Langley Scientists To Propose Hosted Payload for EV-2 Mission
WASHINGTON — Atmospheric scientists at NASA’s Langley Research Center in Hampton, Va., want to fly a pollution-monitoring sensor on a still-to-be-determined commercial communications satellite bound for geostationary orbit around 2017.
If the Langley scientists find a willing partner with a suitable communications satellite in the pipeline, the team plans to submit a formal proposal this summer for the $150 million NASA expects to award in 2012 under its Earth Venture program of science-driven, low-cost missions.
Also, visit hostedpayload.com for more information on hosted payloads, presented by and Space News.
The Langley team’s proposal for the Earth Venture (EV)-2 mission opportunity aims to accomplish some of the science objectives of the Geostationary Coastal and Air Pollution Events (GEO-CAPE) mission that — like the Earth Venture program itself — was recommended by the National Research Council in 2007, Doreen Neil, a Langley scientist leading the EV-2 proposal effort, said in a May 3 interview.
One of the 15 missions the National Research Council’s first Earth science decadal survey urged NASA to undertake by 2020, GEO-CAPE was envisioned as a three-instrument geostationary satellite that could launch around 2016 for roughly $550 million. But an assessment NASA conducted last summer estimated such a mission would cost more than $1 billion, said Jay Al-Saadi, the NASA Earth Science Division’s GEO-CAPE project scientist at the agency’s headquarters here.
Al-Saadi is leading an effort to study cheaper options for achieving the GEO-CAPE science, and his recommendation is due to NASA leadership next year. Preliminary findings indicate hosting all three GEO-CAPE instruments on commercial satellites in geostationary orbits could cost about 30 percent less than building and launching a stand-alone satellite, Al-Saadi said in a May 12 interview. But more work must be done to refine those cost estimates and the technical approach, he said.
“The first pass through suggests that we might be able to save up to 30 percent or so over the cost of a dedicated launch,” Al-Saadi said. “But those cost estimates have a lot of uncertainty right now. We need to better understand those uncertainties and better work though the technical details, including pointing.”
Al-Saadi was referring to the pointing accuracy of the GEO-CAPE instruments, which would have to be much more precise than similar instruments flying in low Earth orbit. It appears many but not all types of commercial satellite platforms would be suitable hosts for these instruments, he said. Likewise, NASA potentially could fly the instruments on future Geostationary Operational Environmental Satellites (GOES) or the agency’s own Tracking and Data Relay Satellites (TDRS). But with the launch of the next satellites in those series fast approaching — TDRS-K is due to launch next year and GOES-R is on track for a 2015 launch — the Langley EV-2 mission concept looks like the first good opportunity to obtain GEO-CAPE data, Al-Saadi said.
NASA inaugurated the Earth Venture program in 2010 with the selection of five airborne science campaigns that will be conducted over five years aboard a variety of manned and unmanned aircraft.
A draft solicitation for EV-2, the Earth Venture program’s first orbital mission opportunity, was issued in February. A final solicitation is expected in the coming weeks. The winning team will be given up to $150 million to develop its mission in time for a 2017 launch.
The concept of hosting U.S. government payloads on commercial satellites is not new, but it has been done only a handful of times. Examples include Federal Aviation Administration payloads that are hosted on commercial satellites to provide pilots with corrected GPS information, and a commercial satellite that will launch this summer carrying an experimental Air Force missile warning payload.
In preparation for writing their EV-2 proposal, Langley scientists spent the past two years talking to government and industry officials who worked on previous hosted payload missions, Neil said. The benefits are clear, but the challenges are many, she said.
“The thing that’s great about hosted payloads is that you can get a mission on orbit in a relatively short amount of time, and if it’s cheap enough, after we do the first one, which we think it will be, we can train our next-generation project managers and systems engineers and principal investigators on real space hardware and the decision making that goes along with sending something off that’s the coordinated effort of hundreds of people,” Neil said.
One of the biggest hurdles is overcoming the cultural differences between the government and private industry, she said. Most NASA missions are not constrained by time, and spacecraft often take longer than anticipated to develop, whereas delays are less acceptable to commercial firms seeking to maximize profit on their investment in a satellite.
But NASA does know how to execute missions on time, as evidenced any time the agency plans for a planetary mission that must be ready to meet a definite launch window, Neil said.
“We manage to launch things to Mars every 26 months when the orbits line up,” she said. “So NASA knows how to do that, and it fits within the standard NASA formalities. We just have to adapt that to Earth science.”
The payload the Langley team would field is a new infrared imager designed to measure carbon monoxide levels in the troposphere, roughly the lowest 17 kilometers of the Earth’s atmosphere. For the past decade, carbon monoxide levels have been monitored by the Measurements of Pollution in the Troposphere (MOPITT) instrument flying on NASA’s Terra spacecraft in low Earth orbit.
Neil said spatial resolution of MOPITT imagery — at 480 square kilometers per pixel — is sufficient for the science the Langley team has in mind, but Terra’s four-day revisit time is far too long to study the complex chemical reactions that are taking place in the atmosphere driven by the sun. Observing carbon monoxide levels on a near-constant basis requires placing a sensor in geostationary orbit, which is one of the objectives of the GEO-CAPE mission concept, she said.
Langley on April 8 issued a solicitation for potential partners to host such a sensor. The center is looking for a host geostationary spacecraft that will be built in the United States and launched in 2017. It must be positioned between 85 degrees and 110 degrees west latitude — which would give it a view of North and South America — and be able to accommodate a payload of up to 100 kilograms requiring up to 200 watts of power. Terra’s MOPITT instrument was developed byInternational of Canada. Neil, however, would not reveal any of Langley’s potential partners for the EV-2 competition.
Neil said a commercial satellite operator willing to host the Langley pollution sensor — assuming NASA selects and funds the project — could receive progress payments prior to the satellites launch, a time during which the satellite would not otherwise be generating revenue. Additionally, a lump-sum payment received early in the life of the satellite could be more attractive than a similar amount of money spread over the typical 15-year lifespan of commercial comsats, she said.