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Rare pulsar 34 EP

J2140-2310A

RA 325.0934° · Dec -23.1802° · pulsar

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Score breakdown

· 2 badges
34 pts · Rare
Rare 50 pts → Epic
  • Pulsar +22
  • Binary pulsar +12
Total score 34

16 more points to reach Epic.

Badges

  • Pulsar · +22
  • Binary pulsar · +12

Trivia

Hard to believe

  • Surface speed. Its equator is moving at roughly 2% of the speed of light. Spin it much faster and it would tear itself apart.

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 25.1 — 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.

Standing on it

  • Why we can see it. We only know about it because its beam happens to sweep across the Earth. Most of the galaxy's pulsars are pointing somewhere else and are invisible to us.

Properties

binary
yes
dm
25.064
name
J2140-2310A
period ms
11.0193

About J2140-2310A

J2140-2310A is a rare pulsar. It spins once every 11.019 ms and has a dispersion measure of 25.06 pc cm⁻³.

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, J2140-2310A 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 J2140-2310A is a rare pulsar

J2140-2310A scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 16 points would lift it into a rarer tier.

That score comes from 2 science badges — 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.