Mars at Opposition – March 2012
Mars will reach opposition (when it is directly opposite the Sun in the sky and brightest for this apparition) on the night of March 3rd 2012, positioned 5º.4 SSW of the star Coxa ( Leo or Theta Leonis, mag. +3.9) and 4º.5 West of Leonis. Mars is now brighter and closer than it’s been for two years – and brighter and closer than it will be again until 2014.
However, Mars’ perigee (closest point to the Earth) will take place two days later – on March 5th – when it is 0.6737 AU (100.7 million kms or 62.6 million miles) from the Earth. This is due to the eccentricity of the orbit of Mars.
It’ll be hard to miss Mars because it’s the fourth-brightest star-like object to light up the night at this time, after the planets Venus and Jupiter, and the star Sirius.
You can find Mars in the eastern sky at nightfall and early evening, in front of the constellation Leo the Lion. Leo’s brightest star, Regulus, is to the upper right of Mars when they are in the east in the evening hours.
On opposition day this 2012, Mars will shine at magnitude -1.2 and will have an apparent disk diameter of 13″.9. This is not as bright nor as large (when seen through a telescope) as it was at its previous opposition in January 2010, when the planet reached magnitude -1.3 and had an apparent diameter of 14″.1.
Trivia: At opposition, the Earth passes in between the sun and Mars, so that the sun, Earth and Mars lie along a line in space. During this event a superior planet like Mars rises around sunset, is visible throughout the night and sets around sunrise. Its highest point in the sky is reached when it crosses the observer’s meridian at local midnight (due South at midnight in the Northern hemisphere and due North at midnight in the Southern hemisphere).
Say “Hello” to the Red Planet
Through the Beauty without Borders program, Astronomers Without Borders (AWB) will bring together groups around the world to enjoy the event through observing, webcasts, activities, photography and poetry.
Mars will come into Opposition on March 3, 2012 in the constellation Leo with its face fully illuminated by the Sun and two days later, on March 5, 2012, the planet will have its closest approach to Earth during this apparition: 100.78 million km (0.6737 AU)—the best time to say “Hello” to the Red Planet.
Join this event and share it with your friends!
# # #
- Nakedeyeplanets.com: Mars – Opposition Data
- SkyandTelescope.com – Resources: Mars Previewer (freeware)
- NASA’s Solar System Simulator v4 (generates Martian disk images for a particular date)
- Mars Ephemeris Generator 2.2
- Stellarium free planetarium software