Introduction:

The SPACE PHOENIX was an effort to acquire and fly discarded External Tanks using the model of the Land Grant University system. A consortium of 57 universities via the University Consortium for Atmospheric Research Foundation (UCAR), located in Boulder, CO chartered the External Tanks Corporation in the late 1980s as a vehicle to sell tank related services and platforms.

The following text was taken from the 1987 Symposium on Scientific Uses of Orbiting External Shuttle External Tanks, August 3-4, 1987 in Boulder. It summarizes the SPACE PHOENIX.

With permission of Tom Rogers, The following SPACE PHOENIX, UCAR and ETCO publications are made available for review: Adobe PDFs of the actual document are also available (requires Acrobat Reader 3.0 or higher):

Space Phoenix Overview:

A. Background

Early in its climb to orbit the Shuttle separates from the solid rocket boosters which then fall back to earth and are recovered for re-use. The external tank (ET) continues to supply liquid oxygen and liquid hydrogen to the Shuttle main engine until the ET and Orbiter have reached an altitude of approximately 160 km, attaining 98 to 99 percent of orbital velocity. At that point the ET is released from the Orbiter and its trajectory takes it back into the atmosphere where air friction heats it to the point of burn-up and disintegration.

A question asked by many associated with the U.S. civil space program is whether an ET could continue into orbit and accomplish other objectives there, thus making additional use of the $30 million ET and avoiding the several hundred million dollar cost of placing an equivalent mass in orbit.(l)

A number of studies have addressed this issue, each searching to discover useful and feasible ways to take advantage of ETs in orbit. For example, NASA’s Marshall Space Flight Center published the results of one such study in 1976(2), and Dr. Gerard K. O’Neill of Princeton University has also noted the opportunities presented by ETs.(3) Private organizations such as the Sophron Foundation have suggested how ETs could be transformed into “spartan”, low earth orbit (LEO) facilities.(4) These initial studies as well as others have led to an increased interest in utilization of ETs in space.(5)

The idea has also attracted attention in the Federal Government. In 1982, NASA sponsored a workshop at the California Space Institute of the University of California at San Diego on the use of Shuttle ETs. The participants of the workshop concluded that ‘… an ET should be put in space at the first reasonable opportunity.”(6) Later, the 1984 Office of Technology Assessment (OTA) report on Civilian Space Stations and the U.S. Future in Space noted several in-orbit uses for ETs.(7)

B. Recent Developments and Space Phoenix

In the past five years there have been a number of detailed engineering and cost studies on the opportunities and problems associated with the use of ETs in orbit. One of the most recent is a 1986 study by the Martin Marietta Aerospace Corporation, funded by the NASA-Marshall Space Flight Center. The study focused on the engineering and scientific considerations involved converting an ET into an orbiting Gamma-Ray Imaging Telescope.(8) The study was stimulated by an earlier NASA-sponsored report by the Smithsonian Astrophysical Observatory and another report conducted independently by Martin Marietta.(9)

Utilization of the ET was also noted in a report by the National Commission on Space:

” there is a potentially valuable artificial space resource that is now going to waste: the Shuttle’s external tanks. At present, with each successful flight of a Shuttle, an empty tank with mass greater than the full payload of the Shuttle itself, is brought. to 99 percent of orbital speed and then discarded to burn up in the atmosphere. The Shuttle fleet’s flight schedule suggests that over a l0-year period about 10,000 tons of tankage will be brought almost to orbit and then discarded. At standard Shuttle rates, it would cost about $35 billion to lift that mass to orbit…. there are reasonable arguments, involving potential hazards and the cost of maintaining tanks in orbit over time, against saving this resource, but we feel that so great a resource cannot be ignored, and propose that a new look be taken.(10)

At the Congressional level, the House Committee on Science and Technology emphasized the potential for ET use in a section of its report which accompanied the NASA Authorization Act of 1987 under the heading “External Tanks as Space Assets”:

The Committee believes that the Space Shuttle External Tank (ET) is a potentially valuable resource that should be considered for space development…. The Committee believes that NASA and the academic community should be encouraged to further study ET utilization and, in particular, the concept that qualified academic research groups might be awarded ET resources for space-based research much like the land-grant concept of the past. Universities, working cooperatively with industry, might dramatically increase scientific research opportunities, expand our Nation’s space infrastructure and broaden the spectrum of private space enterprise if such usage of the ET is found to be feasible, cost-effective and safe.(11)

In parallel with efforts mentioned above, the University Corporation for Atmospheric Research (UCAR) began in 1984 to study possible applications of ET resources for scientific research. UCAR’s growing focus on space-related experimental research and its experience in operating facilities to serve the atmospheric sciences community led it naturally to explore avenues for providing a management mechanism that could allow “universities, working cooperatively with industry”, to exploit the ETs. The program, called “Space Phoenix”, suggests an image of ETs “rising” from the charred remains that until now marked the end of their journey to space.

