... NGC 4755: A Jewel Box of Stars . ... Clearly, dark windblown sand surrounds outcropping of light sedimentary rock across the floor of crater Arabia Terra. ... On the night of August 12, from moonset until dawn was a good time to see meteors. Enthusiasts watched as comet dust rained on planet Earth, streaking through dark skies during the annual Perseid Meteor Shower. ... Clouds near the horizon can block sunlight from reflecting off air, making columns outward from the Sun appear unusually dark. ...