About HR 858 d
HR 858 d is a common exoplanet. It lies about 104.3 light-years from Earth, has an equilibrium temperature near 1,061 K, spans roughly 2 Earth radii and weighs about 7.1 Earth masses.
One of at least 3 planets orbiting its star.
Common exoplanet 20 EP
HR 858 d
RA 42.9850° · Dec -30.8141° · exoplanet
Score breakdown
· 4 badgesCommon 24 pts → Uncommon
- Multi-planet system +6
- Confirmed exoplanet +5
- Sub-Neptune +5
- Found by TESS +4
Total score 20
4 more points to reach Uncommon.
Badges
- Confirmed exoplanet · +5
- Sub-Neptune · +5
- Multi-planet system · +6
- Found by TESS · +4
Trivia
Could we get there?
- Verdict. Hopelessly far for any craft humanity can build today.
Getting there
- Aboard Voyager 1. ≈ 1.8 million years at Voyager 1's speed (17 km/s).
- Fastest probe ever. ≈ 162.8 thousand years even at the Parker Solar Probe's 192 km/s.
- At 10% light speed. ≈ 1043 years in a starship at a tenth of light speed.
- Distance. 104 light-years from Earth.
Look-back time
- Look-back time. The light you'd see left around the year 1922.
Saying hello
- Say hello. A radio message and its reply would take 209 years round-trip.
Standing on it
- A year here. A full year lasts just 11.2 Earth days.
By the numbers
- Size. About 2× the width of Earth.
- Volume. About 8 Earths could fit inside it.
- Mass. About 7.1× the mass of Earth.
- Your weight. You'd weigh about 1.8× your Earth weight standing here.
- Temperature. Around 788°C — hotter than a self-cleaning oven.
How we found it
- Discovery. Found by Transiting Exoplanet Survey Satellite (TESS) using the transit method.
Cosmic context
- Crowded system. One of at least 3 planets orbiting its star.
Properties
- density gcc
- 4.9
- discovery facility
- Transiting Exoplanet Survey Satellite (TESS)
- discovery method
- Transit
- dist ly
- 104.2525
- eccentricity
- 0
- eq temp k
- 1061
- insolation
- 217
- mass earth
- 7.1
- name
- HR 858 d
- orbital period days
- 11.2305
- radius earth
- 2.001
- sys num planets
- 3
How to see it
Like any astronomical target, HR 858 d 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 HR 858 d is a common exoplanet
HR 858 d scores 20 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.
That score comes from 4 science badges — Confirmed exoplanet, Sub-Neptune, Multi-planet system and Found by TESS — 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.