Mercury's spin (rotation) and orbit are "in synch"! So part of the planet experiences double sunrises!  (1.6.x)   (1.4.1)

Mercury is a barren world that in many ways resembles Earth's Moon  (1.6.x)   (1.4.1)

Mercury is the closest planet to the Sun, so it moves in its orbit faster than any other major planet!  (1.6.x)   (1.4.1)

Right Drag with your mouse after you run the links above that display planetary orbits to get a good sense of their 3-dimensional aspects.

Are you unfamiliar with our 1.6.x and 1.4.1 links?  For an explanation  click here.

SURFACE VIEWS

Although no spacecraft has yet visited the surface of the innermost planet, much has been learned about it.  Here are links to science-based representations of Mercury's Sun-baked surface, which has often been likened to the surface of the Moon.

Barren Mercury: © SkyMarvels

Hostile Mercury: © SkyMarvels

MESSENGER Mission Site
NASA Solar System Sim

CELES-TIPS

The following will help you enjoy this page's 1.6.x and 1.4.1 links that run events directly in CELESTIA.  If you're new to the program, these tips will also help you learn to use it.

You'll find more information about many of CELESTIA's controls on our  Learning Center  page.


MERCURY

Current Views and Conditions from Earth
Current Location in the Constellations (w/ Geo-Coords)
Current Location in Orbit
Current Year's Greatest Elongations
Next Transit:  2019 Nov 11

Equatorial Radius:    2,440 km
Equatorial Radius (Earth = 1):    0.383
Rotational Flattening:    0
Mass (Earth = 1):    0.055
Volume (Earth = 1):    0.056
Mean Density (Water = 1):    5.43
Mean Density (Earth = 1):    0.984
Surface Gravity (Earth = 1):    0.378
Inclination of Axis to Orbit:    0°
Rotation Period:
      Synodic ("Day" in Earth solar* days):    175.942
      Sidereal (Earth solar* days):    58.65


Viewed from the Sun, Mercury exhibits a peculiar motion.  Its spin & elliptical orbit are synchronized,
so it appears to stop rotating every time it reaches perihelion!

Albedo (geometric):    0.14
Magnetic Field (Earth = 1):    0.017
      NASA Messenger Site Graphic  
      NASA/JPL PhotoJournal Site Graphic  

View Mercury in 3-D:  from NOAA's Science on a Sphere site, Mercury can be rotated around 2 axes.  (When link runs, click in the page's right column on "Interactive Sphere".)

Global Views (greyscale):
      North Pole    South Pole
      0° North, 0° East    0° North, 90° East
      0° North, 180° East    0° North, 270° East
Maps of Mercury's Surface (greyscale):
      Global Mosaics
      Study Mercury's Surface with QuickMap
Map of Mercury's Surface ("enhanced color"):
      Global Mosaic Map  (3.74 km per pixel)
      NASA explanation of "enhanced color" map
NASA / JPL's Photojournal pages for Mercury

NOTE:  to see Mercury's internal structure, hover your cursor over planet's image at upper-right of this page.

Number of Moons:    0
Ring System:    No

Planet Classifications:
      Inner Planet (along with Venus, Earth & Mars)
      Terrestrial Planet (primarily Earth-like structure)
      Inferior Planet (has smaller orbit than Earth)

Orbit:   (1.6.x)   (1.4.1)
      Period:    87.969 Earth solar* days
      Distance from Sun:
            Mean (Earth = 1 AU):    0.387 AU
            Mean:    57,910,000 km
            Perihelion:    46,000,000 km
            Aphelion:    69,820,000 km
      Velocity:
            Mean:    172,332 km/hr
            Min:    139,896 km/hr
            Max:    212,328 km/hr
      Eccentricity:    0.206
      Inclination to Ecliptic:    7.00°
      Spin-Orbit Resonance:    Yes, 3 to 2
            (verify Mercury's 3 rotations in each 2 orbits)

MERCURY'S SPIN-ORBIT RESONANCE
(Note: eccentricity of orbit in animation is exaggerated for emphasis.   See actual proportions of Mercury's orbit .)

      Transits (in front of the Sun):
            Frequency:    approx 13 per century
            Last 2 Transits:    2003 May 7;  2006 Nov 8
            Next 2 Transits:    2016 May 92119 Nov 11
            Reason All Currently Occur in May or November
            NASA Webpage Video of the 2006 Nov 8 Transit
            NASA Graphic of the 2006 Nov 8 Transit
            2006 Nov 8 Transit Pages:
                  NASA   ;     HMNAO

*Earth mean solar day = 24.0000 hours (24h00m00s)
  Earth sidereal day = 23.9345 hr (23h56m4.1s)

Partial Information Source: NASA Fact Sheets


ADJECTIVES MEANING
"pertaining to Mercury"

      Mercurian
      Hermian (from Greek god, Hermes)


MERCURY: Its Phases as an Inferior Planet

MERCURY'S & VENUS'S SKY PATHS 2013–2014

MERCURY
video credit: Science@NASA

MERCURY: Its Weird Solar Day over its South Pole
video credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

MESSENGER: Mercury Orbit Insertion
video credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington


DIRECT LINKS TO MORE VIDEOS

From NASA's Photojournal pages, here's  A Tribute to MESSENGER  

From NASA's Photojournal pages, here's  Mercury: Getting the Spins  

From NASA's Photojournal pages, here's  A Bit of an Exaggeration  


Back to Top

Home   Intro   News   Gallery   Sky-Gifts   Bonuses   Tips
Learning Ctr   Help   Links   Credits   Legal   Contact Us

© 2007- by Gary M. Winter.  All rights reserved.

