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The timeline in the press kit for the upcoming CRS-9 SpaceX launch says at about 11 minutes after launch, "Dragon's solar arrays deploy", and at 2 hours 19 minutes, "Dragon's Guidance, Navigation and Control bay door opens".

I can imagine that cameras for guidance would be protected behind a door, but it sounds like there is a lot more there!

What all is there in the Guidance, Navigation and Control bay that would need to be exposed to space after the door opens?

edit: I found some pics on line - is this the door in question? The gold structure on the inside surface of the door is different in the two pics - but they both look vaguely antenna-like. What are those?

enter image description here

Above: from SpaceX - click for full size.

enter image description here

Above: from SpaceX DragonLab Fact Sheet - click for full size, or just go see the PDF.

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    $\begingroup$ The image from the fact sheet is an artist's impression predating the first Dragon launch and does not show the actual Dragon 1 configuration. $\endgroup$ – Hobbes Jul 18 '16 at 8:07
  • $\begingroup$ @Hobbes think I should pull it out then, or leave it there since your comment clarifies? $\endgroup$ – uhoh Jul 18 '16 at 15:14
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From the SpaceX site:

The sealed equipment bay on the forward side of Dragon (shown with the bay door open in the photo below) contains state-of-the-art sensors essential to Dragon Guidance, Navigation, and Control (GNC). Optical sensors, laser-based range sensors, and inertial sensors are used during Dragon free-flight and approach to the space station.

Redundant sensors are also connected to the fault-tolerant avionics suite, increasing the system’s safety and reliability. The sensors are concealed by the GNC bay door, which opens on ascent to allow sensors to take measurements and closes to protect them during reentry.

The gray circle is the Canadarm grapple fixture.

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  • $\begingroup$ OK, "optical sensors" might include cameras and other things with lenses and windows that need to be protected, as would laser-based range sensors. But why would "inertial sensors" need to be behind a door and exposed to space? I'd think that inertial sensors could be placed in a wide variety of spaces within the volume of the spacecraft. I'm thinking that they would be accelerometers and gyros, mostly MEMs chips or fiber optic (optical gyro) based. Why the need to be behind a door for those guys? $\endgroup$ – uhoh Jul 18 '16 at 13:44
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    $\begingroup$ they're not necessarily saying the inertial sensors are in that bay, just that the GNC system contains inertial sensors. $\endgroup$ – Hobbes Jul 18 '16 at 13:47
  • $\begingroup$ Oh, got it - thanks! And the large gay circle with the three-pointed star thingy that seems to dominate the area, is that some kind of antenna, or something to connect to the Canadarm? I can't figure out what it is. $\endgroup$ – uhoh Jul 18 '16 at 13:49
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    $\begingroup$ @uhoh more on grapple fixtures space.stackexchange.com/questions/14973/… $\endgroup$ – Organic Marble Jul 18 '16 at 15:16
  • $\begingroup$ @OrganicMarble Those are some beautiful photos, of even more beautiful engineering! $\endgroup$ – uhoh Jul 18 '16 at 15:29
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Star sensor, DragonEye, and the CanadArm grapple fixture.

In the first picture in the question, the plate with a triangle/pyramid like structure if the grapple fixture for the CanadArm.

The second image is just art and I do not think entirely accurate.

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  • $\begingroup$ Ah, this stuff. Thanks! $\endgroup$ – uhoh Jul 18 '16 at 4:46
  • $\begingroup$ I've modified the question - am I mixing up two different doors? $\endgroup$ – uhoh Jul 18 '16 at 5:22

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