Scribd
Upload
59 views1 page

Mercury Is The Smallest: Mariner 10 Messenger Bepicolombo

Mercury is the smallest planet in the Solar System and orbits the Sun closest of all planets, completing its orbit every 87.97 Earth days. It is named after the Roman god Mercury. Mercury orbits within Earth's orbit and can only be seen just after sunset or just before sunrise from Earth. Mercury rotates in a unique way where it rotates three times on its axis for every two revolutions around the Sun. It has the largest orbital eccentricity and tilts least of all planets.

Uploaded by

Ezzie Doro
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as DOCX, PDF, TXT or read online on Scribd
59 views1 page

Mercury Is The Smallest: Mariner 10 Messenger Bepicolombo

Mercury is the smallest planet in the Solar System and orbits the Sun closest of all planets, completing its orbit every 87.97 Earth days. It is named after the Roman god Mercury. Mercury orbits within Earth's orbit and can only be seen just after sunset or just before sunrise from Earth. Mercury rotates in a unique way where it rotates three times on its axis for every two revolutions around the Sun. It has the largest orbital eccentricity and tilts least of all planets.

Uploaded by

Ezzie Doro
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as DOCX, PDF, TXT or read online on Scribd
You are on page 1/ 1

Mercury 

is the smallest planet in the Solar System and the closest to the Sun. Its orbit around the
Sun takes 87.97 Earth days, the shortest of all the Sun's planets. It is named after the Roman
god Mercurius (Mercury), god of commerce, messenger of the gods, and mediator between gods
and mortals, corresponding to the Greek god Hermes (Ἑρμῆς). Like Venus, Mercury orbits the Sun
within Earth's orbit as an inferior planet, and its apparent distance from the Sun as viewed from
Earth never exceeds 28°. This proximity to the Sun means the planet can only be seen near the
western horizon after sunset or the eastern horizon before sunrise, usually in twilight. At this time, it
may appear as a bright star-like object but is often far more difficult to observe than Venus. From
Earth, the planet telescopically displays the complete range of phases, similar to Venus and
the Moon, which recurs over its synodic period of approximately 116 days.
Mercury rotates in a way that is unique in the Solar System. It is tidally locked with the Sun in a
3:2 spin–orbit resonance,[17] meaning that relative to the fixed stars, it rotates on its axis exactly three
times for every two revolutions it makes around the Sun.[a][18] As seen from the Sun, in a frame of
reference that rotates with the orbital motion, it appears to rotate only once every two Mercurian
years. An observer on Mercury would therefore see only one day every two Mercurian years.
Mercury's axis has the smallest tilt of any of the Solar System's planets (about 1⁄30 degree). Its orbital
eccentricity is the largest of all known planets in the Solar System;[b] at perihelion, Mercury's distance
from the Sun is only about two-thirds (or 66%) of its distance at aphelion. Mercury's surface appears
heavily cratered and is similar in appearance to the Moon's, indicating that it has been geologically
inactive for billions of years. Having almost no atmosphere to retain heat, it has surface
temperatures that vary diurnally more than on any other planet in the Solar System, ranging from
100 K (−173 °C; −280 °F) at night to 700 K (427 °C; 800 °F) during the day across the equatorial
regions.[19] The polar regions are constantly below 180 K (−93 °C; −136 °F). The planet has no
known natural satellites.
Two spacecraft have visited Mercury: Mariner 10 flew by in 1974 and 1975; and MESSENGER,
launched in 2004, orbited Mercury over 4,000 times in four years before exhausting its fuel and
crashing into the planet's surface on April 30, 2015.[20][21][22] The BepiColombo spacecraft is planned to
arrive at Mercury in 2025.

You might also like