The National Aeronautics and Space Administration (NASA) is currently reviewing and analyzing practical alternatives to an manned servicing mission to the Hubble Space Telescope (HST), including the use of tele-robotics. IEEE-USA supports exploring all possible avenues to prolong the useful life of the telescope for the benefit of science and humanity. The James Webb Space Telescope will provide more capability for scientific research, but will not launch until 2011, at the earliest. The absence of the Hubble’s extraordinary abilities will adversely impact astronomical research. Maintaining the Hubble will accommodate any delays in the Webb Space Telescope. And having both telescopes on the station until the Hubble concludes its mission will increase space research capacity.

IEEE-USA believes that NASA’s benefit and risk analyses should consider the future scientific value of maintaining the Hubble and that the public should be informed about the considerations and tradeoffs considered in making a final decision on a service mission to the HST. To this end, IEEE-USA recommends that:

• NASA should continue planning and preparing for the SM-4 servicing mission, while expert panels and the National Academy of Science develop their reports, and the issue is thoroughly reviewed.
   
• In consultation with other government agencies, external experts, and the National Research Council, NASA should review strive to develop procedures, technology and equipment that would allow the safe servicing of the HST, including the possible use of tele-operated robots to maintain the long-term viability of the HST.

This statement was developed by the IEEE-USA's Committee on Transportation and Aerospace Technology Policy and represents the considered judgment of a group of U.S. IEEE members with expertise in the subject field. IEEE-USA is an organizational unit of the IEEE. It was created in 1973 to advance the public good and promote the careers and public-policy interests of the more than 225,000 technology professionals who are U.S. members of the IEEE. The IEEE is the world's largest technical professional society. For more information, go to http://www.ieeeusa.org.

BACKGROUND

The Hubble Space Telescope (HST) is a 2.4-meter reflecting telescope, which was deployed in low-Earth orbit (600 kilometers) by the crew of the space shuttle Discovery on 25 April 1990. HST is a cooperative program of the European Space Agency and the National Aeronautics and Space Administration (NASA) to operate a long-lived space-based observatory for the benefit of the international astronomical community [1]. HST’s location above the Earth’s atmosphere allows its scientific instruments (cameras, spectrographs and other sensors) to acquire high-resolution images of astronomical objects. Since its launch, the Hubble telescope has provided astronomers and humanity with measurements that provided, among other results, fundamental new results in planetary science; discovery of the most distant object in the solar system; more accurate estimates of the age of the universe; better measurements of the universe’s rate of expansion; the deepest portrait of the visible universe ever achieved by humankind; the discovery of new stars and dynamic phenomena in space; and new views of comets and black holes [2, 3].
Since 1990, astronauts have serviced the Hubble Space Telescope (HST) approximately every three (3) years, replacing gyroscopes, electronic boxes and other limited-life items, and installing new science instruments. The HST requires these servicing missions to keep the telescope from spiraling too close to the Earth and re-entering the atmosphere, and to continue to be effective in collecting, processing and transmitting information [2].

On 16 January 2004, the NASA administrator announced the cancellation of Shuttle Service Mission 4 to the Hubble Space Telescope (HST), which would have performed maintenance work, replaced gyroscopes needed to sustain the telescopes orbit and installed new instruments. Administrator O'Keefe cited the new safety guidelines set out following the Columbia tragedy as the primary basis for his decision. Without this servicing mission, the Hubble telescope is unlikely to last until 2010 as planned.

In March 2004, the NASA administrator requested an assessment of serving options by the National Academies’ National Research Council. The NRC’s Committee on the Assessment of Options for Extending the Life of the Hubble Space Telescope provided its interim report on 13 July 2004 reinforcing the scientific merit of the HST and recommending that NASA “commit to a serving mission to the Hubble Space Telescope that accomplishes the objectives of the originally planned SM-4 mission, including both the replacement of the present instruments with the two instruments already developed for flight – the Wide Field Camera-3 and the Cosmic Origins Spectroscope – and the engineering objectives, such as gyroscope and battery replacements.” Recognizing the challenges and uncertainties associated with a proposed robotic servicing mission, the report also recommends that “NASA should take no actions that would preclude a space shuttle servicing mission to the Hubble Space Telescope.” [4]

In 1 June 2004 remarks to the American Astronomical Society, the NASA Administrator announced new plans to consider proposals for robotic servicing of the HST. Several requests for proposals were subsequently released by NASA’s Goddard Space Flight Center. A final decision to proceed with a robotic servicing mission, however, is contingent on the final report of the National Research Council, passage by Congress of necessary budget authority to support a Hubble repair mission, and clearance by the proposed robotic mission of a “critical design review”.

Notes:

[1] The Hubble Project, On-line: http://hubble.nasa.gov/. See also, Space Telescope Science Institute: Overview of the Hubble Space Telescope, On-line: http://www.stsci.edu/hst/HST_overview/.

[2] Space Telescope Science Institute: News Center, On-line: http://hubble.stsci.edu/newscenter

[3] John Noble Wilford: “Astronomers Discover Most Distant Object in Solar System,” The New York Times, 15 March 2004.

[4] Assessment of Options for Extending the Life of the Hubble Space Telescope, National Research Council, 13 July 2004. On-line: http://books.nap.edu/books/NI000551/html/index.html