The Sky This Week, 2010 July 27 – August 3 — Naval Oceanography Portal

As you wait for the sky to darken in the hours after sunset, keep an eye on the southwestern sky, where three planets are participating in one of the best series of conjunctions for the year.  The objects in question are Venus, Mars, and Saturn, and they will spend the next couple of weeks playing a celestial version of “leapfrog” during the twilight hours.  As the week opens, both Venus and Mars lie to the west of Saturn.  By the end of July Mars overtakes and passes the more distant ringed planet, with closest approach between the duo falling on the evening of the 31st.  In the meantime, dazzling Venus is chasing down both objects, and by the end of the week you’ll see an attractive triangle in the southwest with Mars and Venus forming the base and Saturn the apex.  Looking ahead to August, Venus blows by Saturn on the 7th, then passes Mars on the 18th.   

All of this activity in the early evening sky sets the stage for the entrance of Jupiter, who rises just as Saturn and his companions set.  By the end of the week you should see Old Jove in the east at around 11:00 pm, and by midnight he should be high enough to train the telescope in his direction.  Jupiter will become an easier target as August passes, rising about four minutes earlier each night.  He’s still missing his prominent South Equatorial Belt of dark clouds, but this in turn helps to accentuate the famous Great Red Spot, which is the planet’s most famous feature.

The Sky This Week, 2010 July 27 – August 3 — Naval Oceanography Portal