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I watched a video called Powers of Ten made in the 70s. It starts from a view of an area in Chicago and moves the "camera" away from the ground towards the space. At 3m15s of the video, the center of the "camera" points to the Sculptor constellation area. In particular, the center is close to Alpha Sculptoris, whose declination is around -29°.

However, the latitude of Chicago is around 42°N, so the star we "see" in the opposite direction should have declination -42° (Thanks to JohnHoltz for correction). So it seems that the center should lie in the Phoenix region instead.

Did the video's author make a mistake, or am I missing something?

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  • $\begingroup$ The star above 42 N latitude has a declination of +42. The star underneath has a declination of -42. That's only a small difference from your calculation, so that does not explain the difference in the video. $\endgroup$
    – JohnHoltz
    Jul 2 at 0:20
  • $\begingroup$ @JohnHoltz Oh, you're right. I made a mistake. 42 is closer to 29 indeed. $\endgroup$
    – Elon
    Jul 2 at 0:38
  • $\begingroup$ I saw the original Powers of Ten video on public TV I think back in the 1970's and also enjoyed the book. This reminds me of the slightly rant-like enthusiasm of Dr. Neil deGrasse Tyson - Titanic 3D and Cameron "Wrong Sky" $\endgroup$
    – uhoh
    Jul 2 at 10:29
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    $\begingroup$ @uhoh That’s an interesting story! $\endgroup$
    – Elon
    Jul 3 at 2:44

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I initially thought it was a switch to a view from the north ecliptic pole +66 deg declination but Got it: The zoom direction changed from straight above Chicago to a view point from the galactic north pole. Alpha Sculptoris is near the south galactic pole at galactic coordinates 268 deg long -87 deg (lat). Thus explains why planet orbits look elongated and at 4:10 we are perpendicular to the Milky Way. Staring at the background stars the switch looks like it happened early before reaching moon. You can see Alpha Sculptoris at that point. Note at 3:15 narration says "southern constellations as they appear from far side of earth which is a bit misleading.

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  • $\begingroup$ So there are (at least) three view directions in the video: 1. perpendicular to the ground of Chicago. 2. perpendicular to the ecliptic. 3. perpendicular to the galactic disk of the Milky Way. $\endgroup$
    – Elon
    Jul 6 at 5:07
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    $\begingroup$ I think it skipped perpendicular to ecliptic because the orbits look elongated. They are in reality very nearly round. Staring at the background stars; you can pick alpha Sculptoris as being just behind the earth even before the moon's orbit appears. So I think the video switched early on from perpendicular to Chicago to the galactic axis very early on. $\endgroup$ Jul 6 at 6:33

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