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EarthNeptuneJupiterHAT-P-15 b
0.01 AU0.1110100 AU MercuryEarthJupiterNeptune HAT-P-15 b · 0.096 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 (hot), not its real colour. Source: NASA Exoplanet Archive.

Confirmed exoplanet · Database record + computed analysis

HAT-P-15 b

A confirmed world orbiting HAT-P-15, 627.9 light-years away.

627.9 light-years (192.5 pc) Discovered 2010 · Transit

A gas giant

11.88 Earth radii, Jupiter-class (Jupiter is 11.2).

The orbit

Its year, one full orbit, takes just 10.9 Earth days.

Temperature and starlight

Its equilibrium temperature (the airless-world estimate) is about 631 °C. Hotter than Venus's surface. It receives 79.8 times the starlight Earth gets.

Its sun

Its star is Sun-like (5,568 K, G5; the Sun is 5,772 K).

How far is that, really?

At 628 light-years, tonight's light from this system left it around the year 1398. A Voyager-speed probe would need roughly 11,109,235 years to get there.

How we found it

It was found by the transit method: the planet crosses its star's face on schedule, dimming it by a tiny, repeating fraction. The dip's depth gives the planet's size. The discovery was announced in 2010 from HATNet.

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.