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Rare exoplanet 47 EP

KOI-1257 b

RA 291.2251° · Dec 44.9273° · exoplanet

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Score breakdown

· 7 badges
47 pts · Rare
Rare 50 pts → Epic
  • Two suns in its sky +12
  • Eccentric orbit +9
  • Orbits a Sun-like star +8
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by Kepler +3
Total score 47

3 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Eccentric orbit · +9
  • Found by Kepler · +3
  • Orbits a Sun-like star · +8
  • Two suns in its sky · +12

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. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.

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 14.8 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around July — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 37.6 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
2.1
diameter km
134450.348
discovery facility
Kepler
discovery method
Transit
discovery year
2014
dist ly
2139.5834
eccentricity
0.772
eq temp k
511
host star teff
5520
inclination
89.66
insolation
7.28
mag
14.818
mass earth
460.83
multi star system
yes
name
KOI-1257 b
orbital period days
86.6477
radius earth
10.54
semi major au
0.382
spect
G5 V
sys num planets
1
sys num stars
2

About KOI-1257 b

KOI-1257 b is a rare exoplanet. It lies about 2,139.6 light-years from Earth, shines at apparent magnitude 14.82, has spectral type G5 V and has an equilibrium temperature near 511 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 14.82, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, KOI-1257 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 KOI-1257 b is a rare exoplanet

KOI-1257 b scores 47 points on Spacedle's rarity scale, which places it in the rare tier. Another 3 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Gas giant, Eccentric orbit, Found by Kepler, Orbits a Sun-like star and Two suns in its sky — 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.