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If I initiate a climb just after watching the sun go down below the horizon, how fast would I have to climb in order to watch the sun come back up, so that I could then level off and watch the sunset for a second time?

I've Googled the answer, and several different articles have said that I'd need a minimum rate of climb of 5000 ft/min. However, I've also read several articles that said you can do the same thing in the Burj Khalifa's elevator, and it maxes out at 2000 ft/min. So, which of these is correct, if any?

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    $\begingroup$ If you go in the direction of the sun you will also gain on it. So you need to consider forward speed as well as climb rate. You can have a pretty low (or even no) climb rate if you are moving forward fast enough. $\endgroup$
    – Dave
    Mar 20, 2019 at 2:17
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    $\begingroup$ I think this question would be a much better fit for math.stackexchange.com, actually. I recommend having it moved there. To do that, click on the word "flag" at the bottom of your question, click "in need of moderator intervention", and explain that you'd like the question to be moved to math.stackexchange.com. The reason I say this is that the answer is going to involve a lot of math, and essentially nothing related to aviation. $\endgroup$ Mar 20, 2019 at 2:52
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    $\begingroup$ It is non-linear, the higher above the ground you get the faster you have to climb, see here: blog.xkcd.com/2009/04/06/a-date-idea-analyzed $\endgroup$
    – OSUZorba
    Mar 20, 2019 at 3:12
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    $\begingroup$ I do it quite often, trying to catch 'the green ray'. This afternoon, for example, I have seen the sun setting twice. I fly a gyro, and the sun sets behind mountains 30-35 km. away. $\endgroup$
    – xxavier
    Mar 20, 2019 at 20:16
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    $\begingroup$ Can't imagine why this is closed. Anyway, even in a lowly Cessna 152 I've made the last bit of the setting sun disappear, then re-appear, then disappear again, etc, multiple times as I flew westward toward a distant mountain range, while alternately flying level and climbing. Looking for that "green rim" / "green flash', sometimes successfully. Latitude was about 45 degrees north. $\endgroup$ Jun 22, 2021 at 13:03

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Concorde did something similar: it would take off from London at sunset and then fly West faster than the Earth's rotation, so you would get a sunrise in the West on board.

This capability was also used for solar eclipse flights. While a solar eclipse lasts no more than 8 minutes on the ground, Concorde was able to stay in the Moon's shadow for 74 minutes.

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This question has merit in that it touches on weather and the earths rotation, which are certainly aviation related. Amazingly, at the equator, the earth rotates at around 1000 mph, with the atmosphere going right along with it. It will more difficult to "chase" the sun here as the ground and the air (with minor variation) are moving faster than the speed of sound.
You can climb for a second sunset factoring in the rate the ground is "sinking" from the horizon from the earths rotation.

However, at higher latitudes, the "chase" will be easier. You can not only climb for the second sunset, but also chase it to a point where it will re-appear on the horizon if your plane is faster than the earths rotation at that latitude. So, the solution is how fast you can climb minus the rate your location is "sinking" from the horizon (angle to the horizon), and the suns "speed" minus the aircraft ground speed.

Because the earth is curved, the "sink rate" is not linear over time (6 hours later the entire earth is between you and the sun). So you may not wish to try it too long after the sun sets!

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  • $\begingroup$ Factor in the time of year as well because this affects the angle and rate the sun sets... $\endgroup$ Mar 20, 2019 at 22:32
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“Is it possible to see the same sunset twice, from the same aircraft”.

Well, it is possible, to see two sunrise’s on the same flight, although these are not the same sunrise’s:

See: Chasing the double sunrise

and: The double sunrise

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