About BD+20 2457 b
BD+20 2457 b is an epic exoplanet. It lies about 5,021.9 light-years from Earth, has an equilibrium temperature near 1,160 K, spans roughly 12.1 Earth radii and weighs about 6,807.63 Earth masses.
Packed denser than solid iron.
Epic exoplanet 53 EP
BD+20 2457 b
RA 154.1868° · Dec 19.8913° · exoplanet
Score breakdown
· 6 badgesEpic 68 pts → Anomaly
- Denser than iron +18
- Hot Jupiter +10
- Distant (>1000 ly) +10
- Multi-planet system +6
- Confirmed exoplanet +5
- Gas giant +4
Total score 53
15 more points to reach Anomaly.
Badges
- Confirmed exoplanet · +5
- Gas giant · +4
- Hot Jupiter · +10
- Denser than iron · +18
- Multi-planet system · +6
- Distant (>1000 ly) · +10
Trivia
What makes it special
- Heavyweight. Packed denser than solid iron.
Could we get there?
- Verdict. Impossible with our current technology — and the next millennium of it.
Getting there
- Aboard Voyager 1. ≈ 88.2 million years at Voyager 1's speed (17 km/s).
- Fastest probe ever. ≈ 7.8 million years even at the Parker Solar Probe's 192 km/s.
- At 10% light speed. ≈ 50.2 thousand years in a starship at a tenth of light speed.
- Distance. 5022 light-years from Earth.
Look-back time
- Look-back time. Its light left before the last ice age ended.
Saying hello
- Say hello. A radio message and its reply would take 10 thousand years round-trip.
Standing on it
- A year here. A full year lasts just 380 Earth days.
By the numbers
- Size. About 12.1× the width of Earth.
- Volume. About 1772 Earths could fit inside it.
- Mass. Roughly 6808× Earth's mass — about 21.4 Jupiters.
- Your weight. You'd weigh about 46.5× your Earth weight standing here.
- Density. Denser than solid iron.
- Temperature. Around 887°C — hotter than a self-cleaning oven.
How we found it
- Discovery. Found by McDonald Observatory using the radial velocity method.
Cosmic context
- Crowded system. One of at least 2 planets orbiting its star.
Properties
- density gcc
- 21.1
- discovery facility
- McDonald Observatory
- discovery method
- Radial Velocity
- dist ly
- 5021.8565
- eccentricity
- 0.15
- eq temp k
- 1159.67
- insolation
- 703.4998
- mass earth
- 6807.63
- name
- BD+20 2457 b
- orbital period days
- 379.63
- radius earth
- 12.1
- sys num planets
- 2
How to see it
Like any astronomical target, BD+20 2457 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+20 2457 b is an epic exoplanet
BD+20 2457 b scores 53 points on Spacedle's rarity scale, which places it in the epic tier. Another 15 points would lift it into a rarer tier.
That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Denser than iron, Multi-planet system and Distant (>1000 ly) — 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.