Rare exoplanet 40 EP

HD 103949 b

RA 179.5480° · Dec -23.9241° · exoplanet

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Score breakdown

· 3 badges

40 pts · Rare

Rare 46 pts → Epic

In the habitable zone +30
Confirmed exoplanet +5
Sub-Neptune +5

Total score 40

6 more points to reach Epic.

Badges

Confirmed exoplanet · +5
In the habitable zone · +30
Sub-Neptune · +5

Trivia

What makes it special

Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist.

Could we get there?

Verdict. Hopelessly far for any craft humanity can build today.

Getting there

Aboard Voyager 1. ≈ 1.5 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 135 thousand years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 864 years in a starship at a tenth of light speed.
Distance. 86.4 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 1940.

Saying hello

Say hello. A radio message and its reply would take 173 years round-trip.

Standing on it

A year here. A full year lasts just 121 Earth days.

By the numbers

Size. About 3.4× the width of Earth.
Volume. About 37.6 Earths could fit inside it.
Mass. About 11.2× the mass of Earth.
Your weight. You'd weigh about 1.0× your Earth weight standing here.
Temperature. A surprisingly temperate 30°C average.

How we found it

Discovery. Found by Las Campanas Observatory using the radial velocity method.

Properties

density gcc: 1.64
discovery facility: Las Campanas Observatory
discovery method: Radial Velocity
dist ly: 86.4304
eccentricity: 0.19
eq temp k: 302.65
habitable zone: yes
insolation: 1.3983
mass earth: 11.2
name: HD 103949 b
orbital period days: 120.878
radius earth: 3.35
sys num planets: 1

About HD 103949 b

HD 103949 b is a rare exoplanet. It lies about 86.4 light-years from Earth, has an equilibrium temperature near 303 K, spans roughly 3.35 Earth radii and weighs about 11.2 Earth masses.

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

How to see it

Like any astronomical target, HD 103949 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 103949 b is a rare exoplanet

HD 103949 b scores 40 points on Spacedle's rarity scale, which places it in the rare tier. Another 6 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, In the habitable zone and Sub-Neptune — 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.