... Spiral galaxy M33 is a mid-sized member of our Local Group of Galaxies. ... Announcing Comet Machholz . ... Debris Disks Surround Distant Suns . ... But inset are actual images of such disks around two nearby stars - AU Microscopii (top left; edge-on) and HD107146 (right: face-on) - as seen by the Hubble Space Telescope. Jupiter and the Moon s Shadowed Horizon . ... What was that star? In the Center of the Heart Nebula . ... What powers the Heart Nebula? ... Filaments Across the Sun . ...