Welcome to the University of Texas Skywatchers Report for Monday August 15th through Sunday August 21st.

The full moon for the month of August is on the morning of Thursday the 18th so we'll have a waxing gibbous moon for the first half of the week and a waning gibbous moon for the second half of the week. This full moon is known as the Grain Moon and the Green Corn Moon.

There is still a chance to see the five naked eye planets this week shortly after sunset if you have a good view of the western horizon.

Venus, Mercury, and Jupiter are all close together low in the west right after sunset. Venus and Jupiter are bright enough that you should be able to pick them out, even in twilight and they can help you spot the fainter Mercury. Mercury will be to the left of Venus and below Jupiter all week. All three planets will set around 9:10 to 9:30 p.m. this week. Mercury is at its greatest elongation from the sun on Tuesday the 16th.

Mars and Saturn are up in the south-southwest in the evening twilight near the orange star Antares in the constellation Scorpius. Mars is setting around 1 a.m. this week, followed by Saturn about 20 minutes later.

In space anniversaries this week, August 17th marks the 50th anniversary of the launch of the Pioneer 7 spacecraft into solar orbit as part of the Pioneer program's interplanetary space weather network. The Pioneer 6, 7, 8, and 9 missions made the first detailed measurements of the solar wind, the solar magnetic field, and cosmic rays and paved the way for further exploration of the solar system by the Pioneer 10 and 11 spacecraft that launched in the early 1970s. Pioneer 7 was last contacted in 1995 and the spacecraft and one of its science instruments were found to still be functioning.

Public viewing is finished for the summer session. Fall semester viewing will start in a couple of weeks. Please check back for details on starting dates and times.

Thank you for calling the University of Texas Skywatchers Report.

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