Steve VanSickle writes:
> Yep, you would need to use something more durable than a CD-ROM. I think
Patterned gold foil or Pt/Ir foil looks like a fairly good substitute. With electrochemical proximal probe you can create any number of pits you like.
> that preserved DNA of a wide range of creatures would be nice as part of
> the "message". And designing a radio that could transmit after 50,000
> years is an interesting, but I think doable, challenge. Anyone have ideas
> on how to do *that*?
You already have good vacuum, why not using a primitive triode-driven resonance coil as a simple beakon? Monocrystalline Si, if protected by sublimable ice layer should be able to survive that long.