Epic exoplanet 51 EP

HAT-P-4 b

RA 229.9912° · Dec 36.2295° · exoplanet

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Score breakdown

· 6 badges

51 pts · Epic

Epic 68 pts → Anomaly

Lava world +14
Hot Jupiter +10
Distant (>1000 ly) +10
Blasted by starlight +8
Confirmed exoplanet +5
Gas giant +4

Total score 51

17 more points to reach Anomaly.

Badges

Confirmed exoplanet · +5
Gas giant · +4
Hot Jupiter · +10
Lava world · +14
Blasted by starlight · +8
Distant (>1000 ly) · +10

Trivia

What makes it special

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

Could we get there?

Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

Aboard Voyager 1. ≈ 18.4 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 1.6 million years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 10.5 thousand years in a starship at a tenth of light speed.
Distance. 1045 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 981.

Saying hello

Say hello. A radio message and its reply would take 2090 years round-trip.

Standing on it

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

By the numbers

Size. About 14.3× the width of Earth.
Volume. About 2912 Earths could fit inside it.
Mass. Roughly 213× Earth's mass — about 0.7 Jupiters.
Your weight. You'd weigh about 1.0× your Earth weight standing here.
Density. Less dense than water — drop it in a big enough ocean and it would float.
Temperature. Around 1413°C — hotter than a self-cleaning oven.

How we found it

Discovery. Found by HATNet using the transit method.

Properties

density gcc: 0.403
discovery facility: HATNet
discovery method: Transit
dist ly: 1045.1702
eccentricity: 0
eq temp k: 1686
insolation: 1438
mass earth: 213.255
name: HAT-P-4 b
orbital period days: 3.0565
radius earth: 14.28
sys num planets: 1

About HAT-P-4 b

HAT-P-4 b is an epic exoplanet. It lies about 1,045.2 light-years from Earth, has an equilibrium temperature near 1,686 K, spans roughly 14.28 Earth radii and weighs about 213.25 Earth masses.

Its surface is likely an ocean of molten rock.

How to see it

Like any astronomical target, HAT-P-4 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-4 b is an epic exoplanet

HAT-P-4 b scores 51 points on Spacedle's rarity scale, which places it in the epic tier. Another 17 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Lava world, Blasted by starlight and Distant (>1000 ly) — 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.