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Uncommon exoplanet 30 EP

HD 40307 f

RA 88.5172° · Dec -60.0237° · exoplanet

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Score breakdown

· 4 badges
30 pts · Uncommon
Uncommon 33 pts → Rare
  • Richly packed system +14
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 30

3 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Multi-planet system · +6
  • Richly packed system · +14

Trivia

What makes it special

  • 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. ≈ 741.4 thousand years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 65.9 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 422 years in a starship at a tenth of light speed.
  • Distance. 42.2 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1984.

Saying hello

  • Say hello. A radio message and its reply would take 84.4 years round-trip.

Standing on it

  • A year here. A full year lasts just 51.8 Earth days.

By the numbers

  • Size. About 2.1× the width of Earth.
  • Volume. About 9.7 Earths could fit inside it.
  • Mass. About 5.2× the mass of Earth.
  • Your weight. You'd weigh about 1.1× your Earth weight standing here.
  • Temperature. A scorching 125°C on average.

How we found it

  • Discovery. Found by La Silla Observatory using the radial velocity method.

Cosmic context

  • Crowded system. One of at least 5 planets orbiting its star.

Properties

density gcc
2.96
discovery facility
La Silla Observatory
discovery method
Radial Velocity
dist ly
42.1925
eccentricity
0.02
eq temp k
398
insolation
3.7636
mass earth
5.2
name
HD 40307 f
orbital period days
51.76
radius earth
2.13
sys num planets
5

About HD 40307 f

HD 40307 f is an uncommon exoplanet. It lies about 42.2 light-years from Earth, has an equilibrium temperature near 398 K, spans roughly 2.13 Earth radii and weighs about 5.2 Earth masses.

Crammed into a system of five or more planets.

How to see it

Like any astronomical target, HD 40307 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 HD 40307 f is an uncommon exoplanet

HD 40307 f scores 30 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Sub-Neptune, 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.