The Landsat Data Continuity Mission ( LDCM or Landsat 8) represents the NASA and USGS joint effort to replacing the aging and semi-functional Landsat 7 satellite. The two organizations have been working for well over a decade on this problem and it looks like we will be well into a second before a solution is finally launched. The new instrument will differ from Landsat 7 in several ways, and more importantly will not in another key area. According to NASA:
"The centerpiece of the LDCM space segment is the OLI [Operational Land Imager]. By collecting land-surface data with spatial resolution and spectral band specifications consistent with historical Landsat data, the OLI instrument will advance future measurement capabilities. The OLI will feature two additional spectral channels: a "ultra-blue" band for coastal and aerosol studies, and a band for cirrus cloud detection. A thermal infrared sensor (TIRS) will collect data in two long wavelength bands that will be co-registered with OLI data."
In addition to the two extra multispectral bands, data will be quantized into 12 levels per channel rather than the 8 levels Landsat 7 quantization. The replacement of the broken Landsat 7 instrument is welcome, but NASA and the USGS as usual failed to address the greatest opportunity for improving Landsat usefulness: increased resolution. NASA and the USGS are continuing a lamentable tradition of a lack of vision with respect to earth imaging and a failure to acknowledge their user community. The main problem with Landsat, put quite simply, inadequate spatial resolution.
Is this in fact true? Consider the woefully sparse Landsat user community. A report published this year (2011) by the USGS entitled The Users, Uses, and Value of Landsat and Other Moderate-Resolution Satellite Imagery in the United States-Executive Report tried to determine exactly who was using Landsat and what they were using it for. The report concludes:
"...the survey revealed that respondents from multiple sectors use Landsat imagery in many different ways, as demonstrated by the breadth of project locations and scales, as well as application areas."
Really. I would state it more simply: essentially no one is using the data and the program as currently structured represents a tremendously inefficient use of taxpayer money. The USGS was only able to locate around 5000 Landsat users (around 2500 actually responded). Only 18 percent of the user community was from the private sector, the balance being academic and government agency users. Compare that to over 350,000 Goggle Earth downloads per month, comprised of mainly private sector users from all over the globe. Why should Goggle Earth enjoy more downloads in one day than the total number of Landsat users combined? Could the fact that Goggle Earth offers on-demand, high-resolution color imagery from state-of-the-art remote sensing platforms have something to do with it?
It may be unrealistic and impractical to expect Landsat to offer resolution competitive with the latest commercial satellite platforms as these interests probably enjoy political power disproportional to the size of their industry. But why, after over a decade of dithering couldn't NASA and the USGS figure out a way to increase the resolution of the Landsat panchromatic band to at least 10m? This would at least allow pan sharpening of the multispectral bands to something approaching usefulness. Although 10m resolution is nothing to marvel at, this one advancement, coupled with free distribution of the data and temporal relevance could probably increase Landsat usage ten fold. Isn't this the point of expending valuable taxpayer dollars: to benefit the maximum number of citizens?
NASA should consider upgrading the panchromatic sensor to 10m per pixel resolution immediately. It already has the technology as that is what is currently flying on the Earth Observer-1 ALI platform. It is ironic that the justification for the experimental EO-1 satellite was to pioneer advanced sensor technologies for the LDCM.
If you believe as I do, you might try contacting Senator Jay Rockefeller, Chairman of the US Senate Committee on Commerce, Science and Transportation at and express your views.