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Tiny satellite will use the dark side of the Moon as a shield

vincent-manis 1mo ago
s/dark side/far side/
- ButlerianJihad 1mo ago
  [dead]
- NitpickLawyer 1mo ago
  You're generally correct, but in this particular instance it does actually make sense to call it the dark side. Dark, as in "quiet" from RF interference. Just like some areas on Earth, near radio observatories, are declared "dark" (i.e. everyone tries to avoid using high RF emitting stuff in these regions, even comms satellites avoid it).
  - defrost 1mo ago
    > even comms satellites avoid it. If only ... Starlink is nominally "off' over the RQZ in W.Australia, but still leaking interference from not fully shielded electronics. Starlink Coverage holes (3 years ago) - https://old.reddit.com/r/Starlink/comments/ymm6rv/starlink_coverage_holes/ https://old.reddit.com/r/Starlink/comments/ymm6rv/starlink_c... (July 2025) Starlink satellites disrupting astronomy research in WA's Murchison, study finds - https://www.abc.net.au/news/2025-07-25/starlink-satellites-disrupt-radio-astronomy-skao-telescope-study/105567382 https://www.abc.net.au/news/2025-07-25/starlink-satellites-d...
  - subarctic 1mo ago
    Dark side of the moon = the side opposite the sun, doesn't change here
    - sigio 1mo ago
      It's only facing away from earth, it can face the sun just fine. Rotation is every 4 weeks.
      - subarctic 1mo ago
        That's the far side of the moon
  - deleted 1mo ago
    [deleted]
cozzyd 1mo ago
RFSoCs seem like extreme overkill for this frequency range, though since Xiphos makes a space-grade one, it's not so unreasonable I guess. Alas, I'm working on a competing project that I won't go into detail about :).
zorobo 1mo ago
Would a satellite positioned at Earth Moon L2 be stable enough? It would also need a relay to communicate with earth…
- ericbarrett 1mo ago
  It takes a bit of stationkeeping to stay at L2; like keeping a ball at the top of a low, smooth hill - needs a nudge every now and then. A circular Moon orbit can last years with no fuel use if you pick your inclination correctly. Look up "frozen orbits" (the Moon is lumpy)
- avisser 1mo ago
  > Once CosmoCube’s data is back on Earth Did I miss it or did they fail to explain how that would work? Does it just slowly move around the moon so it gets its 1000 hours of observation, then eventually comes out of the EM shadow? Or is there some final boost that pushes it? Will it crash into the moon eventually?
  - ericbarrett 1mo ago
    It would orbit the moon as a satellite, presumably in a fairly tight and low orbit; the article says a 2 hour period, which is < 100 km above the surface. About half the time it would be on the "far side" and Earth would be blocked by the Moon below it. The other half it would have line-of-sight with Earth and be able to communicate, but also exposed to radio pollution. Presumably the mission designers would hibernate the experiment for this period. It will almost certainly hit the moon one day. The moon has many mascons (mass concentrations, a.k.a. lumps) and destabilizes anything orbiting it over a long period of time. Or even a short period of time: https://en.wikipedia.org/wiki/Apollo_16#Particles_and_Fields_Subsatellite_PFS-2 https://en.wikipedia.org/wiki/Apollo_16#Particles_and_Fields... But an orbit can be chosen to give at least a couple years, which is the mission goal.
    - euroderf 1mo ago
      I remember mentions of mascons during the Apollo missions. They were at the time a bit mysterious but their existence and influence were known.
hn_submit 1mo ago
To be launched within five years?! The Chinese will long before that have produced something similar and returned the data already. The UK has to become a lot more active in getting this project to the launchpad.
RattlesnakeJake 1mo ago
Plot twist, they just bolted one of these onto the back of the cubesat: https://www.goldrecordart.com/product/sku/PFplat1 https://www.goldrecordart.com/product/sku/PFplat1

s/dark side/far side/

ButlerianJihad 1mo ago
[dead]
NitpickLawyer 1mo ago
You're generally correct, but in this particular instance it does actually make sense to call it the dark side. Dark, as in "quiet" from RF interference. Just like some areas on Earth, near radio observatories, are declared "dark" (i.e. everyone tries to avoid using high RF emitting stuff in these regions, even comms satellites avoid it).
- defrost 1mo ago
  > even comms satellites avoid it. If only ... Starlink is nominally "off' over the RQZ in W.Australia, but still leaking interference from not fully shielded electronics. Starlink Coverage holes (3 years ago) - https://old.reddit.com/r/Starlink/comments/ymm6rv/starlink_coverage_holes/ https://old.reddit.com/r/Starlink/comments/ymm6rv/starlink_c... (July 2025) Starlink satellites disrupting astronomy research in WA's Murchison, study finds - https://www.abc.net.au/news/2025-07-25/starlink-satellites-disrupt-radio-astronomy-skao-telescope-study/105567382 https://www.abc.net.au/news/2025-07-25/starlink-satellites-d...
- subarctic 1mo ago
  Dark side of the moon = the side opposite the sun, doesn't change here
  - sigio 1mo ago
    It's only facing away from earth, it can face the sun just fine. Rotation is every 4 weeks.
    - subarctic 1mo ago
      That's the far side of the moon
- deleted 1mo ago
  [deleted]

RFSoCs seem like extreme overkill for this frequency range, though since Xiphos makes a space-grade one, it's not so unreasonable I guess. Alas, I'm working on a competing project that I won't go into detail about :).

zorobo 1mo ago

Would a satellite positioned at Earth Moon L2 be stable enough? It would also need a relay to communicate with earth…

ericbarrett 1mo ago
It takes a bit of stationkeeping to stay at L2; like keeping a ball at the top of a low, smooth hill - needs a nudge every now and then. A circular Moon orbit can last years with no fuel use if you pick your inclination correctly. Look up "frozen orbits" (the Moon is lumpy)
avisser 1mo ago
> Once CosmoCube’s data is back on Earth Did I miss it or did they fail to explain how that would work? Does it just slowly move around the moon so it gets its 1000 hours of observation, then eventually comes out of the EM shadow? Or is there some final boost that pushes it? Will it crash into the moon eventually?
- ericbarrett 1mo ago
  It would orbit the moon as a satellite, presumably in a fairly tight and low orbit; the article says a 2 hour period, which is < 100 km above the surface. About half the time it would be on the "far side" and Earth would be blocked by the Moon below it. The other half it would have line-of-sight with Earth and be able to communicate, but also exposed to radio pollution. Presumably the mission designers would hibernate the experiment for this period. It will almost certainly hit the moon one day. The moon has many mascons (mass concentrations, a.k.a. lumps) and destabilizes anything orbiting it over a long period of time. Or even a short period of time: https://en.wikipedia.org/wiki/Apollo_16#Particles_and_Fields_Subsatellite_PFS-2 https://en.wikipedia.org/wiki/Apollo_16#Particles_and_Fields... But an orbit can be chosen to give at least a couple years, which is the mission goal.
  - euroderf 1mo ago
    I remember mentions of mascons during the Apollo missions. They were at the time a bit mysterious but their existence and influence were known.

hn_submit 1mo ago

To be launched within five years?! The Chinese will long before that have produced something similar and returned the data already. The UK has to become a lot more active in getting this project to the launchpad.

RattlesnakeJake 1mo ago

Plot twist, they just bolted one of these onto the back of the cubesat: https://www.goldrecordart.com/product/sku/PFplat1 https://www.goldrecordart.com/product/sku/PFplat1