On 31st May 2016 Planet Mars will be closest it can get to Earth. In other words Planet Mars in its journey around Sun will reach a point in its orbit which is closest it can get at 3.06 a.m. on 31st May 2016 (30th May for most of western countries at 21.36 UTC).
Why Mars is Closest every 26 months? This closest approach is due to once in 26 months Celestial event “Mars Opposition to Sun” which occurred on 22 May 2016. Due to opposition Planet Mars, Earth and Sun were Opposite to Each other in a straight line from our perspective on earth. Whenever a planet is at Opposition planet in question would be closest in its orbit to earth than any other time. Hence it will appear brightest, biggest (from Telescope). Click here to see our article dated 22 May 2016 on "Mars Opposition to Sun".
Closest in Last 11 Years: As on 31st May 2016 at 3.06 a.m. Planet Mars is placed at 0.50321 AU = 75.28 million km from Earth. Generally the Minimum Distance from Mars to Earth is 55.7 Million km whereas Max. Distance Planet Mars can be away from Earth is 401.3 Million Km. If one can see last 11 years data of Mars Closest Distance to Earth presently Mars is Closest.
Time/Direction - Naked Eye: General Public can spot the Mars for many weeks easily with naked eye after sunset. In the evening Half hour after Sunset looking towards the sky opposite direction to sunset, one can spot Planet mars between East and North East direction. Whereas at midnight one can see it above his head while in the morning it can be spotted in West and North West Direction.
How it will appear:. It will appear like Orangish Red Non-Twinkling Bright object in the sky when seen by naked eye.
Importance of Mars Opposition/Closest Approach to Science – ISRO/NASA Mars Missions: once in every 26 months when earth and mars close to earth they provide excellent opportunity to launch mission and reach in shorter distance. ISRO Mars Orbiter Mission was launched on 5 November 2013 keeping in view the Mars Opposition event of year 2014. Taking benefit of Mars Opposition event of 2016 European Space Agency in association with Russian Federal Space Agency (Roscosmos) sent “ExoMars” first of its two spacecrafts in 2016.