In 1985 the UCAR Space Phoenix Task Force was created to explore the potential scientific and commercial value of ETs. Subsequently, along with other science initiatives of potential benefit to the University community, the UCAR Foundation has developed the Space Phoenix program, and is now working to obtain title to orbiting ETs in the form of a fiscally neutral “space grant” from the U.S. government.(l2) The Space Phoenix program, as envisioned, is analogous to earlier “land-grant” programs and could serve to alleviate the substantial backlog of demand for scientific research facilities in near-Earth orbit while also opening up space for a larger number and variety of civil space activities.

By 1986 the Space Phoenix planning effort had advanced considerably, with emphasis moving from conceptualization to organization, capital formation, and program management. A first act in 1985 was to create the for-profit External Tanks Corporation (ETCO) as a Delaware corporation with offices in Boulder, Colorado. ETCO, owned 80% by the UCAR Foundation, will obtain private financing(l3) and manage commercial development of ET resources.

In November 1986, NASA created a special high-level committee chaired by the General Manager of NASA to work with UCAR on the Space Phoenix program. Soon after, UCAR and NASA officials began to draft a preliminary Memorandum of Understanding (MOU) regarding the transfer of title to orbiting ETs from NASA to UCAR, and other matters related to the use of ETs in space. The full text of this preliminary MOU, which was signed by UCAR during the Symposium, appears in Appendix B.

C. ETS – A Perishable Commodity

Only the United States has anything like the ET at present, but this will not always be the case. In fact, the USSR may have something similar very soon, and other nations may follow later. The U.S. should act now, through the Space Phoenix program, to develop its ET assets while it still enjoys a leadership position. This point was stressed in a presentation by George W. Morgenthaler, using his perspective as a former V.P. for Martin Marietta and Manager of the Skylab and Viking programs. Dr. Morgenthaler also described his concept for the use of an ET as a space port for the Japanese Mini-Shuttle.(l4)

D. Summary

The 1987 Symposium “Scientific Uses of Orbiting Shuttle External Tanks” provided space scientists from various disciplines the opportunity to exchange ideas on potential scientific experiments that would utilize ETs. Though not intended to be comprehensive in a detailed engineering sense, the Symposium was an initial and important step in defining the range of scientific opportunities presented by the use of ET facilities.

In the area of astronomy and astrophysics, the GRIT remains the most favorable near-term experimental option. However, the large length and volume of the ET make it an attractive candidate as a space-based “mountain top” observatory and, to a certain extent, on-going GRIT studies have served to “drive” more detailed studies of alternative astronomy experiments that might utilize an ET facility.

Life sciences experiments could take advantage of the large pressurized volume of an ET facility in several ways. The prospect of using an ET facility as a “greenhouse” or as a

storage and processing site for solid waste should be explored. Also, the utilization of an ET facility for large life science experimentation, such as housing for large colonies of organisms that could not be easily accommodated on Space Station, should be explored.

Research in materials science could also benefit from its conduct in an ET facility primarily in respect to lowering microgravity levels below 10(-6) or l0(-7) g. Also, the use of an ET as a materials storage facility is attractive. Tethering ET facilities together to create artificial gravity also emerged as a promising use.

Utilization of ET facilities for remote sensing focused on their very large surface mount possibilities. Larger antenna sizes and/or larger arrays could greatly enhance the surface resolution of observations.

An unexpected, but in retrospect obvious, focus of interest at the Symposium developed toward the near-term use of the unpressurized 5,000 cu ft intertank volume as housing for experiments. It was widely recommended that such use of the ET intertank volume be accomplished as soon as possible, both to relieve experimental backlogs and to serve as a stepping stone to more complete use of ETs for scientific research. Experiments planned for launch on balloons, sounding rockets, or in unpressurized lockers in the Shuttle cargo bay are likely candidates.

For More Information on the August 3-4, 1987 Symposium, download the following PDF. It gives a list of attendees, and a detailed overview of David Koch’s External Tank Gamma Ray Imaging Telescope (ET-GRIT):
August 1987 Symposium.pdf

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