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EarthCD Cet b
0.01 AU0.1110100 AU MercuryEarthJupiterNeptune CD Cet b · 0.019 AU
Diagram, not a photograph. Sizes to scale; distance from the star on a logarithmic scale, worked out from the orbital period and the star’s mass. The planet’s colour shows its equilibrium temperature (warm), not its real colour. Source: NASA Exoplanet Archive.

Confirmed exoplanet · Database record + computed analysis

CD Cet b

A confirmed world orbiting CD Cet, 28.1 light-years away.

28.1 light-years (8.6 pc) Discovered 2020 · Radial Velocity

A super-Earth

1.82 Earth radii. Worlds between Earth and Neptune in size are the most common in the galaxy, yet our Solar System has none, which is why each one matters.

The orbit

Its year, one full orbit, takes just 2.3 Earth days. Orbiting this tightly around a cool star, it is very likely tidally locked: one hemisphere in permanent day, the other in permanent night.

Temperature and starlight

Its equilibrium temperature (the airless-world estimate) is about 191 °C. Above water's boiling point. It receives 8.6 times the starlight Earth gets.

Its sun

Its star is a red dwarf (3,130 K surface), type M5.0 V: small, dim, flare-prone, and destined to outlive the Sun many times over.

How far is that, really?

At 28 light-years, tonight's light from this system left it around the year 1997. That is close by galactic standards, which makes it a prime target for follow-up telescopes. A Voyager-speed probe would need roughly 496,680 years to get there.

How we found it

It was found by the radial-velocity method: the planet's gravity swings its star in a small circle, and that wobble shows up as a rhythmic Doppler shift in the starlight. The wobble's size gives the planet's minimum mass. The discovery was announced in 2020 from Calar Alto Observatory.

Everything above is computed from the archive’s measured values for this planet. Where a quantity is missing, the statement is omitted rather than guessed.

About this record

The measured values come from the NASA Exoplanet Archive, and any missing value has not been determined yet; the Atlas never fills gaps with guesses. More standout worlds: Proxima b, TRAPPIST-1e, K2-18 b, 55 Cancri e, and the detection methods that found them all.