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Few_Carpenter_9185 t1_iroezsi wrote

Reply to comment by astro_pettit in Many people have asked me if deep space photos can be captured from the ISS. This image I took aboard of the Large Magellanic Cloud shows how! More details in comments. by astro_pettit

That is great! And the raw images must have been very good to only need a stack of four to produce that final result.

I believe I understand what the ISS maintaining "XPOP or solar inertial attitude" is, and how a constant orientation to the sun produces only about 1°/day of change in the visible starfield through a specific viewport. Because the only significant change is one additional day of movement of the Earth in its around the Sun.

An "LVLH" Earth fixed orientation for the ISS instead, would cause almost 2° of movement in a 30 second exposure. Assuming a 91 minute 30 second orbital period rough average between boosts.The LMC covers about 10° of the sky, so... Smeeeeearrr.

Is there any additional equipment that held the camera steady during the 1/2 minute exposures? And are there challenges with internal reflections in the viewport?

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astro_pettit OP t1_iroyh3p wrote

you got the math right; ISS now pitches at 4 degrees per minute, 16X faster than Sidereal rates.

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