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Uncommon exoplanet 23 EP

MXB 1658-298 b

RA 255.5273° · Dec -29.9456° · exoplanet

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Score breakdown

· 3 badges
23 pts · Uncommon
Uncommon 34 pts → Rare
  • Circumbinary (orbits both stars) +14
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 23

11 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Circumbinary (orbits both stars) · +14

Trivia

Hard to believe

  • Denser than iron. It is packed tighter than solid iron — whatever it is made of, it is not ordinary rock.

What it actually is

  • What it is made of. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.

Find it in the sky

  • 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 June — that's when to go looking.

Standing on it

  • Two suns. Two suns would rise and set in its sky — a real-life Tatooine.
  • A year here. A full year lasts about 2.1 Earth years.

By the numbers

  • Size. About 12× the width of Earth.
  • Your weight. You'd weigh about 52.3× your Earth weight standing here.

Properties

circumbinary
yes
density gcc
24
diameter km
153074.4
discovery facility
Multiple Observatories
discovery method
Eclipse Timing Variations
discovery year
2017
mass earth
7532.571
name
MXB 1658-298 b
orbital period days
760
radius earth
12
semi major au
1.613
sys num planets
1
sys num stars
2

Nearby objects

About MXB 1658-298 b

MXB 1658-298 b is an uncommon exoplanet. It spans roughly 12 Earth radii, weighs about 7,532.57 Earth masses, completes an orbit every 760 days and belongs to a system of 1 known planets.

Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.

How to see it

Like any astronomical target, MXB 1658-298 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 MXB 1658-298 b is an uncommon exoplanet

MXB 1658-298 b scores 23 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 11 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Gas giant and Circumbinary (orbits both stars) — 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.