Kepler-1520 b
Kepler-1520 b — a DISINTEGRATING planet: a small rocky world (no larger than Mercury) so fiercely heated (~1,400 K) that its surface is vaporising and streaming away as a comet-like tail of dust. Its transits vary wildly in depth because what crosses the star is a shifting DUST CLOUD, not a solid disc — so the apparent ~5.8-Earth-radius 'size' is the dust, not the body, and no real radius or mass is quoted. It may fully crumble in ~100 million years. Never imaged — the tail shown is the inferred dust plume, not the unseen body.
Key facts
Science
Physical
- Radius
- Not measured
- No real size or mass is known: the transit is of a shifting DUST CLOUD boiling off the planet, not a solid disc, so the ~5.8-Earth-radius 'size' is the dust, not the body (the real planet is thought to be no larger than Mercury). No density is quoted.
Orbital
- Semi-major axis
- 1,929,813 km
- From the NASA Exoplanet Archive (transit; the transit traces the dust cloud)
- Eccentricity
- 0
- From the NASA Exoplanet Archive (transit; the transit traces the dust cloud)
- Inclination
- 0.00 °
- From the NASA Exoplanet Archive (transit; the transit traces the dust cloud)
- Orbital period
- 15.69 hours
- From the NASA Exoplanet Archive (transit; the transit traces the dust cloud)
- Perihelion
- 1,929,813 km
- Computed from the orbital elements
- Aphelion
- 1,929,813 km
- Computed from the orbital elements
- Mean orbital velocity
- 215 km/s
- Computed from the orbital elements
Composition
- Bulk composition
- A small rocky world (thought to be no larger than Mercury) so fiercely heated (~1,400 K) that its surface is vaporising and streaming away as a comet-like tail of dust. Its transits vary wildly in depth because what crosses the star is a changing cloud of dust, not a solid disc — the first clear case of a planet caught actively disintegrating. It may fully crumble in perhaps ~100 million years. The comet-like dust tail shown here is the phenomenon inferred from that variable transit depth (Rappaport et al. 2012), not the unseen body — the planet itself has never been imaged.
- Surface appearance
- Appearance based on NASA/JPL-Caltech's artist's concept. No spacecraft has imaged this world, so its real appearance is unknown — The surface shown is an artistic representation, shown only in Visual mode; Realism shows a plain spectral colour.
Radiation & temperature
- Insolation
- 1,306 S⊕ · 1,306× the sunlight Earth receives
- Computed from Kepler-1520's luminosity and the orbital distance (inverse-square; Earth's sunlight = 1).
- Equilibrium temperature
- 1,437 K (1,164 °C)
- Computed model value for its 16-hour orbit — hot enough to vaporise rock; not measured.
Discovery & history
- Method
- Transit detection
- Name
- A Kepler-mission designation (KIC 12557548 b); no IAU proper name.
Its erratic, ever-changing transit depths (found in Kepler data, 2012) betrayed a trailing cloud of vaporised rock — the first clear case of a planet caught actively disintegrating.
Images
Images from open archives · credit shown per image