What is the density of Mercury and Venus?

Expert Answers

An illustration of the letter 'A' in a speech bubbles

The density of a substance is the ratio of its mass to its volume. Assuming that planets are perfectly spherical, their radius can be used to calculate their volume. 

Mercury has a radius of 2435 km and a mass of 3.3 x 10^26 gm. The same numbers can be reported as 0.38 earth radii and 0.055 earth masses, respectively. The latter numbers make use of the earth's radius and mass as an equivalent set of units for measuring properties of other planets.

Using these numbers, the density of Mercury is 5.427 gm/cm^3.

Similarly, Venus has a radius of 6052 km (or 0.95 Earth radii) and a mass of 4.87 x 10^27 gm (or 0.815 Earth Masses). Using these numbers, the density of planet Venus is 5.24 gm/cm^3.

Approved by eNotes Editorial Team

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial