Does the temperature of the surface of the cupola vary when the ISS is in Earth's shadow, compared to when it is on day side of the Earth? Is it cold to the touch when the ISS in the shadow?


2 Answers 2


The windows of the Cupola are not made of a single pane.

When not shuttered, the Cupola windows present a four layered front to potential impactors: a debris pane, two pressure panes, and an innner scratch pane. The windows are designed to be completely replaceable in the event of severe damage. (1)

There are electrical window heaters and there is an environmental control system with manual temperature adjustment (2).

The window shutters for debris protection are made of several layers of aluminium and Kevlar/Nextel sheets. When not in use "the shutters are closed to protect the glass from micrometeoroids and orbital debris, and to prevent solar radiation from heating up Cupola or to avoid losing heat to space." (3).

The metallic dome of the Cupola has Goldised Kapton Multi-Layer Insulation blankets.

There is also a Thermal Control System with water supplied from Node High Temperature loop.

So the inner surface of the Cupola is neither too hot nor too cold to touch.

enter image description here

enter image description here

The temperature in the Cupola seems to be quite comfortable.

Image sources (4) (5)

  • 1
    $\begingroup$ Excellent information. Did the windows of the space shuttle have a similar construction to moderate the temperature? $\endgroup$
    – Bob516
    Jan 14, 2019 at 17:50
  • 2
    $\begingroup$ @Bob516 yes, the shuttle windows had a multi-pane design and were conditioned by the water coolant loop. How many panes depended on which window you were talking about. $\endgroup$ Jan 14, 2019 at 18:53
  • $\begingroup$ There were no shutters at the Shuttle windows. But of course a multi-pane design was used too. $\endgroup$
    – Uwe
    Jan 14, 2019 at 18:56

In addition to the other answer: the ISS rotates to keep its nadir side (which the cupola is part of) pointed at Earth. This means the cupola is shielded from direct sunlight by the rest of the ISS for most of the daytime half of its orbit.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.