No one knows exactly how Comet Siding Spring will look from the Red Planet when it blows by just 83,263 miles (134,000 km) from its surface. Certainly a whole lot brighter than we see it from Earth! The close shave will happen around 1:28 p.m. CDT this Sunday October 19th.
I spotted it last night at about magnitude +11 not far from Mars in a 15-inch (37-cm) telescope from northern Minnesota. The comet was a faint smudge, but then my eyes were 151 million miles from the duo. Distances like can suck the drama right out of a comet. Seen up close from Mars, it would drop the jaws of a entire crew of astronauts.
When nearest, Siding Spring is expected to shine at magnitude -5 or about twice as bright as Venus. Mind you, that estimate considers the entire comet crunched down into a dot. But for those who remember, Comet Hale-Bopp’s appearance in spring 1997, it shown at zero magnitude, 100 times fainter than Siding Spring, and made for one of the most impressive naked eye sights in years.
More recently, Comet McNaught climaxed at magnitude -5 in the daytime sky near the sun in January 2007. It was plainly visible in binoculars and telescopes in a blue sky if you knew exactly where to look and took care to avoid the sun. Martians will be far luckier as their comet will appear in a dark sky.
Comet C/2013 Siding Spring as it rises and sets over the Curiosity Rover this weekend October 18-19. Click the control to start, to pause and for other options. Credit: Solarsystemscope.com
To help you picture it the folks at Solarsystemscope.com, famed for their simulations of the dearly departed Comet ISON, have created another gem, a look at Comet Siding Spring as it wheels across the robotic gaze of the Curiosity Rover in the next few nights.
Seen from Mars, the comet bobs along Eridanus the River southwest of Orion, passing high in the southern sky overnight. What a sight! The comet nucleus is only about 0.4 miles (700 meters) across, but the coma or atmosphere fluffs out to around 12,000 miles (19,300 km). Seen from the ground, Siding Spring would span about 8°of sky or 16 full moons from head to tail. Moving at 1.5° per minute, it will be fast enough to see crawl across the heavens in real time with the naked eye. Ah, if only we could be there.
Rest assured we’ll get the latest images and results from the rovers and orbiting spacecraft posted here asap.
As usual, several outlets will be featuring live webcasts and special programs Sunday. Here are two:
An exciting weekend lies ahead!