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Entering orbit…
Habitability
5/ 100
Uninhabitable

PSR 123+11A b

0

Rocky Terrestrial

None Activity
Why is this a Rocky Terrestrial?Your planet is dominated by silicate (50.0%) and iron (50.0%) content, forming a rocky terrestrial body.
Rocky terrestrial planets are primarily composed of silicate rocks and metals. They're the most common type of small planet in the universe.
Classification Criteria:
✓ Silicon: 50.0% + Iron: 50.0% + Magnesium: 0.0%✓ Mass: 0.3x Earth (terrestrial range)
Habitability ScoreUninhabitable
5
Contributing Factors
water0
No water - the recipe has no hydrogen and oxygen to form it
geology30
Geologically dead - no nutrient recycling
rotation100
Optimal rotation period - balanced day/night cycle, moderate weather, and good heat distribution
Organic Chemistry20
Limited organic chemistry potential
atmosphere10
No atmosphere - exposed to radiation and temperature extremes
temperature100
Optimal temperature range for liquid water and life
magnetic Field30
No magnetic field - vulnerable to solar radiation — but the pulsar's beams bathe this orbit in hard X-rays

Physical Properties

Mass
0.30x Earth (1.79e+24 kg)
Radius
0.67x Earth (4,265 km)
This planet: 0.67× Earth radiusEarth: 1× (baseline)
Surface Gravity
0.67x Earth (6.6 m/s²)
Surface Temperature
278 K (5 °C / 41 °F)
Rotation Period
24.0 hours/day
This planet: 24 h/dayEarth: 24 h/day

Orbital Environment

Star Type
NS-type (Neutron Star)
Distance from Star
0.10 AU (15 million km)
Orbital Period
10 days
Time Dilation
Clocks run 6.5 seconds per year slower than deep space — about 9 minutes over a lifetime

Atmosphere

Minimal or none

Elemental Composition

Fe - Iron
50.0%
Si - Silicon
50.0%

Surface Characteristics

Rocky surface with impact craters, possible volcanic features

Closest Real Exoplanet

TRAPPIST-1 d92% similar
Orbiting TRAPPIST-1
YoursTRAPPIST-1 d
Mass0.30 × Earth0.39 × Earth
Radius0.73 × Earth0.79 × Earth
Density (composition)4.22 g/cm³4.37 g/cm³
Temperature278.0 K286.0 K
Starlight received1.00 × Earth1.11 × Earth
Star temperature— 2,566 K
Matched on physical properties only — but pulsar planets are real: the first exoplanets ever confirmed (PSR B1257+12, 1992) orbit a neutron star.Discovered 2016 via transit · 40 light-years awaySource: NASA Exoplanet Archive
Surface views from three worlds: rocky ground under a ringed sky, a cloud deck, and a lit desert

New: Stand on Your World 🏔️

Every planet you build can now be seen from the ground. The terrain, the color of the sky, the weather and what hangs overhead are all read from the same numbers that shape the globe — so a thin-aired world gives you sunlit rock under a near-black sky crowded with stars, a runaway greenhouse seals you under an unbroken sulfur lid, and a gas giant leaves you in the cloud tops with nothing solid beneath you at all. If one of your moons wandered inside the Roche limit, what is left of it arcs overhead as rings.

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