that may also account for some of the difference.

The original moon.luxspace.lu site isn't responding for me at the moment, but the Internet wayback machine has it:

https://web.archive.org/web/20170629073144/http://moon.luxspace.lu/radiation-experiment/

[bknight]

It would be good to now whether the instruments were shielded, but your speculation may be exactly correct.  Additionally the trajectory should be ascertained.

ETA One of the reasons the web site may not be working is: it is located from the way back machine.

[EricSmith]

It would be good to now whether the instruments were shielded, but your speculation may be exactly correct.

There are some pictures which seem to indicate the instruments were on the outside of the spacecraft. It certainly makes sense that an experiment designed to measure radiation would not itself be shielded from the radiation .

I guess this experiment is unlikely to convince any hardcore moon hoax believers, but it's yet one more (non-NASA) piece of evidence that yes, it is possible for humans to fly through the van Allen belts.

[bknight]

Got a link to these images?

[smartcooky]

http://www.spaceflight101.net/change-5-test-mission-updates.html


http://spaceflight101.com/change/4m-radio-experiment/

Seems obvious to me that the radio sensor would be on the outside of the spacecraft otherwise any data it collected would be compromised by the hull. Putting it on the inside makes about as much sense and putting a rain gauge inside your garage!

[bknight]

http://www.spaceflight101.net/change-5-test-mission-updates.html


http://spaceflight101.com/change/4m-radio-experiment/

Seems obvious to me that the radio sensor would be on the outside of the spacecraft otherwise any data it collected would be compromised by the hull. Putting it on the inside makes about as much sense and putting a rain gauge inside your garage!

That premise seems to be the best option for the monitor. 
Now If we had the trajectory across the VARB, we might be able to obtain a comparison with the Apollo shielded radiation and this.  That might be informative to the Orion project, but it could be old news.

[ka9q]

If you're collecting scientific data, I'd think you'd put the sensors on the outside and have them collect energy and particle type information, not just total counts. Then you could compute the effective dose to people or devices inside whatever spacecraft hull or shielding you happen to have.

[smartcooky]

If you're collecting scientific data, I'd think you'd put the sensors on the outside and have them collect energy and particle type information, not just total counts. Then you could compute the effective dose to people or devices inside whatever spacecraft hull or shielding you happen to have.

If you're going to do that, then why not have a near identical sensor set-up inside the spacecraft. The you can compare actual readings with the calculated expectations... nothing like a bit of empirical data, and it would not come with much of a weight penalty.

[molesworth]

If you're collecting scientific data, I'd think you'd put the sensors on the outside and have them collect energy and particle type information, not just total counts. Then you could compute the effective dose to people or devices inside whatever spacecraft hull or shielding you happen to have.

If you're going to do that, then why not have a near identical sensor set-up inside the spacecraft. The you can compare actual readings with the calculated expectations... nothing like a bit of empirical data, and it would not come with much of a weight penalty.

Although that would only be applicable to the shielding provided by the type of hull construction used in this case.  We can test the actual capabilities of any given type of shielding in experimental setups, and apply any desired levels of radiation to them then measure how much gets through.  (I sometimes think HBs forget we have lots of ways to do experiments on the space environment without actually going into space  )

Plus any increase in mass is best avoided, and extra sensors, electronics, computing etc. will require additional design and testing effort, and will have an effect on reliability.

[raven]

This PDF gives the inclination and orbit at least.

[JayUtah]

Normally you would have multiple sensors on the spacecraft.  Since none would be truly omnidirectional, you want them facing different directions, facing open space.  The scheme of placing them inside the spacecraft structure makes the attenuation uncertain, especially as the spacecraft design evolves.  It also imposes a design constraint that is generally considered to strict for the associated benefit.  That's not to say that deliberate attenuation is not part of the regime.  No one sensor technology has a useful response in the full spectrum of radiation that would be encountered on a cislunar mission.  Hence it's typical to provide an explicit method of attenuation, either by fixed shielding strips of known absorption over the high-intensity sensors, or a mechanism to selectively shield the sensors at different time points.  The former implies multiple sensors for each solid angle of reception.

[bobdude11]

Normally you would have multiple sensors on the spacecraft.  Since none would be truly omnidirectional, you want them facing different directions, facing open space.  The scheme of placing them inside the spacecraft structure makes the attenuation uncertain, especially as the spacecraft design evolves.  It also imposes a design constraint that is generally considered to strict for the associated benefit.  That's not to say that deliberate attenuation is not part of the regime.  No one sensor technology has a useful response in the full spectrum of radiation that would be encountered on a cislunar mission.  Hence it's typical to provide an explicit method of attenuation, either by fixed shielding strips of known absorption over the high-intensity sensors, or a mechanism to selectively shield the sensors at different time points.  The former implies multiple sensors for each solid angle of reception.

This is one of the reasons I am a member here. This is something I thought they would do, but the details were not clear on how or why, precisely. I now have to see if I can recreate something like this in KSP ... Thank you Jay and everyone else for helping me understand space technology better. This is the most amazing part of science for me. I never truly understood how much actually went into designing a rocket and its payload before. All of you are tickling my cerebral cortex at levels I never knew were possible.