RT @Astroguyz: Comet A1 Siding Spring versus Mars… Views in Time and Space: universetoday.com/115264/comet-a… Perspectives on this weekend’s big event.
RT @Astroguyz: Comet A1 Siding Spring versus Mars… Views in Time and Space: universetoday.com/115264/comet-a… Perspectives on this weekend’s big event.