MARS: CLOSEST APPROACH 2007

In December 2007, the Mars closest approach and opposition will occur within a week of each other. This is an exciting time for astronomers and planetary geologists to image and study our planetary neighbor. On December 18, Mars will be the closest it has been in the last two years, reaching a distance of 55 million miles from Earth. This series of images was taken with Hubble's Wide Field Planetary Camera 2 on December 1-7, within two weeks of its December 2007 closest approach. Each image shows the planet rotating about 90 degrees from the next image. This gives astronomers a full-globe look at the Red Planet.

Mars and Earth have a "close encounter" about every 26 months. These periodic encounters are due to the differences in the two planets' orbits. Earth goes around the Sun twice as fast as Mars, lapping the Red Planet about every two years. Both planets have elliptical orbits, so their close encounters are not always at the same distance. In its close encounter with Earth in 2003, for example, Mars was about 20 million miles closer than it is in the 2007 closest approach, resulting in a much larger image of Mars as viewed from Earth in 2003.

The planet appears free of any dust storms during this closest approach, however, there are significant clouds visible in both the northern and southern polar cap regions. The resolution is 13 miles (21 kilometers) per pixel.

Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), J. Bell (Cornell University), and M. Wolff (Space Science Institute, Boulder)