Convert Megaparsec (Mpc) to Gigameter (Gm) instantly.
About these units
Megaparsec (Mpc)
A megaparsec is equal to one million parsecs, making it one of the principal units for describing intergalactic distances and the scale of the observable universe. Astronomers use Mpc to measure the distances between galaxies, galaxy groups, and galaxy clusters, as well as to express the scale of cosmic structures like the cosmic web. Megaparsecs are also central to cosmology because the Hubble constant — which describes the rate of cosmic expansion — is measured in units of kilometers per second per megaparsec. Thus, the Mpc sits at the heart of research on dark energy, large-scale structure formation, and the Big Bang. While hardly intuitive for everyday understanding, the megaparsec offers unmatched practicality for professional astronomy. It simplifies equations and visualization of the universe at the grandest scales.
Gigameter (Gm)
A gigameter, one billion meters (10⁹ m), moves firmly into interplanetary territory. Astronomers use gigameters to express distances within the solar system, such as the average separation between planets or the orbital paths of spacecraft. For example, the Earth–Moon distance (~384,000 km) can be expressed as 0.384 Gm, and distances to nearby planets often fall in the range of tens or hundreds of gigameters depending on orbital positions. The gigameter is particularly useful in scientific models where distances are massive but still fall short of interstellar scales. It reduces the need for unwieldy scientific notation and gives researchers a manageable unit for calculations involving gravitational fields, orbital dynamics, and space mission planning.