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Rare exoplanet 37 EP

TOI-1855 b

RA 205.3540° · Dec 17.6869° · exoplanet

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Score breakdown

· 5 badges
37 pts · Rare
Rare 46 pts → Epic
  • Lava world +14
  • Hot Jupiter +10
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by TESS +4
Total score 37

9 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Lava world · +14
  • Found by TESS · +4

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. ≈ 10.1 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 900.5 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 5768 years in a starship at a tenth of light speed.
  • Distance. 577 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1449.

Saying hello

  • Say hello. A radio message and its reply would take 1154 years round-trip.

Standing on it

  • A year here. A full year lasts just 1.4 Earth days.

By the numbers

  • Size. About 18.5× the width of Earth.
  • Volume. About 6326 Earths could fit inside it.
  • Mass. Roughly 360× Earth's mass — about 1.1 Jupiters.
  • Your weight. You'd weigh about 1.1× your Earth weight standing here.
  • Density. Less dense than water — drop it in a big enough ocean and it would float.
  • Temperature. Around 1428°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by Transiting Exoplanet Survey Satellite (TESS) using the transit method.

Properties

density gcc
0.31
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
dist ly
576.7514
eccentricity
0.033
eq temp k
1701
insolation
852.162
mass earth
360.0996
name
TOI-1855 b
orbital period days
1.3641
radius earth
18.4948
sys num planets
1

About TOI-1855 b

TOI-1855 b is a rare exoplanet. It lies about 576.8 light-years from Earth, has an equilibrium temperature near 1,701 K, spans roughly 18.49 Earth radii and weighs about 360.1 Earth masses.

Its surface is likely an ocean of molten rock.

How to see it

Like any astronomical target, TOI-1855 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 TOI-1855 b is a rare exoplanet

TOI-1855 b scores 37 points on Spacedle's rarity scale, which places it in the rare tier. Another 9 points would lift it into a rarer tier.

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

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.