Final answer:
The compass needle's north pole points toward Earth's magnetic north, which is actually the magnetic south pole, near the geographic North Pole. If Earth's magnetic north were aligned perfectly with the geographic north, the orientation of a compass needle would not change as you fly due west along the equator. However, magnetic north and geographic north are not perfectly aligned, and magnetic poles can shift over time.
Step-by-step explanation:
The compass needle's north pole is actually attracted to Earth's magnetic north pole, which is located near Earth's geographic North Pole. However, Earth's magnetic north is technically the magnetic south pole of an equivalent bar magnet, given that magnetic field lines travel from north to south. This means that the compass needle, which points towards the so-called magnetic north, is actually aligning with Earth's magnetic south pole.
Hans Oersted's discovery that electric currents generate magnetic fields underpins the principle on which compasses operate. If we simplify the Earth's magnetic field and assume the magnetic north pole overlaps with the geographic north pole, a compass will show the north pole of its needle pointing 'northwards' when you're at the equator. As you travel due west, the orientation of the compass needle should not change significantly as long as the magnetic north remains aligned with the geographic north.
However, it's important to remember that Earth's magnetic field is not constant and the alignment of magnetic and geographic poles is not perfect. Also, the magnetic poles have historically changed positions. The needle of a magnetic compass does not point to the true north but to the magnetic north, which is close to but not exactly the same as true north.