Monday 15th October Sol 69

As we are currently static in Rocknest the use of the Mast instruments comes to the fore.  In particular, ChemCam is important.  ChemCam uses a laser to hit rocks at a distance of metres away.  This energy input creates a plasma above the laser spot.  The light from this plasma is viewed with a spectrometer and the peaks on the spectra compared to that known for different elements.  The laser we use has a wavelength of 1067 nm, which belongs to the near-infrared region of wavelengths.  Using only 3 Watt of power, our laser creates 30 mJ laser power per pulse, and it shoots at a rate of 15 Hz.  Near-infrared lasers are very common in terrestrial application like metal manufacturing and medical applications.  In analytical sciences in terrestrial labs, lasers are used to vaporize rocks and introduce elements of interest into a mass spectrometer.  Commercial lasers for that purpose have an energy output in the range of 120 mJ/ns in the near infrared and operate at a rate of up to 20 Hz.  Using ChemCam we can quickly compare spectra from different rocks to see if they have a similar composition.

The image shows the space shuttle Endeavour arriving today at its final destination in a hangar outside the California Science Center.  Just like MSL has shown for robotic exploration, Endeavour continues to show the enormous public interest in the human exploration of space.