Mass of Venus
| Value | 4.8675e24 kg |
| Status | Measured: ± 1.10e+20 kg (0.000023 relative) |
| Source | NASA planetary fact sheet; GM from JPL DE440 divided by CODATA 2022 G |
| Categories | Astronomicalsolar-systemplanets |
| microgram | 4.8675000e+33 μg |
| milligram | 4.8675000e+30 mg |
| gram | 4.8675000e+27 g |
| kilogram | 4.8675000e+24 kg |
| metric tonne | 4.8675000e+21 t |
| ounce | 1.7169601e+26 oz |
| pound | 1.0731001e+25 lb |
| stone | 7.6650004e+23 st |
| US short ton | 5.3655003e+21 ton |
| grain | 7.5117004e+28 gr |
| unified atomic mass unit (dalton) | 2.9312770e+51 u |
Learning zone
Venus is Earth's near-duplicate in mass and radius, which is exactly what makes it the most important comparison planet we have: same starting materials, same rough size, radically different outcome. A runaway greenhouse drove the surface to 737 K under 92 bar of carbon dioxide, hot enough to melt lead, and Soviet Venera landers survived only tens of minutes on the surface in the 1970s and 80s.
The mass came into focus with Mariner 2's 1962 flyby, the first successful interplanetary mission, and was refined by Magellan's radar mapping. Venus also has no detectable magnetic field and rotates retrograde once every 243 days — longer than its 225-day year — which is one reason its transits, in 1761 and 1769, could be timed from so many places on Earth at once in the campaigns that first measured the astronomical unit.