WASP-17

Star

WASP-17 — a hot, bright F-type star ~1,320 light-years away in Scorpius. It hosts one of the largest, lowest-density planets known, on a backward orbit.

Open in 3D viewSee WASP-17 in the live, interactive 3D map

Key facts

Mass

4.53 × 10³⁰ kg

2.28 M☉

Radius

1,036,593 km

1.49× wider than the Sun

Surface temperature

6,550 K (6,277 °C)

Spectral type

F4 (a hot white star, ~2.3 solar masses)

Science

Physical

Mass: 4.53 × 10³⁰ kg · 2.28 M☉
Radius: 1,036,593 km · 1.49× wider than the Sun
Density: 972 kg/m³ · 0.97× water; Computed from mass and radius
Spectral type: F4 (a hot white star, ~2.3 solar masses)

Motion through space

Proper motion: 0.0125 arcseconds per year · its drift across our sky; SIMBAD — 2020yCat.1350....0G, 2018A&A...616A...7S
Radial velocity: -49.6 km/s · approaching the Sun; SIMBAD — 2020yCat.1350....0G, 2018A&A...616A...7S
Speed across our line of sight: 24 km/s; Computed from proper motion and parallax
Speed through space, relative to the Sun: 55.1 km/s; Computed from proper motion, parallax and radial velocity

Composition

By mass: A hot, bright F-type star in Scorpius; its giant planet orbits backward (retrograde).

Temperature

Surface: 6,550 K (6,277 °C)

Radiation & temperature

Luminosity: 1.41 × 10²⁷ W · 3.68 L☉
Surface temperature: 6,550 K (6,277 °C)
Peak wavelength: 442 nm · violet-blue light; Computed (Wien's law) from the surface temperature

Discovery & history

Method: Telescope
Name: A WASP-survey catalogue designation.

Catalogued by the WASP survey; its 2009 planet was among the first shown to orbit retrograde.

Images

Where to find it — in Scorpius, the Scorpion (IAU constellation chart). To the eye it is a single point of light; no telescope has imaged its surface. — IAU / Sky & Telescope, R. Sinnott & R. Fienberg (CC BY 3.0) · Wikimedia Commons

Images from open archives · credit shown per image