Interested in political cartoons and humor?
Check out The HIPPLOMATS™.

SkyMarvels, Sky Marvels, SkyMarvels.com, MERCURY Info. MERCURY. All about the planet MERCURY. MERCURY'S Structure. MERCURY'S 3/2 Spin-Orbit Resonance, MERCURY'S Spin-Orbit Resonance. MERCURY'S weird double sunrises, celestia4all, celestiaforall, CELESTIA, astronomy, space, simulations, animations, downloadable astronomy posters, stars, planets, Inner Planets, Outer Planets, Inferior Planets, Superior Planets, moons, asteroids, comets, Oort Cloud, galaxy, galaxies, Milky Way, Andromeda, globular clusters, binaries, quasars, black holes, supermassive black holes, telescope, telescopes, planetarium, software, freestuff, satellites, add-ons, addons, scripts, eclipses, Solar Eclipses, Lunar Eclipses, Solar Eclipse Finder, Lunar Eclipse Finder, mutual eclipses, transits, occultations, Solar System, CELES-TOOLS, celeSTARrium, CELX, CELX programming, Freebies, Bonuses, multiple views, atronomical unit, light year, parsec, meteors, meteor showers, Perseids, Geminids, Leonids, barycenter, time, Time Zones, tides, alignments, conjunctions, oppositions, seasons, apogees, perigees, aphelion, perihelion, Earth, Luna, Mercury, Venus, Mars, Jupiter, Galilean Moons, Io, Europa, Ganymede, Callisto, Saturn, Titan, rings, Uranus, Neptune, Triton, E-MSpectrum, electromagnetic spectrum, astronaut, equinoxes, solstices, precession, rotation, spin, inclination, tilt, Ecliptic, orbits, ellipse, parabola, hyperbola

Planet Comparison HD vid.


Donate safely with: PayPal

to receive one or more
Sky-Gifts.  Your support is greatly appreciated!

SKY VIEWING
SOLAR SYSTEM
THE SUN
MERCURY
VENUS
EARTH
THE MOON
MARS
JUPITER
SATURN
URANUS
NEPTUNE
SMALLER WORLDS
STELLAR OBJECTS
EXOPLANETS
DEEP-SKY OBJECTS
SCALE OF THE COSMOS
———————
SKY-FUN / SKY-GAMES


NASA's LATEST

MERCURY MESSENGER status (completed mission with impact on Mercury as expected 2015 Apr 30)


MERCURY FUN FACTS

Relative to its overall size, Mercury has a larger metallic core than any other planet!

Mercury's day is almost one half of an "Earth year" long!

Though the 8 major planets do not possess particularly elongated orbits,  Mercury's orbit  is the most elongated or elliptical of them.

Due to Mercury's spin-orbit resonance, the Sun appears to stop and even reverse in the planet's sky!

Mercury's lack of moons is partly due to its nearness to the Sun!  The solar gravity makes it harder for Mercury to retain orbiting bodies.

MERCURY INTERACTIVES

QUICK ACCESS LIST

Note: some links are echoed elsewhere on this page and may include descriptive text.

From NOAA's Science on a Sphere site is a  3-D Mercury  that can be rotated around 2 axes.  (When link runs click in the page's right column on "Interactive Sphere".)

Links to interactive features that show Mercury's orbit in 3-D can be found on our  Solar System page

From ScienceNetLinks, here's  Make a Mission to Mercury

Study Mercury's Surface with QuickMap

From the MESSENGER site, below are links to nice Flash animations highlighting how Mercury's orbit and rotation create the planet's long and peculiar day.  And more!

Day on Mercury  shows how the Sun appears to halt in Mercury's sky!

Comparing the Sun's Size in Earth's and Mercury's Skies  shows how Mercury's highly elliptical orbit makes the Sun appear noticeably larger at perihelion than at aphelion.

Mercury's Orbit & Rotation  shows the planet's 3 to 2 spin-orbit resonance.  It also compares Mercury's orbit and spin characteristics to Earth's.

Planet Mass Comparison


SKYMARVELS™
VIDEOS FEATURING MERCURY

The Solar System Barycenter

Inferior Planet Phases

Stunning Fields of View 002

Have You Ever . . . ?

"celestia4all" Site Preview