← Back to dex
Epic exoplanet 62 EP

HD 4203 b

RA 11.1722° · Dec 20.4484° · exoplanet

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 6 badges
62 pts · Epic
Epic 78 pts → Anomaly
  • In the habitable zone +30
  • Eccentric orbit +9
  • Orbits a Sun-like star +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 62

16 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Gas giant · +4
  • Eccentric orbit · +9
  • Multi-planet system · +6
  • Orbits a Sun-like star · +8

Trivia

What makes it special

  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.

What it actually is

  • What it is made of. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.
  • What the zone means. The habitable zone is only about temperature: it is the band where liquid water could survive on a surface. It is a promising address, not evidence of anything living.
  • Crowded system. One of at least 2 planets orbiting its star.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 8.7 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • 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 October — that's when to go looking.

Properties

density gcc
1.66
diameter km
169657.46
discovery facility
W. M. Keck Observatory
discovery method
Radial Velocity
discovery year
2001
dist ly
265.4241
eccentricity
0.52
eq temp k
297.28
habitable zone
yes
host star teff
5596
insolation
1.4338
mag
8.7
mass earth
708.7609
name
HD 4203 b
orbital period days
431.88
radius earth
13.3
semi major au
1.17
spect
G5
sys num planets
2
sys num stars
1

About HD 4203 b

HD 4203 b is an epic exoplanet. It lies about 265.4 light-years from Earth, shines at apparent magnitude 8.7, has spectral type G5 and has an equilibrium temperature near 297 K.

Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.

How to see it

At apparent magnitude 8.7, it is an easy target for binoculars.

Like any astronomical target, HD 4203 b 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 HD 4203 b is an epic exoplanet

HD 4203 b scores 62 points on Spacedle's rarity scale, which places it in the epic tier. Another 16 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, In the habitable zone, Gas giant, Eccentric orbit, Multi-planet system and Orbits a Sun-like star — 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.