Astronomy Picture of the Day

Explanation: Anticipating the celestial shadow play of a solar eclipse, sky gazers across Germany watched the Sun rise on May 31. In Bonn, astrophotographer Thilo Kranz had set up his small refractor telescope and camera on the Kennedy Bridge across the Rhein river to get a good view to the northeast. The timing of this eclipse must have seemed ideal for a local balloon flight too, as hot air balloonists also favour early morning hours with usually calm surface winds. Kranz and colleagues had noticed a balloon drifting in the hazy sky near the horizon and speculated about viewing the eclipse from on board. But when the eclipsed Sun finally emerged into view they were delighted to see the lighter-than-air craft make the occasion a very special show from their own vantage point. In fact, in the central panel of this montage of Kranz's telescopic eclipse images, the silhouetted balloon reminds the APOD editors of a remarkably well-fed exclamation mark!