About HAT-P-20 b
HAT-P-20 b is an uncommon exoplanet. It lies about 231.7 light-years from Earth, has an equilibrium temperature near 970 K, spans roughly 9.72 Earth radii and weighs about 2,302.9 Earth masses.
Packed denser than solid iron.
Uncommon exoplanet 27 EP
HAT-P-20 b
RA 111.9164° · Dec 24.3361° · exoplanet
Score breakdown
· 3 badgesUncommon 33 pts → Rare
- Denser than iron +18
- Confirmed exoplanet +5
- Gas giant +4
Total score 27
6 more points to reach Rare.
Badges
- Confirmed exoplanet · +5
- Gas giant · +4
- Denser than iron · +18
Trivia
What makes it special
- Heavyweight. Packed denser than solid iron.
Could we get there?
- Verdict. Hopelessly far for any craft humanity can build today.
Getting there
- Aboard Voyager 1. ≈ 4.1 million years at Voyager 1's speed (17 km/s).
- Fastest probe ever. ≈ 361.8 thousand years even at the Parker Solar Probe's 192 km/s.
- At 10% light speed. ≈ 2317 years in a starship at a tenth of light speed.
- Distance. 232 light-years from Earth.
Look-back time
- Look-back time. The light you'd see left around the year 1794.
Saying hello
- Say hello. A radio message and its reply would take 463 years round-trip.
Standing on it
- A year here. A full year lasts just 2.9 Earth days.
By the numbers
- Size. About 9.7× the width of Earth.
- Volume. About 918 Earths could fit inside it.
- Mass. Roughly 2303× Earth's mass — about 7.2 Jupiters.
- Your weight. You'd weigh about 24.4× your Earth weight standing here.
- Density. Denser than solid iron.
- Temperature. Around 697°C — hotter than a self-cleaning oven.
How we found it
- Discovery. Found by HATNet using the transit method.
Properties
- density gcc
- 13.78
- discovery facility
- HATNet
- discovery method
- Transit
- dist ly
- 231.6927
- eccentricity
- 0.015
- eq temp k
- 970
- insolation
- 85.1168
- mass earth
- 2302.899
- name
- HAT-P-20 b
- orbital period days
- 2.8753
- radius earth
- 9.718
- sys num planets
- 1
How to see it
Like any astronomical target, HAT-P-20 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-20 b is an uncommon exoplanet
HAT-P-20 b scores 27 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 6 points would lift it into a rarer tier.
That score comes from 3 science badges — Confirmed exoplanet, Gas giant and Denser than iron — 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.