Courtesy of EarthSky
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Today, the planet Mars comes closest to Earth for all of this year.
Mars is at its best about every two Earth years, and now is the time. In fact, this planet is now shining at its brilliant best for several years to come. Tonight’s close encounter between the Earth and Mars will be the closest until the year 2014.
Because it’s close, Mars is also particularly bright in Earth’s sky right now. It’s happening because – in another two days – our planet Earth will pass in between the sun and Mars. Earth orbits the sun closer to Earth than Mars does, and we move in orbit more swiftly than Mars. Our world laps Mars on the average every 780 Earth days – about every two years. Astronomers call this an opposition of Mars. When it happens, Mars appears at its best in our sky.
Or almost its best. Although Mars is now brighter and closer than it’s been for two years – and brighter and closer than it will be again until 2014 – it’s not as bright and close as it can sometimes be. That cycle – the cycle of Mars very best appearances in our sky – comes once every 15 to 17 years. Mars will have one of those amazing years about 8 years from now.
Earth swings between Mars and the sun every other year, although at progressively later dates. Earth will next lap Mars in March 2012. After that, Earth will lap Mars in April 2014.
This isn’t the best possible opposition of Mars, but it’s still a grand time to see the red planet. Mars is out all night long now. It looks like a bright reddish star, although it shines with a steadier light than the twinkling stars. Look for Mars in the eastern sky at nightfall – highest in the sky around midnight – and in the west as morning dawn starts to light the sky.
By the way, the planet directly about-face of Mars at nightfall is the even brighter planet Jupiter. But Jupiter sets at early evening, while Mars shines all night long!
Written by Bruce McClurePrint This Post