Independent team urges polar orbiting gap filler satellite to prevent coverage loss
An independent review team chartered by the National Oceanic and Atmospheric Administration urges the agency to immediately start development of a gap filler satellite to head off the high probability of a gap in polar-orbiting satellite data.
Weather forecasters face a well-known problem of the first of two planned Joint Polar Satellite Program satellites in an afternoon orbit not being ready for service until well after the expected mission end of the Suomi National Polar-orbiting Partnership, a polar-orbiting satellite that itself is a gap-filler. The Government Accountability Office estimates the gap could span from 17 to 53 months, starting in late 2016.
"NOAA currently has a high quality weather forecasting capability that has become very much a part of the fabric of the U.S. society," says the team's Nov. 8 report (.pdf) released mid-month to the public. "It affects our safety, our quality of life and our economy." The team was chaired by Thomas Young, a former director of the NASA Goddard Space Flight Center.
NOAA has already concluded that the schedule of the first JPSS satellite can't be accelerated; the agency says it should launch in early 2017. A preliminary NOAA and NASA analysis also estimated that the time to implement a gap filler satellite would be five years, says the report--but nonetheless, it recommends development of an interim polar-orbiting weather satellite ideally "available to launch before S-NPP reaches the end of its mission life."
Satellite instruments are the component that would consume the most time, the report says. It recommends the interim satellite carry only two sensors, as opposed to the five instruments slated for JPSS-1: the Advanced Technology Microwave Sounds and the Cross-track Infrared Sounder. The JPSS program office has under review proposals for ATMS and CrlS proposals for the second JPSS satellite, the report notes, adding that NOAA should simply increase the number of instruments it intends to buy.
As for the spacecraft itself, the report says that "there are examples of small low earth orbit spacecraft being completed 2-3 years from start."
Given the right incentives and contract structures, a gap filler satellite could be ready before the end of 2017, the report says.
The team behind it is also critical of the JPSS program, calling it fragile in the face of potential mishaps that could include launch failure. Unlike the Polar Operational Environmental Satellites civil weather satellite program, which built satellites in blocks, the JPSS program is building just two satellites--JPSS-1 and JPSS-2.
That leaves the door open to a very long satellite gap, the report notes, should JPSS-1 fail to obtain its correct orbit, or should JPSS-2 not operate until the end of its mission life. The program should have sufficient satellites under development so that two failures, rather than one, are necessary to create a gap, it says.
"Decisions need to be made, resources dedicated and management actions implemented to quickly move the JPSS program in this direction," it urges.
JPSS right now is the only U.S. polar weather satellite in development; the Air Force in January 2012 canceled its Defense Weather Satellite System program, which would have sent up polar orbiters for the early morning orbit.
- download the report (.pdf)