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EarthNeptuneJupiterROXs 42 B b
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 (scorching), not its real colour. Source: NASA Exoplanet Archive.

Confirmed exoplanet · Database record + computed analysis

ROXs 42 B b

A confirmed world orbiting ROXs 42 B, 468.3 light-years away.

468.3 light-years (143.6 pc) Discovered 2013 · Imaging

A gas giant

12.50 Earth radii, Jupiter-class (Jupiter is 11.2). With 2860.0 Earth masses packed into that size, its density points to rock and iron rather than gas.

Temperature and starlight

Its equilibrium temperature (the airless-world estimate) is about 1,702 °C. Hot enough to melt copper; any surface would glow.

Its sun

Its star is a red dwarf (3,433 K surface), type M0: small, dim, flare-prone, and destined to outlive the Sun many times over. The system holds 2 stars, so its skies have more than one sun.

How far is that, really?

At 468 light-years, tonight's light from this system left it around the year 1557. A Voyager-speed probe would need roughly 8,285,935 years to get there.

How we found it

It was directly imaged, one of the rare planets actually photographed as its own point of light, possible only for young, hot, wide-orbiting giants. The discovery was announced in 2013 from Multiple Observatories.

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.