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Common exoplanet 19 EP

HD 109749 b

RA 189.3173° · Dec -40.8121° · exoplanet

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Score breakdown

· 3 badges
19 pts · Common
Common 24 pts → Uncommon
  • Hot Jupiter +10
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 19

5 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10

Trivia

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 3.6 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 321.3 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 2057 years in a starship at a tenth of light speed.
  • Distance. 206 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1820.

Saying hello

  • Say hello. A radio message and its reply would take 411 years round-trip.

Standing on it

  • A year here. A full year lasts just 5.2 Earth days.

By the numbers

  • Size. About 11.1× the width of Earth.
  • Volume. About 1368 Earths could fit inside it.
  • Mass. Roughly 85.8× Earth's mass — about 0.3 Jupiters.
  • Your weight. You'd weigh about 0.7× your Earth weight standing here.
  • Density. Less dense than water — drop it in a big enough ocean and it would float.
  • Temperature. Around 978°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by W. M. Keck Observatory using the radial velocity method.

Properties

density gcc
0.345
discovery facility
W. M. Keck Observatory
discovery method
Radial Velocity
dist ly
205.7461
eccentricity
0
eq temp k
1250.83
insolation
409.4961
mass earth
85.8141
name
HD 109749 b
orbital period days
5.2399
radius earth
11.1
sys num planets
1

About HD 109749 b

HD 109749 b is a common exoplanet. It lies about 205.7 light-years from Earth, has an equilibrium temperature near 1,251 K, spans roughly 11.1 Earth radii and weighs about 85.81 Earth masses.

About 11.1× the width of Earth.

How to see it

Like any astronomical target, HD 109749 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 109749 b is a common exoplanet

HD 109749 b scores 19 points on Spacedle's rarity scale, which places it in the common tier. Another 5 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Gas giant and Hot Jupiter — 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.

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.