Agreed, the Mössbauer is important, but a rough half-life calculation indicates that five years after landing the integration time will have to increase by a factor of 105 to get the same number of counts. Since the background count rate will remain constant, an even longer integration time will be needed to get the same S/N ratio.

The early Mössbauer integrations were several hours so we're looking at integration times measured in weeks, which will seriously delay our travel. I imagine the Mössbauer will be used sparingly.

Steve M

Important Mössbauer integrations were allowed 24 hours even at the outset of the mission. See, e.g., Roving Mars at 114 (describing two 24 hour Mössbauer integrations on El Capitan in Eagle Crater). The latest Opportunity update suggests that the most recent integration occurred over 12 days, but doesn't specify if the instrument was in use continuously.

It would be interesting to hear if techniques exist for making effective use of shorter integrations with the instrument in its weakened state. Roving Mars speaks of "tuning" the instrument for different kinds of readings. I wonder if it's possible to tune the instrument to a "coarse" setting that would yield at least a modicum of useful information from a quantity of radiation flux (if that's the right term) which earlier would have been considered too small to bother with.

CosmicRocker pointed out several posts upthread how few of us had ever heard of a Mössbauer spectrometer prior to the Rover missions. Professor Mössbauer discovered the effect which bears his name in 1957 and is still with us (he turns 80 on January 31). It would be interesting to learn if he ever dreamed that Mössbauer spectroscopy would be used on Mars in his lifetime, and what he makes of the Rovers and their discoveries.

TTT

Here's the latest navcam mosaic, taken after the drive during sol 1776.

Have a look to the route map and you will see that we are next to a little crater which was already visible from the previous site.
I'm eager to see the rest of the navcam pictures.

Next stop? Or drive on past...?

A color mosaic perhaps and then go for good. My 2c.
Here's the crater in polar view.

I agree. It's a nice view, but I don't see any reason to linger here.

Ranger. Nice name.

Are those giant dunes that appear to be part of the horizon?

Funny how ecstatic we would have been if we had encountered this crater early in the mission. Now it is just, "yawn, drive on.."

Some may think that this is just another pothole on the Road to Endeavour, but I still think it's worthy of a photo



Astro0

EDIT: A larger version (with no text) is now on my blog.

Yeah. Eagle Crater's outcrops pale in comparison. But Eagle lives in history as the most astounding first look any lander has had to date. IMHO

We're moving again. What a relief! {/pun}

It would be great to get color images. The rocks look dark on the navcam compared to the pavement.

And it could easily have been the unluckiest landing spot in history. Imagine if Eagle had been a filled-in sand trap like so many craters encountered.

Speaking of filled in craters: Ranger looks like it must have a very deep layer of sand and dust in it, unless it was unusually shallow. Are the craters in this area old, or is the sand/dust just really prone to getting blown around? These craters look so much more filled in than things like Meteor Crater in Arizona. Are there estimates of their age?