Back Alley Astronomy

Figure 1. The Sun-like star WASP-47 hosts a transiting Hot Jupiter flanked by two low-mass planets, and all three have periods short...

Imaginary view of ancient Mars, ca. 4.4 billion years ago, with clouds and an ocean. Composite of NASA and NOAA images. ----------...

Figure 1. Artist’s impression of Earth during the Hadean aeon, when bombardment by asteroids and comets was frequent. Image credit: ...