Human Journey

Candidate Debates: Where to Land the Mars Science Lab

This summer’s successful touchdown of, and subsequent science results from, the Phoenix Mars Lander have been setting the stage for NASA’s next big payload bound for the red planet: the Mars Science Laboratory (MSL), due to launch next fall.


An artist’s rendition of the MSL

—Image courtesy NASA/JPL-Caltech

Even as I type, planetary researchers are gathered in Monrovia, California, to argue the scientific merits of seven proposed landing sites for the upcoming mission.

Figuring out where to position the craft might not seem like that big a deal, since the science lab is actually a rover—the biggest NASA has ever tried to land on Mars—that’s designed for long-range mobility.

Unlike its famously long-lived but distance-challenged predecessors, the rovers Spirit and Opportunity, MSL will have the potential to travel up to 12 miles (19.3 kilometers) from its initial landing site.

But on a world more than 4,000 miles (kilometers) wide, location really will be key to the mission’s ultimate goal of figuring out whether the red planet could ever have supported life.

Maybe that’s why the conversation, notes Emily Lakdawalla on the Planetary Society’s blog, is unusual for a scientific meeting, in that this is no parade of slide show presentations punctuated by a blandly respectful Q&A.

Instead, teams of advocates for a particular site argue its merits based on their own research and open their studies up for up to an hour of discussion. The other Mars-ophiles in the room then “generally [beat] the stuffing out of the hard work that each research group has done,” Lakdawalla writes.

I wilt with envy of everyone who gets to be at this meeting, as I can only imagine the joy of watching science unfold like a political debate. Will evidence for the transient nature of its water be Nili Fossae’s undoing? Or will inverted channels send Miyamoto packing? News at eleven!


Exposed crater wall in Mawrth Vallis, one of the proposed MSL landing sites

—Image courtesy NASA/JPL/University of Arizona

Well, actually, I’m told that any news about a whittling down of the candidate sites won’t come until late October or early November, and even that’s just a guestimate. In the meantime, the Mars community will likely keep up the spirited discussion. Got a favorite site? Post below and tell us which, and why. Here’s the lucky seven, so far:

  • Eberswalde Crater
  • Gale Crater
  • Holden Crater
  • Mawrth Vallis
  • Miyamoto
  • Nili Fossae Trough
  • South Meridiani

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