Surface Gravity of Uranus

gUranus=8.69 m/s2g_{\mathrm{Uranus}} = 8.69\ \text{m/s}^{2}
Value8.69 m/s²
StatusMeasured: ± 0.01 m/s² (0.0012 relative)
SourceNASA NSSDC Planetary Fact Sheet, Uranus (surface acceleration, eq., 1 bar; gravity without rotation 8.87 m/s²)
CategoriesAstronomicalsolar-systemplanets
Surface Gravity of Uranus in every acceleration unit
microgal869,000,000 μGal
milligal869,000 mGal
millimeter per second squared8,690 mm/s²
centimeter per second squared869 cm/s²
gal869 Gal
inch per second squared342.12598 in/s²
kilometer per hour per second31.284 km/h/s
foot per second squared28.510499 ft/s²
mile per hour per second19.438976 mph/s
meter per second squared8.69 m/s²
standard gravity0.88613339 g

Learning zone

Convention declared up front: this is the effective acceleration at the one-bar level on the equator, rotation included — the acceleration a floating instrument package would actually measure. Pure gravity at the same point, GM/r² with no centrifugal term, is 8.87 m/s²; the 17.24-hour spin refunds 0.18 m/s² of it. The NSSDC tabulates both, as "surface acceleration" and "surface gravity" respectively, and the distinction is worth learning on Uranus precisely because the two conventions differ by two per cent here and by nothing measurable on a slow rotator like Venus.

Either way the number lands near Earth's 9.81: fourteen and a half Earth masses spread through sixty-three Earth volumes produce, at the cloud tops, gravity you would barely notice was foreign. It declines with the interior's diffuse structure too — gravity harmonics from Voyager and from precessing rings are among the few windows into how the ice and rock are layered inside.