Two planets, a bright star and the moon gather in the southwestern sky this evening August 21. Look about 45 minutes to an hour after sunset to see it best. Created with Stellarium

You’re invited to the farewell party tonight. Mars, Saturn, Spica and the moon will gather in a big, beautiful bunch one last time this year. Be sure you have a spot with a clear view to the southwest. The moon will be easy to see and will help you find the others. I always like to take along binoculars to add depth and extra snap to scenes like this one. Start looking about 45 minutes to an hour after sundown.

On September 18, when the crescent moon returns for a replay, Spica and Saturn will be lost in the twilight glow with only Mars remaining. Earth’s revolution around the sun causes all the stars and (sooner or later) planets to be swallowed up by the western horizon. Mars is close enough to Earth that its rapid orbital motion to the east helps it avoid sinking away in the west as quickly as the outer planets. Mars’ zip won’t help stay apace forever; Earth is faster yet and the Red Planet will finally disappear from the evening sky by late fall. Parting is such sweet sorrow.

Venus (left), Jupiter (top), along with the V-shaped Hyades star cluster (right of Jupiter) and Orion (lower right) light up the eastern sky at dawn earlier this week. Photo: Bob King

We’re blessed with two twilights – one at dusk, the other at dawn. Whichever one you spend your time with, you won’t go wrong. One could argue the morning version is even more stunning than the evening. Not only are Venus and Jupiter high and bright, but Orion and his starry belt climb above the trees, adding even more luster to the scene. If it’s inner peace you’re seeking, I recommend a dawn outing. Before the world revs up for another day, the sense of quietude can be profound.

Two frames from NASA-TV showing cosmonaut Gennady Padalka (at left with large backpack) using a lacrosse-like device to launch the small spherical satellite, a 20-lb. steel ball into space below and behind the space station. Click to see a video.

Gennady Padalka  had some fun yesterday while he and fellow cosmonaut Yuri Malenchenko were out for a little 7-hour spacewalk at the International Space Station. Besides moving a crane to a new location and installing a shield to protect the ship from micrometeroid impacts, he got to launch a satellite all by himself. You’ve got to see the video to appreciate how easy it was to launch – one quick push and the shiny steel ball floated away. To avoid any chance of it hitting the ISS, he aimed it behind and below the station.

We may have come a long way from the atlatl, but the concept of release by throwing from an extension of the human arm is similar. Clever humans.

The Russians will monitor the shiny ball from the ground to work on techniques for tracking space debris and its re-entry into our atmosphere. The little satellite will orbit Earth for about 3 months. It should be visible in binoculars; when more information on its orbit becomes available, I’ll post viewing times.