About ZTF J1828+2308 b
ZTF J1828+2308 b is a rare exoplanet. It lies about 658.3 light-years from Earth, spans roughly 11.13 Earth radii, weighs about 6,356.57 Earth masses and completes an orbit every 0.11 days.
Packed denser than solid iron.
Rare exoplanet 41 EP
ZTF J1828+2308 b
RA 277.2032° · Dec 23.1439° · exoplanet
Score breakdown
· 4 badgesRare 46 pts → Epic
- Denser than iron +18
- Ultra-short period +14
- Confirmed exoplanet +5
- Gas giant +4
Total score 41
5 more points to reach Epic.
Badges
- Confirmed exoplanet · +5
- Gas giant · +4
- Ultra-short period · +14
- Denser than iron · +18
Trivia
What makes it special
- Heavyweight. Packed denser than solid iron.
Could we get there?
- Verdict. Hopelessly far for any craft humanity can build today.
Getting there
- Aboard Voyager 1. ≈ 11.6 million years at Voyager 1's speed (17 km/s).
- Fastest probe ever. ≈ 1 million years even at the Parker Solar Probe's 192 km/s.
- At 10% light speed. ≈ 6583 years in a starship at a tenth of light speed.
- Distance. 658 light-years from Earth.
Look-back time
- Look-back time. The light you'd see left around the year 1368.
Saying hello
- Say hello. A radio message and its reply would take 1317 years round-trip.
Standing on it
- A year here. A full year lasts just 0.1 Earth days.
By the numbers
- Size. About 11.1× the width of Earth.
- Volume. About 1379 Earths could fit inside it.
- Mass. Roughly 6357× Earth's mass — about 20 Jupiters.
- Your weight. You'd weigh about 51.3× your Earth weight standing here.
- Density. Denser than solid iron.
How we found it
- Discovery. Found by Zwicky Transient Facility using the transit method.
Properties
- density gcc
- 25.3
- discovery facility
- Zwicky Transient Facility
- discovery method
- Transit
- dist ly
- 658.2709
- mass earth
- 6356.5681
- name
- ZTF J1828+2308 b
- orbital period days
- 0.112
- radius earth
- 11.1305
- sys num planets
- 1
How to see it
Like any astronomical target, ZTF J1828+2308 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 ZTF J1828+2308 b is a rare exoplanet
ZTF J1828+2308 b scores 41 points on Spacedle's rarity scale, which places it in the rare tier. Another 5 points would lift it into a rarer tier.
That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Ultra-short period and Denser than iron — 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.