John Bridges: Mars Science Laboratory Blog
In addition to the blog, you can find some amazing videos and other content related to the mission, at:
We are having a set of drive-only sols, to reach our next Waypont Kimberley in the next few days. At Kimberley we may do our third drill hole. The plan is for material from the drill hole wto be analysed by X-ray diffraction in CheMin. However, in order to check that we havent left material over from our previous analyses at Cumberland, John Klein (Yellowknife Bay) or the Rocknest scooped soil, we have taken images of the CheMin sieve inlet with MAHLI. This MAHLI image was illuminated with the white LEDs around MAHLI.
This striking image is a mosaic of navigation camera images, at Junda outcrop with Mt. Sharp in the background. Junda is a place in W. Australia, which is where we are taking our locality names from in this part of our traverse.
We are setting some records for driving distance, having recently done 100 m in one sol. At our next 'waypoint' stop at Kimberley which we will reach in the next few days, we aim to do some detailed contact science.
We have succesfully passed through Dingo Gap, and this NavCam image shows the rearward view, where we have driven over the dune.
Its is also a great view of the the Multi Mission Radio Isotope Thermal Generator (RTG) with its cooling fins on Curiosity. When designing Curiosity, the Engineers decided that an RTG would provide more consistent power than solar panels and would therefore allow the rover to drive faster, further and do more scientific measurements. Our RTG is powered by the decay of Plutonium-238.
Since about the 1960s, energy from nuclear decay has been used to power spacecraft. RTGs use the thermal energy generated from alpha decay to generate a temperature difference across hundreds of thermocouples. As most of the power is dissipated as heat it allows us to maintain Curiosity at a working temperature, in addition to providing about 100 W electrical power.
Thermoelectric conversion has a relatively low efficiency, but requires no moving parts, which is a major advantage for Curiosity because we have to operate for many years without maintenance. Most of the NASA RTGs that have been flown on missions have hugely exceeded their original design life. Probably the most impressive examples are the Voyager probes, whose RTGs are still producing enough power (at the time of writing) for them to return valuable scientific data over 35 years after they were launched! They are the most distant man-made vehicles.
One of the other things you can see on this image is the 'billy can' in the top left, that covers the UHF transmiter. One of the few signs of damage on landing was the slight dent on this outer casing.
As we approach a full martian year (669 sols) we have travelled about 5 km. There is fine tuning to be done on the route to get us relatively quickly to the clay and iron oxide concentrations in Mt. Sharp, but try and minimise wear on the wheels.
The Opportunity Rover has travelled over 35 km since its landing in January 2004, so we have some way to go before we catch up with that record. The nominal mission for MSL is about 1 martian year, but just as MER Opportunity's was 90 sols, we hope to go on making discoveries for a lot longer than that.