What range of azimuth would include all the locations on the horizon at which stars can rise?

Answer 1

Tricky question when you think about it.

There's a patch of stars around the celestial pole that are "circumpolar" ... a kind of

misleading term that's used to indicate that they don't rise or set, they're always up.

The angular radius of the circumpolar region (the altitude of the pole in your sky)

is equal to your latitude, and it's also the range of azimuth on your northern or

southern horizon where no stars rise or set.

So we're going to say this: Stars can rise or set anywhere on the horizon ... at

azimuths from zero to 360 degrees,

excepta space either side of the sub-polar point on your horizon (north horizon in the

northern hemisphere, south horizon in the Southern Hemisphere) equal to your

latitude, on each side.

So, in the northern hemisphere, the answer is:

All azimuths between (your latitude) and (360 minus your latitude).

In the southern hemisphere, the answer is:

All azimuths between (zero) and (180 minus your latitude), or between (180 plus your latitude) and (360).

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Epilogue:

Looking back over this presentation, the same contributor is suddenly

overcome by a deep conviction that it's baloney. But I'm tired. Maybe

I'll come back and fix it. In the meantime, don't use it on a bar bet.

Answer 2

The range of azimuth for stars rising on the horizon is approximately 90 degrees to 270 degrees. This covers the eastern half of the horizon where stars rise as the Earth rotates.