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Epic pulsar 54 EP

J2129-5721

RA 322.3449° · Dec -57.3540° · pulsar

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Score breakdown

· 3 badges
54 pts · Epic
Epic 78 pts → Anomaly
  • Pulsar +22
  • Millisecond pulsar +20
  • Binary pulsar +12
Total score 54

24 more points to reach Anomaly.

Badges

  • Pulsar · +22
  • Millisecond pulsar · +20
  • Binary pulsar · +12

Trivia

Hard to believe

  • Surface speed. Its equator is moving at roughly 6% of the speed of light. Spin it much faster and it would tear itself apart.
  • Better than a clock. Millisecond pulsars keep time so well that a network of them is being used as a galaxy-sized detector for gravitational waves — more stable over decades than the best atomic clocks.

Handle with care

  • Its gravity. Surface gravity is around 190 billion times Earth's. A fall of one metre would end at roughly a tenth of the speed of light.

What it actually is

  • What it is. The collapsed core of a star that exploded: about one and a half Suns of matter crushed into a ball the size of a city, held up only by the refusal of neutrons to be squeezed further.
  • Reading the fog. Its dispersion measure is 31.8 — a count of the free electrons in every column of space between here and there. Those electrons slow the low-frequency pulses more than the high ones, and that lag is how its distance is worked out.
  • It has a partner. It orbits a companion star, and because its pulses are such a precise clock the orbit can be traced to extraordinary accuracy. A binary pulsar is how gravitational waves were first proven to be real, decades before one was directly detected.

Find it in the sky

  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around August — that's when to go looking.

Properties

binary
yes
bsurf
282086460.6
dm
31.848
name
J2129-5721
period ms
3.7263

Nearby objects

About J2129-5721

J2129-5721 is an epic pulsar. It spins once every 3.726 ms, has a dispersion measure of 31.85 pc cm⁻³ and carries a surface magnetic field around 282,086,461 G.

The collapsed core of a star that exploded: about one and a half Suns of matter crushed into a ball the size of a city, held up only by the refusal of neutrons to be squeezed further.

How to see it

Like any astronomical target, J2129-5721 is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.

Why J2129-5721 is an epic pulsar

J2129-5721 scores 54 points on Spacedle's rarity scale, which places it in the epic tier. Another 24 points would lift it into a rarer tier.

That score comes from 3 science badges — Pulsar, Millisecond pulsar and Binary pulsar — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.