Rare exoplanet 41 EP

HAT-P-8 b

RA 343.0415° · Dec 35.4472° · exoplanet

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Score breakdown

· 5 badges

41 pts · Rare

Rare 46 pts → Epic

Lava world +14
Hot Jupiter +10
Blasted by starlight +8
Confirmed exoplanet +5
Gas giant +4

Total score 41

5 more points to reach Epic.

Badges

Confirmed exoplanet · +5
Gas giant · +4
Hot Jupiter · +10
Lava world · +14
Blasted by starlight · +8

Trivia

What makes it special

Lava world. Its surface is likely an ocean of molten rock.

Could we get there?

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

Getting there

Aboard Voyager 1. ≈ 12.1 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 1.1 million years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 6900 years in a starship at a tenth of light speed.
Distance. 690 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 1336.

Saying hello

Say hello. A radio message and its reply would take 1380 years round-trip.

Standing on it

A year here. A full year lasts just 3.1 Earth days.

By the numbers

Size. About 15.7× the width of Earth.
Volume. About 3864 Earths could fit inside it.
Mass. Roughly 407× Earth's mass — about 1.3 Jupiters.
Your weight. You'd weigh about 1.7× your Earth weight standing here.
Density. Less dense than water — drop it in a big enough ocean and it would float.
Temperature. Around 1440°C — hotter than a self-cleaning oven.

How we found it

Discovery. Found by HATNet using the transit method.

Properties

density gcc: 0.6856
discovery facility: HATNet
discovery method: Transit
dist ly: 689.9928
eccentricity: 0
eq temp k: 1713
insolation: 1519.9645
mass earth: 406.8224
name: HAT-P-8 b
orbital period days: 3.0763
radius earth: 15.6926
sys num planets: 1

About HAT-P-8 b

HAT-P-8 b is a rare exoplanet. It lies about 690 light-years from Earth, has an equilibrium temperature near 1,713 K, spans roughly 15.69 Earth radii and weighs about 406.82 Earth masses.

Its surface is likely an ocean of molten rock.

How to see it

Like any astronomical target, HAT-P-8 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 HAT-P-8 b is a rare exoplanet

HAT-P-8 b scores 41 points on Spacedle's rarity scale, which places it in the rare tier. Another 5 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Lava world and Blasted by starlight — 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.