Mars Mapper 2018 Opposition
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The map shows Mars with south up and east to the right, matching the inverted view of a Newtonian, or a refractor/catadioptric without a star diagonal.

Mars data for telescopic observers
Magnitude:      Phase: Angular diameter (arcsec):
Distance from Earth: Martian central-meridian longitude:
2018 opposition: Closest approach of 2018:

How to use Mars Mapper
The program always opens with the current Martian aspect presented to Earth. You can step forward or backward in time (useful to check recent images or sketches of Mars) in increments of one hour or an Earth day (a Martian day is 24 hours and 37 minutes long), or click the 'Reset to now' button to return to the present. If you wish to display Mars for a specific date (y/m/d format) and time, simply enter the desired values and click the 'Recalculate' button to accept them. Note: Mars Mapper uses 24-hour format Universal Time (UT), so UK-based observers should deduct one hour from British Summer Time while it is in force. To preserve accuracy, you may only enter dates and times between 1 May and 31 October 2018.