Search results
Results From The WOW.Com Content Network
First, the positions of the south and north celestial poles appear to move in circles against the space-fixed backdrop of stars, completing one circuit in approximately 26,000 years. Thus, while today the star Polaris lies approximately at the north celestial pole, this will change over time, and other stars will become the "north star". [3]
A navigator on watch does not always have a corrected compass available with which to give an accurate bearing. If available, the bearing might not be numerate. Therefore, every forty-five degrees of direction from north on the compass was divided into four 'points'. Thus, 32 points of 11.25° each makes a circle of 360°.
The apparent motion of Polaris towards and, in the future, away from the celestial pole, is due to the precession of the equinoxes. [35] The celestial pole will move away from α UMi after the 21st century, passing close by Gamma Cephei by about the 41st century, moving towards Deneb by about the 91st century. [citation needed]
The Polaris Flare is a filamentous gas cloud in the Milky Way which is seen in the sky in the region of the constellation Ursa Minor and around the star Polaris. [2] [4] The area on the sky is estimated at 50 square degrees. [1] The range is approximately 500 light years. [2]
The geographic poles are defined by the points on the surface of Earth that are intersected by the axis of rotation. The pole shift hypothesis describes a change in location of these poles with respect to the underlying surface – a phenomenon distinct from the changes in axial orientation with respect to the plane of the ecliptic that are caused by precession and nutation, and is an ...
A magnetic compass points to magnetic north, not geographic (true) north. Compasses of the style commonly used for hiking (i.e., baseplate or protractor compass) utilize a dial or bezel which rotates 360 degrees and is independent of the magnetic needle. To manually establish a declination for true north, the bezel is rotated until the desired ...
Thus, northern circumpolar stars move counterclockwise around Polaris, the north pole star. At the North Pole, the cardinal directions do not apply to diurnal motion. Within the circumpolar circle, all the stars move simply rightward, or looking directly overhead, counterclockwise around the zenith, where Polaris is.
A 180 degree straight-twin engine has a secondary imbalance (similar to an inline-four engine); however, the lower reciprocating mass means that this often does not require treatment. A 180° crankshaft engine suffers fewer pumping losses than a 360° twin, because displacement of the crankcase is relatively unchanged as the pistons move.