Going, Going, Gone
The waning moon reaches last-quarter on Saturday, rising around 2:30am and shining high in the south as the sun rises at 7am. If you’re up before this time, look to the east for blazing Venus.
At magnitude –4, Venus is by far the brightest star-like object in our sky. So low in the sky, Venus puts on quite a display, dancing and shimmering above the horizon. While Venus is always bright, no matter its position in the sky. But when it is so close to the horizon, its light must pass through far more of earth’s atmosphere than if it were directly overhead, refracting and distorting that light before it reaches our eyes.
Over the coming weeks, this morning star’s dance reaches a feverish pitch, as Venus edges ever closer to the horizon. But our viewing window shrinks at the same time, as the sun rises to greet it more than 10 minutes earlier each week, with Venus leaving our pre-dawn skies by this time next month.
With vernal equinox now behind us and summer solstice still off in the distance, the sun sets a minute later each day. Tight on the sun’s heels this week is Jupiter, offering us a last glimpse very low in the west in early twilight. Looking for its golden hue, you might easily mistake Jupiter for Mercury, which is not as bright but shines a few degrees higher in the west. This is Mercury’s best evening apparition of the year, but it, too, is losing ground, disappearing from view over the next 10 days.
One stalwart shines through the night. Saturn, the dimmest of the visible planets, rises around 8pm and is high in the south by 2am. These hours after midnight are the best times for telescope viewers to spy on Saturn’s rings, which are beginning to open up after facing us head-on for the past couple years. And as the sky begins to lighten with the approach of dawn, Saturn shines above the west horizon.