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To "outrace the Sun" (or rather the earth) in Arctic latitudes, one can go much more slowly. Above Novaya Zemlya, on the 77th parallel, a plane doing about 450 km. p.h. would cover as much as a definite point on the surface of the globe would cover in an identical space of time in the process of the earth's axial rotation. If you were flying in such a plane you would see the sun suspended in immobility. It would never set, provided, of course, that your plane was moving in the proper direction.

What does outracing the sun,earth mean?

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    $\begingroup$ Can you ask a more specific question than "what does this mean", please? At present, it's unclear what you don't understand and what you want to know, so answerers have to guess what the problem is. Also, if you quote something, please add the source from where you quoted it. $\endgroup$
    – ACuriousMind ♦
    Commented Apr 23, 2017 at 10:00
  • $\begingroup$ Quoted from Physics for Entertainment by L.Lamm $\endgroup$
    – Vishruth
    Commented Apr 24, 2017 at 15:07
  • $\begingroup$ This edit doesn't make the question any more clear. You also should edit the source of the quote into the question itself. You know how the sun revolves around the Earth? They are talking about the speed you would need to move over the surface so that the sun is revolving the same speed as you. In that case the sun wouldn't seem to move in the sky. $\endgroup$
    – JMac
    Commented Apr 24, 2017 at 16:00
  • $\begingroup$ You are free to edit,delete the question if you feel its unclear. $\endgroup$
    – Vishruth
    Commented Apr 25, 2017 at 11:57

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We know the earth is an (approximate) sphere, with a diameter of about $12,742 km$. That gives it a circumference at the equator of just over $40,000 km$.

As the earth makes a complete revolution in 24 hours, a point on the equator is travelling about $40000/24=1660 km/h$. If you wanted to keep the sun in the same position in the sky, you need to travel at the same speed but in the opposite direction, i.e. $1,660 km/h$, towards the west.

As you move away from the equator, you travel a smaller and smaller distance per 24 hours, and you can travel slower to keep the sun steady. At the poles, you don't need to travel at all - all that's needed is to turn around completely every 24 hours.

Novaya Zemlya is at $73° 42'$ north (or $73.7°$). Hence its speed around the axis is $$1660*cos(73.7)= 465 km/h$$ If your plane is going $465 km/h$ westwards at the latitude of Novaya Zemlya, you will see the sun stand still in the sky. Your figure of $77°$ for latitude is correct for the very northern tip of the island, but that would give a speed of only $375 km/h$.

This effect is easily noticed when travelling in an airplane. Travelling towards the west, the day seems much longer than when travelling eastwards. In the days of the Concorde, which flew at $2,180 km/h$, westward travel even overtook the sun, so that the pilots were able to see the sun rise in the west if they were flying westwards at the right time of day.

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