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Rare pulsar 42 EP

J1602+3901

RA 240.5785° · Dec 39.0172° · pulsar

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Score breakdown

· 2 badges
42 pts · Rare
Rare 50 pts → Epic
  • Pulsar +22
  • Millisecond pulsar +20
Total score 42

8 more points to reach Epic.

Badges

  • Pulsar · +22
  • Millisecond pulsar · +20

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 17.3 — 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.

Find it in the sky

  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around May — 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

dm
17.259
name
J1602+3901
period ms
3.708

Nearby objects

About J1602+3901

J1602+3901 is a rare pulsar. It spins once every 3.708 ms and has a dispersion measure of 17.26 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, J1602+3901 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 J1602+3901 is a rare pulsar

J1602+3901 scores 42 points on Spacedle's rarity scale, which places it in the rare tier. Another 8 points would lift it into a rarer tier.

That score comes from 2 science badges — Pulsar and Millisecond 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.