Voyager, Pioneer, the Curiosity Rover, the Hubble Telescope and the New Horizons space craft all have one thing in common they were all conceived, built, and delivered to NASA by its contractors. But not all missions are alike in these ways, and not all proposed missions even make it to the drawing board. Lets take a look at the process of getting an idea into space.
I talked with Dr. Harold Reitsema, a member of the Shoreline Amateur Astronomical Association and semi-retired rocket scientist who worked on both the Kepler and New Horizons spacecraft. He explained that NASA does science missions in two very different ways.
The first is known as a Principal Investigator Led Mission in which a team of knowledgeable scientists is formed, then becomes aligned with a spacecraft builder, some NASA scientists and even sometimes a NASA center, and finally puts together a complete mission design. The design includes the satellite, its instruments, who the operator will be, and how the data that comes from the spacecraft is stored and analyzed. The team then writes a proposal that was solicited by NASA through what is known as an Announcement of Opportunity.
This Announcement of Opportunity defines a broad area of science, such as cosmology or the origin of the solar system, and anyone with an idea that fits that objective can respond with a proposal for a full mission. Proposals can therefore be quite diverse. For example, one might be for an orbiter to study the atmosphere of Jupiter while another proposes a lander on Venus. Both fall under the category of planetary exploration.
NASA then creates two panels, one that evaluates the value of the science and one that studies the risks associated with building the hardware to actually accomplish the missions goals. The scientists submitting the proposals then approach private industries such as Lockheed or Ball Aerospace to work out the design and construction details. Often industries try to work with proposals from several teams to increase the chances of being approved since each announcement of opportunity can be met with a dozen or more proposals. The Kepler telescope and the New Horizons spacecraft were both missions of this type that Dr. Reitsema worked on for Ball Aerospace. Clearly, those proposals were accepted.
Such missions are relatively low in cost and risk. Larger, more expensive endeavors, such as the Mars Rovers or the Hubble Telescope, take a different course from conception to completion. In these cases, NASA puts out a list of requirements that a mission must meet and requests proposals from the aerospace industry that meet these requirements. The James Webb Telescope is a prime example. NASA knew they wanted to do a really big infrared telescope and it needed to be able to aim with a high accuracy, have a particular sensitivity, size, and life expectancy, and operate at extremely low temperatures. NASA then puts out a "Request for Proposals" to accomplish their mission.
Such endeavors require vast resources so the number of proposals is limited and they almost always come from the aerospace industry. Since these missions have never been done before and often require untested or even nonexistent technologies, NASA is willing to cover certain cost overruns. Again, the Webb is a good example. Originally proposed at a cost of around $1.6 billion in 1997, it jumped to $5 billion by 2007 and now is estimated at almost $9 billion! Part of the problem was that it is very difficult to perform tests here on Earth to evaluate how it will behave in a weightless environment, with its optics near absolute zero and electronics at room temperature.
So, to summarize, missions are the result of two processes. In the first, groups propose different ideas in response to an announcement of opportunity from NASA to study a broad branch of science. In the second, proposals are submitted for specific investigations as defined by NASA. Each scenario brings us a better understanding of whats up in the sky.
This month in history:
Peter Burkey is a Holland resident. Contact him at pburkey@comcast.net.
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What's Up in the Sky? How NASA missions are born - HollandSentinel.com