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Uncommon exoplanet 27 EP

HD 77338 b

RA 135.3022° · Dec -25.5282° · exoplanet

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Score breakdown

· 4 badges
27 pts · Uncommon
Uncommon 34 pts → Rare
  • Tidally locked +10
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Neptune-like +4
Total score 27

7 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Neptune-like · +4
  • Tidally locked · +10
  • Orbits a Sun-like star · +8

Trivia

What it actually is

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • What it is made of. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 8.6 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around February — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 2.6 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.25
diameter km
52555.544
discovery facility
La Silla Observatory
discovery method
Radial Velocity
discovery year
2012
dist ly
149.8198
eccentricity
0.09
eq temp k
1035.54
host star teff
5341
insolation
152.7909
mag
8.63
mass earth
15.9
name
HD 77338 b
orbital period days
5.7361
radius earth
4.12
semi major au
0.06
spect
K0 IV
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About HD 77338 b

HD 77338 b is an uncommon exoplanet. It lies about 149.8 light-years from Earth, shines at apparent magnitude 8.63, has spectral type K0 IV and has an equilibrium temperature near 1,036 K.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 8.63, it is an easy target for binoculars.

Like any astronomical target, HD 77338 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 HD 77338 b is an uncommon exoplanet

HD 77338 b scores 27 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 7 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Neptune-like, Tidally locked and Orbits a Sun-like star — 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.