planet watch
above the solar system
Volume 23 -- Issue 5
Above the Solar System -- May 2017

Name May 01 May 11 May 21
Mercury 242o 11' 269o 46' 299o 05'
Venus 243o 39' 259o 32' 275o 22'
Earth 220o 49' 230o 30' 240o 08'
Mars 083o 00' 087o 59' 092o 54'
Ceres 069o 39' 071o 56' 073o 73'
Jupiter 199o 59' 200o 45' 201o 30'
Saturn 263o 08' 263o 26' 263o 44'
Plot planet positions using polar graph paper that you can download from this web site - or at that web site create your own.

This uses a coordinate system called heliocentric longitude where the 0o point is at the May or Vernal Equinox coordinate of 0 hours Right Ascension. From 0o longitude an object's orbit around the Sun and its heliocentric longitude increase at a rate determined by the orbital speed of the particular planet. The planet motion is counterclockwise as the animation below shows. Using the coordinates provided here a planet position may be plotted using degrees ranging from (0o to 360o) of heliocentric longitude. Once plotted the orbital position of one planet could be compared with that of another planet. Or the relative orbital speeds of an inner planet could be compared with that of an outer planet.

Terrestrial Planets and Dwarf Planet Ceres in Motion at 5 day intervals.
Above the Terrestrial Planets - May 2017

Click here to see an animated graphic showing the
Terrestrial Planets orbiting the Sun during 2017.

Explore our Solar System with this really cool tool. Click here to go to the Solar System Scope web site.