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Common exoplanet 18 EP

HD 144899 b

RA 242.5721° · Dec -47.9147° · exoplanet

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Score breakdown

· 3 badges
18 pts · Common
Common 22 pts → Uncommon
  • Eccentric orbit +9
  • Confirmed exoplanet +5
  • Neptune-like +4
Total score 18

4 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Neptune-like · +4
  • Eccentric orbit · +9

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 9 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 May — 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. ≈ 6.6 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.03
diameter km
60847.074
discovery facility
Multiple Observatories
discovery method
Radial Velocity
discovery year
2022
dist ly
377.2483
eccentricity
0.821
eq temp k
770.87
host star teff
6126
insolation
58.843
mag
8.97
mass earth
20.341
name
HD 144899 b
orbital period days
40.4391
radius earth
4.77
semi major au
0.242
sys num planets
1
sys num stars
1

About HD 144899 b

HD 144899 b is a common exoplanet. It lies about 377.2 light-years from Earth, shines at apparent magnitude 8.97, has an equilibrium temperature near 771 K and spans roughly 4.77 Earth radii.

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 8.97, it is an easy target for binoculars.

Like any astronomical target, HD 144899 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 144899 b is a common exoplanet

HD 144899 b scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Neptune-like and Eccentric orbit — 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.