Rare exoplanet 39 EP

HD 100777 b

RA 173.9646° · Dec -4.7555° · exoplanet

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Score breakdown

· 3 badges

39 pts · Rare

Rare 46 pts → Epic

In the habitable zone +30
Confirmed exoplanet +5
Gas giant +4

Total score 39

7 more points to reach Epic.

Badges

Confirmed exoplanet · +5
In the habitable zone · +30
Gas giant · +4

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. ≈ 2.8 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 252.3 thousand years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 1616 years in a starship at a tenth of light speed.
Distance. 162 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 1864.

Saying hello

Say hello. A radio message and its reply would take 323 years round-trip.

Standing on it

A year here. A full year lasts just 383 Earth days.

By the numbers

Size. About 13.7× the width of Earth.
Volume. About 2571 Earths could fit inside it.
Mass. Roughly 391× Earth's mass — about 1.2 Jupiters.
Your weight. You'd weigh about 2.1× your Earth weight standing here.
Density. Less dense than water — drop it in a big enough ocean and it would float.
Temperature. A surprisingly temperate -9°C average.

How we found it

Discovery. Found by La Silla Observatory using the radial velocity method.

Properties

density gcc: 0.835
discovery facility: La Silla Observatory
discovery method: Radial Velocity
dist ly: 161.5568
eccentricity: 0.38
eq temp k: 264.28
habitable zone: yes
insolation: 0.9345
mass earth: 390.9289
name: HD 100777 b
orbital period days: 383
radius earth: 13.7
sys num planets: 1

About HD 100777 b

HD 100777 b is a rare exoplanet. It lies about 161.6 light-years from Earth, has an equilibrium temperature near 264 K, spans roughly 13.7 Earth radii and weighs about 390.93 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 100777 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 100777 b is a rare exoplanet

HD 100777 b scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 7 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, In the habitable zone and Gas giant — 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.