ESA's Euclid Space 'Scope Is De-Icing Now -- On A Schedule...

While being assembled on Earth, it is always the case that even with lots of dry rooming, and careful prep, space 'scopes (and spacecraft, more generally), retain at least a tiny fraction of the water molecules naturally present in the air, in between the layers of the various sub-assemblies.

And since space is. . . a vast vacuum -- it sucks those little water molecules (from the inside, outward), toward the surfaces of the 'scope -- and then, in the near negative 290 degrees, they tend to freeze onto the nearest flatish surfaces. And the mirrors are a very large -- and nearly flat -- natural collecting surface. So it is that Euclid will now have to de-ice the mirrors, with its pre-installed heaters, from time to time. Heating however, in deep space. . . amounts to raising the temp to only minus three or so.

But that will be enough for the water to detach and float away. . . it is believed. Here's that story, from ESA.int:

. . .A few layers of water ice -- about the width of a strand of DNA -- are starting to impact Euclid’s vision; a common issue for spacecraft in the freezing cold of space, but a potential problem for this highly sensitive mission that requires remarkable precision to investigate the nature of the dark Universe. After months of research, Euclid teams across Europe are now testing a newly designed procedure to de-ice the mission's optics.

If successful, the operations will validate the mission teams’ plan to keep Euclid’s optical system as ice-free as possible for the rest of its life in orbit. . . .

What a time to be alive. . . and "awake" -- pushing back against the dark of ignorance, is the bright face of mirrored space science. Or. . . "woke", if you prefer. Smile. . . .

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