◆ Mercury

  Mercury is the 1st planet in the solar system, a rocky world.

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  Type              Planet
  Magnitude         -1.3
  Distance          1.25 AU, 10 light-minutes
  Apparent size     5″
  Illuminated       91%

  Known as
  Symbol            ☿

  Physical
  Radius            2,439 km, 0.38 of Earth's
  Mass              0.055 of Earth's
  Density           5.43 g/cm3
  Surface gravity   3.7 m/s2, 0.38x Earth's
  Escape velocity   4.4 km/s
  Day               58.6 Earth days
  Year              88 Earth days
  Albedo            0.11, reflects 11% of the light hitting it
  Temperature       440 K, 167 C
  Moons             none

  More information about Mercury

  Mercury never appears more than 28 degrees away from the Sun in our sky,
  so it is only ever visible low down in twilight, for a few weeks at a
  time, before it is lost in the glare again. Copernicus is said to have
  died without ever having seen it. It has almost no atmosphere, and its
  spin and its orbit are so nearly matched that the time from one sunrise
  to the next lasts two of its years. Its name comes from merx, "goods for
  sale": the god of trade, matched to Babylonian Nabu, the scribe. The
  metal is named after the planet rather than the other way round, which
  is why Swahili calls it Zebaki, from the Arabic الزئبق, "quicksilver".

  History
  Discovered      known since antiquity
  First visited   Mariner 10, 1974
  Missions        Mariner 10    1974-1975
                  MESSENGER     2008-2015
                  BepiColombo   2021-

  Etymology
  From            Latin
  Reading         Mercurius
  Literally       of merchandise

  where it is tonight:  skymap.sh/Mercury