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Anomaly exoplanet 71 EP

HIP 41378 f

RA 126.6158° · Dec 10.0804° · exoplanet

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Score breakdown

· 6 badges
71 pts · Anomaly
Anomaly 95 pts → Mythic
  • In the habitable zone +30
  • Richly packed system +14
  • Puffy low-density world +12
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 71

24 more points to reach Mythic.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Gas giant · +4
  • Puffy low-density world · +12
  • Multi-planet system · +6
  • Richly packed system · +14

Trivia

What makes it special

  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist.
  • Cotton-candy planet. So low-density it would float on water.
  • Packed system. Crammed into a system of five or more planets.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 6.1 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 541.3 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 3467 years in a starship at a tenth of light speed.
  • Distance. 347 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1679.

Saying hello

  • Say hello. A radio message and its reply would take 693 years round-trip.

Standing on it

  • A year here. A full year lasts just 542 Earth days.

By the numbers

  • Size. About 9.2× the width of Earth.
  • Volume. About 779 Earths could fit inside it.
  • Mass. About 12× the mass of Earth.
  • Your weight. You'd weigh about 0.1× 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 21°C average.

How we found it

  • Discovery. Found by K2 using the transit method.

Cosmic context

  • Crowded system. One of at least 6 planets orbiting its star.

Properties

density gcc
0.09
discovery facility
K2
discovery method
Transit
dist ly
346.668
eq temp k
294
habitable zone
yes
insolation
1.24
mass earth
12
name
HIP 41378 f
orbital period days
542.0797
radius earth
9.2
sys num planets
6

About HIP 41378 f

HIP 41378 f is an anomaly exoplanet. It lies about 346.7 light-years from Earth, has an equilibrium temperature near 294 K, spans roughly 9.2 Earth radii and weighs about 12 Earth masses.

Sits where it's neither too hot nor too cold — liquid water could exist.

How to see it

Like any astronomical target, HIP 41378 f 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 HIP 41378 f is an anomaly exoplanet

HIP 41378 f scores 71 points on Spacedle's rarity scale, which places it in the anomaly tier. Another 24 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, In the habitable zone, Gas giant, Puffy low-density world, Multi-planet system and Richly packed system — 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.