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Planet Plotting

Once you have the planet ephemeris--the series of coordinates for the planet--you can plot the path of the planet on one these star maps:

* Each star map is for the evening around 9-10 pm,
but also shows the sky at other times in other seasons. Use this Table of Star Map Time Conversions.

The first thing you'll need to determine is whether or not the planet you picked is visible when the sky is dark on the dates you picked! If you find that the planet can only be plotted on star maps which do NOT match the dates you selected, that means that the planet is up only in the daytime--you can't see it!

If that happens, go back the the ephemeris generator and try a different planet or extend the span of dates for the ephemeris until you get several days which can be plotted.  You can also try checking the boxes on the Ephemeris Generator page labeled, "Suppress output during daylight,"  and, "Suppress output when body below horizon." This will give you no results if the planet is only above the horizon when it is daytime at your observing location.

GO Find That Planet!

Once you have plotted your planet's location over several days or weeks, you are ready to take the star map and go search in the real sky. You man need several days depending on the weather and clouds, before you can spot your planet. 

Go to an open outdoor location (take an adult for safety and transportation!), and  wait a few minutes to let your eyes adjust to the dark.  Hold the map with the direction you are facing at the bottom, so the "horizon" on the map matches the horizon in front of you. A compass can be helpful, and you should eventually be able to spot some of the constellations indicated on the map to get your orientation.  

Happy planet-hunting!!!

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