Another drawback that HTP has is its rather poor freezing point, as it
melts only just below the freezing point of water at atmospheric pressure,
which is fine for Earth applications but rather annoying for a deep space
mission.
I mean, spacecraft obviously tend to have good thermal management as
batteries and other electronics have rather narrow working ranges, but
having a freezing point that's 50K higher than your hydrazines does seem a
bit challenging from a thermal standpoint. Especially as the renders they
have shown feature nice, shiny white probes, which loses you even more heat.
They probably thought that all through and have done proper thermal
management, but still, it's kinda surprising to go with peroxide when there
are (generally speaking) better alternatives available.
