APEIRA ASTRA
PULSAR LIGHTHOUSE COSMOS INSTRUMENT 05 · ROTATING NEUTRON STAR

GEOMETRY OF A COSMIC CLOCK

A beam we see
only when it
finds us.

A pulsar is a rapidly rotating, highly magnetized neutron star. Its radiation is concentrated into beams associated with the magnetic poles. A pulse arrives when a beam sweeps across our line of sight.

rotation axis magnetic axis observer sightline
BEAM OFF SIGHTLINE
SPIN FREQUENCY
30.30 Hz
LIGHT-CYLINDER RADIUS
1,575 km
DIPOLE-FIELD ESTIMATE
3.77 × 10¹² G
CHARACTERISTIC AGE
1,245 yr
SPIN-DOWN POWER
4.63 × 10³¹ W

Derived values use standard vacuum magnetic-dipole estimates with I = 10³⁸ kg·m². They are useful diagnostics, not complete magnetosphere solutions.

SYNTHETIC PULSE PROFILEBrightness versus rotational phase

ONE BEAM INTERSECTS THE OBSERVER

0.00.250.50.751.0 PHASE

WHAT THE MODEL MEANS

The pulse is geometry,
not a star switching on and off.

Rotation and magnetic axes

The cyan axis is the rotation axis. The violet axis is the idealized dipole magnetic axis, tilted by α. The field and emission cones corotate. The orange line is a distant observer at inclination ζ.

The light cylinder

The transparent cylinder marks RLC = cP/2π, where rigid corotation would reach light speed. Its displayed radius is visually compressed; the numeric value is physical.

Scientific limits

Real pulsar magnetospheres are plasma-filled, time-dependent, and not pure vacuum dipoles. Beam shapes, radio-emission altitude, field sweepback, general relativity, glitches, and multipolar fields are omitted here.

DRAG OR ZOOM OVER THE PULSAR · SCROLL ELSEWHERE TO READ · CHANGE α AND ζ TO FIND THE BEAM