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  2. Geological history of Mars - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_Mars

    Numerous attempts [3] [4] [5] have been made over the years to determine an absolute Martian chronology (timeline) by comparing estimated impact cratering rates for Mars to those on the Moon. If the rate of impact crater formation on Mars by crater size per unit area over geologic time (the production rate or flux) is known with precision, then ...

  3. Timekeeping on Mars - Wikipedia

    en.wikipedia.org/wiki/Timekeeping_on_Mars

    It is slightly shorter than the sidereal year due to the precession of Mars' rotational axis. The precession cycle is 93,000 Martian years (175,000 Earth years), much longer than on Earth. Its length in tropical years can be computed by dividing the difference between the sidereal year and tropical year by the length of the tropical year.

  4. Pre-Noachian - Wikipedia

    en.wikipedia.org/wiki/Pre-Noachian

    The lower boundary of the Pre-Noachian period on Mars is characterized by the emergence of significant geological activity and the initial shaping of the planet's surface during its early history. This boundary is defined by the presence of ancient cratered terrains, volcanic constructs, and impact ejecta deposits dating back to the earliest ...

  5. Amazonian (Mars) - Wikipedia

    en.wikipedia.org/wiki/Amazonian_(Mars)

    The Amazonian period has been dominated by impact crater formation and Aeolian processes with ongoing isolated volcanism occurring in the Tharsis region and Cerberus Fossae, including signs of activity as recently as a tens of thousands of years ago in the latter [4] and within the past few million years on Olympus Mons, implying they may still ...

  6. Mars - Wikipedia

    en.wikipedia.org/wiki/Mars

    Download as PDF; Printable version; ... Sidereal rotation period. 1.025 957 d ... 1.35 million Earth years ago, Mars had an eccentricity of roughly 0.002, ...

  7. Geology of Mars - Wikipedia

    en.wikipedia.org/wiki/Geology_of_Mars

    Generalised geological map of Mars [1] Mars as seen by the Hubble Space Telescope. The geology of Mars is the scientific study of the surface, crust, and interior of the planet Mars. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is analogous to the field of terrestrial geology.

  8. Rotation period (astronomy) - Wikipedia

    en.wikipedia.org/wiki/Rotation_period_(astronomy)

    In astronomy, the rotation period or spin period [1] of a celestial object (e.g., star, planet, moon, asteroid) has two definitions. The first one corresponds to the sidereal rotation period (or sidereal day), i.e., the time that the object takes to complete a full rotation around its axis relative to the background stars (inertial space).

  9. Milankovitch cycles - Wikipedia

    en.wikipedia.org/wiki/Milankovitch_cycles

    The orbital period (the length of a sidereal year) ... From 1–3 million years ago, climate cycles matched the 41,000-year cycle in obliquity. ... Download as PDF ...