Mercury and Mars dominate the evening sky this month, with Mercury putting on its best display of the year while Mars warms up for its best appearance in a decade. Earth is overtaking Mars in the race around the sun. Mars will appear to move to the east, or retrograde, against the stars, reaching the constellation of Sagittarius on May 11. Mars then resumes its normal, westerly course, ending the month in Scorpius. As the two planets draw closer together, Mars appears bigger and brighter. Mars also is slowly nearing the sun which increases the planet’s brightness.