NASA is taking a risk that it may send one of its Mars rover vehicles to its death, but the high-stakes potential scientific payoff makes the gamble more than worthwhile.

That was the message from NASA briefers, speaking to the media last week. They said the tricky voyage may occur July 7 or 9.

The plucky Mars rover Opportunity, which much like its sister Spirit has functioned 12 times longer than the 90 days initially expected, has been racing across the red planet, and in recent times has been scouting ways to maneuver down into the immense Victoria Crater.

A way down seems to have been found at the crater rim, an area called Duck Bay. It seems to be a 100 meter slope down into the crater, a gradient that Opportunity can handle. The rover has tackled steeper inclines before. But there is a ripple in the surface of the slope, and Opportunity had problems with a different ripple area, up on the surface, where the rover had difficulty escaping it.

Also, there are “some unknowns,” according to Alan Stern, associate NASA administrator of the science directorate. “We can’t be certain about the terrain and the footing” that rover will encounter. Also, what if one of the six rover wheels loses power? It could be difficult or impossible to climb out of the crater.

But Stern rejected a journalist’s question as to whether this amounts to sending Opportunity on a suicide mission, saying there is enough likelihood of success. And the potential “rewards are worth the risks.” Stern said.

When the crater was formed by a meteor hit, huge amounts of Martian material were ejected from the crater, so that it has bed rock at the crater floor, and ejecta forming the crater rim. In between those two layers, there is a band of bright material that formed the surface of the planet before the crater was formed. And that bright rock may hold a goldmine of scientific information, briefers said. Opportunity can examine the bright band with its rock abrasion tool (RAT) as the rover traverses the downward slope to the crater floor.

Before the descent begins for real, Opportunity will head down the slope for just one vehicle length, stop, then back out onto level ground. NASA personnel will review the data before beginning the trip in earnest.

Glowing Ice Clouds

A NASA satellite has captured the first occurrence this summer of mysterious iridescent polar clouds that form 50 miles above Earth’s surface. The first observations of these clouds by the Aeronomy of Ice in the Mesosphere (AIM) satellite occurred above 70 degrees north May 25.

Observers on the ground began seeing the clouds June 6 over northern Europe. AIM is the first satellite mission dedicated to studying them.

TC4 To Begin

The Tropical Composition, Cloud and Climate Coupling (TC4) field campaign will begin this summer in San Jose, Costa Rica, with an investigation into how chemical compounds in the air are transported vertically into the stratosphere and how that transport affects cloud formation and climate, NASA announced.

The study will begin the week of July 16 with coordinated observations from satellites, high-flying NASA research aircraft, balloons and ground-based radar. Targets of these measurements are gases, aerosols and ice crystals that flow from the top of the strong storm systems that form over the warm tropical ocean.