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Common exoplanet 15 EP

BD+48 738 b

RA 40.7103° · Dec 49.5869° · exoplanet

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Score breakdown

· 3 badges
15 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 15

7 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4

Trivia

Hard to believe

  • It would float. It is less dense than water. Drop it in a big enough ocean and the whole world would bob on the surface.

What it actually is

  • 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 9.1 you'll want a small backyard telescope.
  • 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 October — 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. ≈ 49.9 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
0.592
diameter km
177311.18
discovery facility
McDonald Observatory
discovery method
Radial Velocity
discovery year
2011
dist ly
2842.4267
eccentricity
0.2
eq temp k
705.93
host star teff
4414
insolation
48.9779
mag
9.139
mass earth
289.2253
name
BD+48 738 b
orbital period days
392.6
radius earth
13.9
semi major au
1
spect
K0 III
sys num planets
1
sys num stars
1

Nearby objects

About BD+48 738 b

BD+48 738 b is a common exoplanet. It lies about 2,842.4 light-years from Earth, shines at apparent magnitude 9.14, has spectral type K0 III and has an equilibrium temperature near 706 K.

Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

How to see it

At apparent magnitude 9.14, a small backyard telescope will bring it into view.

Like any astronomical target, BD+48 738 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 BD+48 738 b is a common exoplanet

BD+48 738 b scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 7 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Distant (over 1,000 light-years) and Gas giant — 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.